Compounds for complexation of rare earth elements and/or s-, p-, d- block metals, their coordination compounds, peptide conjugates, method of their preparation and use thereof

Abstract

The present invention relates to compounds of general formula (I) for use as complexing agents. The invention further relates to the coordination compounds thereof, peptide conjugates, method of their preparation and use thereof.

Description

STATE OF ART

The present invention relates to new macrocyclic compounds suitable as cross-bridged chelators for complexation of rare earth elements and/or s-, p-, d-block metals, forming extremely stable coordination compounds. These coordination compounds are suitable for use as labels for quantitative detection of peptide conjugates, and/or as contrast agents for magnetic resonance imaging. The invention further relates to a method of preparation of the chelators and to a method of tracing peptide/protein containing medicaments.

BACKGROUND ART

Metal elements find biomedical applications such as imaging contrast agents, radiotherapeutic agents or bioanalytical labels. For most of these applications, it is necessary to bind the metal in a stable chelate that can be covalently linked to other molecules, such as targeting vectors based on peptides or antibodies. The most universal example of a chelator applicable to majority of metal elements is DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and its derivatives. A broad range of other chelators have been developed specifically for particular metal elements. [Price E. W., Orvig C. (2014), Chem. Soc. Rev. 43(1), 260-290].

Rare earth elements (scandium—Sc, yttrium—Y, lanthanum—La, cerium—Ce, praseodymium—Pr, neodymium—Nd, promethium—Pm, samarium—Sm, europium—Eu, gadolinium—Gd, terbium—Tb, dysprosium—Dy, holmium—Ho, erbium—Er, thulium—Tm, ytterbium—Yb and lutetium—Lu) are a group of metals that offer a broad range of medical applications. Radiopharmaceuticals based on ⁹⁰Y, ¹⁵³Sm and ¹⁷⁷Lu are approved by FDA, clinical trials are ongoing with ¹⁶⁶Ho, and others show advantageous properties for Positron Emission Tomography (PET), Single-Photon Emission Computed Tomography (SPECT) or therapy (⁴⁴Sc, ⁴⁷Sc, ⁸⁶Y, ¹⁴⁹Pm, ¹⁵⁹Gd, ¹⁴⁹Tb, ¹⁶¹Tb, ¹⁶⁵Dy, ¹⁶¹Ho, ¹⁶⁹Er and ¹⁷⁵Yb). Stable, non-radioactive Gd chelates are in clinical use as contrast agents for Magnetic Resonance Imaging (MRI). Stable isotopes of rare earth elements also serve as labels for analytical purposes. Compounds of interest labeled in this way can be visualized, traced and quantified based on unique luminescence or isotope mass of the elements that have zero background in biological systems. The unique isotope mass is especially useful, as it allows many compounds to be quantified simultaneously in a single analysis (multiplexing), typically with the use of inductively-coupled plasma mass spectrometry (ICP-MS) [Bodenmiller B. et al. (2012), Nat. Biotechnol. 30(9), 858-867]. Other metal elements from s-, p- and d-block of the periodic system, such as ⁸⁹Sr, ²²³Ra, ^117mSn, ²¹²Pb, ²¹³Bi, ⁶⁴Cu, ²²⁵Ac, find use in radiopharmaceutical compounds for imaging or therapy.

For practical use, metal chelates must be very stable, so that the metal ion cannot easily escape from the chelator and detach from the carrier molecule. In this respect, thermodynamic stability constant provides insufficient information, because most applications proceed under conditions far from thermodynamic equilibrium (e.g. in-vivo). Instead, kinetic inertness that characterizes the rate at which the metal ion escapes from the chelate under given conditions must be considered. Kinetic inertness strongly correlates with rigidity of the chelator. Acyclic chelators of the type DTPA (diethylenetriaminepentaacetic acid) have more flexible structure and provide lower kinetic inertness than macrocyclic chelators of the type DOTA, which are more rigid. Chelates with high kinetic inertness are desirable particularly for in-vivo applications, where the metal chelate is challenged with excess of competing biogenic chelators and metal ions. For this reason, the rigid and kinetically inert macrocyclic chelators are preferred to the flexible acyclic ones. For example, practically all radiopharmaceuticals based on the radionuclide ¹⁷Lu (half-life 6.7 days) that are approved or in development make use of the macrocyclic chelator DOTA, as the metal must remain bound to the targeting molecule in-vivo for weeks in order to have the desired curative effect. Similarly, in MRI contrast agents, macrocyclic chelates of gadolinium(III) are preferred to the acyclic DTPA type. It has been recently found that significant amount of free gadolinium is released in-vivo from the acyclic agents and deposited in human brain for long time. [Fur M. L., Caravan P. (2019), Metallomics 11(2), 240-254] In response to this finding and to prevent potential harm to patients, the use of the acyclic MRI contrast agents has been severely restricted around the globe by drug-regulating agencies. It is therefore likely that the importance of kinetic inertness of metal chelates will grow in medical and other applications, and chelators providing higher inertness will be needed.

Methods to further increase kinetic inertness rely on reinforcement and rigidification of the macrocyclic chelators with additional rings. For example, a cross-bridged macrocyclic chelator cb-TE2A (4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane) provides much more inert chelates with copper(II) ion than the non-cross-bridged analogues [Boswell C. A. et al. (2004), J. Med. Chem. 47(6), 1465-1474]. Another similar chelator cb-TEDPA (6,6′-((1,4,8,11-Tetraazabicyclo[6.6.2]hexadecane-4,11-diyl)bis(methylene))dipicolinic acid) was shown to provide exceptionally inert lanthanide(III) chelates [Rodríguez-Rodríguez A. et al. (2016), Inorg. Chem. 55(5), 2227-2239]. Another cyclen-based cross-bridged chelator provided extremely inert copper(II) chelates [Esteves, C. V. et al. (2013), Inorg. Chem. 52(9), 5138-5153]. A common feature of these chelators is that the bridge is independent from the coordinating pendant arms and is oriented on the opposite side from the pendant arms in the chelate. Chelators where the bridge connected the pendant arms themselves have also been made, but the effect on stability of the chelates was strongly negative [Vipond, J. et al. (2007), Inorg. Chem. 46(7), 2584-2595].

There are also practical limitations when too high kinetic inertness becomes counterproductive. This is because the energy barrier that the metal ion must overcome on the way out of the chelate is similar to the barrier that it has to overcome on the way in during chelate formation. Generally, the more inert a chelate is, the more difficult it is to make. The formation kinetics can be accelerated with high temperature and long reaction times. However, such reaction conditions are often incompatible with sensitive targeting vectors (e.g. antibodies) and/or half-life of metal radionuclides in preparation of radiopharmaceuticals.

There remains a strong need for new types of chelators, which would form highly kinetically inert metal complexes quickly and under mild synthetic conditions.

DISCLOSURE OF INVENTION

We have circumvented problems of the background art with a new type of chelators, which form a bridge after complexation of the metal ion that rigidifies the structure and increases kinetic inertness. The bridge is formed between two coordinating pendant arms based on cycloaddition reaction between alkyne and azide substituents on the opposite pendant arms. This reaction does not require catalyzation by Cu(I) ions as is usually the case, and occurs spontaneously after formation of a non-bridged chelate. The chelator therefore acts as a one-way trap for the metal ion. Initial formation of the non-bridged chelate is relatively fast. Then, a bridge is formed that traps the metal inside the chelator. For rare earth elements, the resulting bridged chelates show extremely high kinetic inertness that is up to 6 orders of magnitude higher than for the analogous chelates with DOTA. Such unusually high inertness allows new uses of the chelates as analytical labels that can withstand harsh hydrolytic conditions in concentrated acids and can be quantified in the lysate as intact chelates with liquid chromatography-mass spectrometry (LC-MS). The use of LC-MS is advantageous, as it is much more common instrument than ICP-MS. The extremely high inertness is also advantageous for potential in-vivo use of the chelates, such as MRI contrast agents or radiopharmaceuticals, as no free metal is released in-vivo from the coordination compounds, therefore no metal deposit occurs in human or animal body.

The compounds according to the present invention are capable of acting as extremely efficient molecular traps, which can coordinate metal ions in an extremely stable, rigid and well defined manner. The ligands can be prepared in relatively a few number of steps of organic synthesis. After coordination of the metal ion, the click reaction is performed between the azide group and a triple bond present in opposite pendant arms of the macrocycle, forming a triazole bridge, and enclosing the metal ion within the cage (forming the so-called click-zipped complex). The formation of triazole is irreversible and is depicted in Scheme 1 below.

Scheme 1. Schematic representation of the click-zip principle illustrated on the example of ligand TD647.

In first aspect, the subject of the present invention relates to compounds of general formula (I)

• • wherein
  • Y is selected from a group consisting of nitrogen (N); N-oxide (N⁺—O—);
  • R¹ is selected from the group consisting of H; halogen; —OH; —N₃; —(CH₂)_nN₃, wherein n is an integer in the range of from 1 to 3; —NR₂, wherein R is independently selected from H or C₁ to C₆ alkyl, which may be branched or linear; —(CH₂)_nNR₂, wherein n and R are as defined above; C₆ to C₁₀ aryl, which can optionally be substituted with —NH₂, —NO₂, —N₃,

—COOH, —CH₂Cl and/or —CH₂COOH; C₇ to C₁₀ arylalkyl, which can optionally be substituted with —NH₂, —NO₂, —N₃,

—COOH, —CH₂Cl and/or —CH₂COOH;

• • —CF₃; —COOR, wherein R is as defined above; —(CH₂)_nCOOR, wherein n and R are as defined above;

—CH₂CH(OMe)₂;

—SH; —SO₃H; —SO₂Ar, wherein Ar is phenyl; NO₂; R² is

wherein n is an integer in the range of from 1 to 3; preferably, R² is

more preferably R² is

• • A are independently selected from the group consisting of H; —(CH₂)_nCOOH, wherein n is an integer from 1 to 3; —CH(CH₃)COOH; —CH((CH₂)_nCH₃)COOH, wherein n is as defined above; —CH₂P(═O)(OR)₂, wherein R is as defined above; —CH((CH₂)_nCOOH)COOH, wherein n is an integer from 1 to 3;
  • —CH((CH₂)_nNH₂)COOH, wherein n is an integer from 1 to 3;
  • —CH₂C(═O)(NH₂); —CH₂C(═O)(NH)—CH₂COOH; —CH₂P(═O)(OH)(Ar), wherein Ar is phenyl, which can optionally be substituted with C₁ to C₆ alkyl;
  • Z is selected from a group consisting of

• • wherein
  • R³ is

• • R⁴ is selected from the group consisting of H; halogen; piperidinyl; trimethylsilyl; triisopropylsilyl; phenyl; C₁ to C₆ alkyl, which may be branched or linear; C₃ to C₆ cycloalkyl; —CF₃; —(CH₂)_nNHR⁶, wherein n is an integer in the range of from 1 to 3 and R⁶ is selected from H, fluorenylmethyloxycarbonyl, tert-butyloxycarbonyl and benzyloxycarbonyl; —C(CH₃)₂(NHR⁶), wherein R⁶ is as defined above; adamantyl;

• • —(CH₂)_nCOOH, wherein n is as defined above; C₆ to C₁₀ aryl, which can optionally be substituted with —NH₂, —NO₂, —N₃,

—COOH, —CH₂Cl and/or —CH₂COOH;

• • R⁵ is R¹ or

wherein R⁴ is as defined above; preferably R⁵ is H; —CF₃; halogen; —OH; C₇ to C₁₀ arylalkyl, which can optionally be substituted with —NH₂, —NO₂, —COOH, —CH₂Cl and/or —CH₂COOH; or R

• • and/or R² and R³ together form a 1,2,3-triazole group of formula

wherein R⁴ is defined above;

• • with the proviso that at most one A is H.

When the compounds of this invention contain a chiral centre, then all enantiomers, mixtures of enantiomers and racemates fall within the framework of the present invention. The present invention further includes the compounds of general formula (I) in the form of salts with alkali metals, ammonium or amines, as well as in the form of addition salts with acids.

The term “halogen” means any iozotop of F, Cl, Br, and I; in particular, this term includes non-radioactive izotopes, such as ¹⁹F, ³⁵Cl, ³⁷Cl, ⁷⁹Br, ⁸¹Br, ¹²⁷I; and radioizotopes, such as ¹⁸F, ³⁶Cl, ⁷⁷Br, ⁸³Br, ¹²³I, ¹²⁴I, ¹²⁵I, ¹³¹I.

In one embodiment, A are independently selected from the group consisting of H; —(CH₂)_nCOOH, wherein n is an integer from 1 to 3; —CH(CH₃)COOH; —CH((CH₂)_nCH₃)COOH, wherein n is an integer from 1 to 3; —CH₂P(═O)(OR)₂, wherein R is as defined above; —CH₂C(═O)(NH₂); —CH₂C(═O)(NH)—CH₂COOH; —CH₂P(═O)(OH)(Ar), wherein Ar is phenyl, which can optionally be substituted with C₁ to C₆ alkyl.

In one embodiment, R¹ is selected from the group consisting of H; halogen; —OH; —N₃; —CH₂N₃; —NR₂, wherein R is independently selected from H or C₁ to C₆ alkyl, which may be branched or linear; —CH₂NR₂, wherein R are as defined above; C₆ to C₁₀ aryl, which can optionally be substituted with —NH₂, —NO₂, —COOH and/or —CH₂COOH; C₇ to C₁₀ arylalkyl, which can optionally be substituted with —NH₂, —NO₂, —COOH, —CH₂Cl and/or —CH₂COOH; —CF₃; —COOR, wherein R is as defined above; —(CH₂)_nCOOR, wherein n and R are as defined above;

—CH₂CH(OMe)₂;

—SH; —SO₃H; —SO₂Ar, wherein Ar is phenyl; NO₂;

• • preferably R¹ is selected from H; halogen; —OH; —N₃; —CH₂N₃; —N(CH₃)₂; phenyl; carboxyphenyl; —CF₃; —COOR, wherein R is as defined above; and

In one embodiment, R⁴ is selected from the group consisting of H; halogen; piperidinyl; trimethylsilyl; triisopropylsilyl; phenyl; C₁ to C₆ alkyl, which may be branched or linear; C₃ to C₆ cycloalkyl; —CF₃; —CH₂NHR⁶, wherein R⁶ is selected from H, fluorenylmethyloxycarbonyl, tert-butyloxycarbonyl and benzyloxycarbonyl; —C(CH₃)₂(NHR⁶), wherein R⁶ is as defined above; adamantyl;

preferably R⁴ is selected from the group consisting of H; trifluoromethyl; 4-piperidinyl; —CH₂—NH₂; phenyl; cyclopropyl; adamantyl; terc-butyl; trimethylsilyl (TMS); triisopropylsilyl (TIPS); halogen (F, Cl, Br, I); —C(CH₃)₂NH₂; and —C(CH₃)₂NHBoc. More preferably, R⁴ is hydrogen.

In one embodiment of the present invention, the compounds of general formula (I) comprises the following substituents:

• • Y is nitrogen (N);
  • R¹ is selected from the group consisting of H; halogen; —OH; —N₃; —CH₂N₃; —NR₂, wherein R is independently selected from H or C₁ to C₆ alkyl, which may be branched or linear; C₆ to C₁₀ aryl, which can optionally be substituted with —NH₂, —NO₂, —COOH and/or —CH₂COOH; C₇ to C₁₀ arylalkyl, which can optionally be substituted with —NH₂, —NO₂, —COOH, —CH₂Cl and/or —CH₂COOH;
  • —CF₃; —COOR, wherein R is as defined above;

—CH₂CH(OMe)₂;

R² is

• • A are independently selected from the group consisting of H; —(CH₂)_nCOOH, wherein n is an integer from 1 to 3; —CH(CH₃)COOH; —CH((CH₂)_nCH₃)COOH, wherein n is as defined above; —CH₂P(═O)(OR)₂, wherein R is as defined above; —CH₂C(═O)(NH₂); —CH₂C(═O)(NH)—CH₂COOH; —CH₂P(═O)(OH)(Ar), wherein Ar is phenyl, which can optionally be substituted with C₁ to C₆ alkyl;
  • Z is selected from a group consisting of

• • wherein
  • R³ is

• • R⁴ is selected from the group consisting of H; halogen; piperidinyl; trimethylsilyl; triisopropylsilyl; phenyl; C₁ to C₆ alkyl, which may be branched or linear; C₃ to C₆ cycloalkyl; —CF₃; —CH₂NHR⁶, wherein R⁶ is selected from H, fluorenylmethyloxykarbonyl and benzyloxycarbonyl; —C(CH₃)₂(NHR⁶), wherein R⁶ is as defined above; adamantyl;

• • R⁵ is H; —CF₃; halogen; —OH; C₇ to C₁₀ arylalkyl, which can optionally be substituted with —NH₂, —NO₂, —COOH, —CH₂Cl and/or —CH₂COOH; or

wherein R⁴ is as defined above;

• • and/or R² and R³ together form a 1,2,3-triazole group of formula

wherein R⁴ is defined above;

• • with the proviso that at most one A is H.

In one preferred embodiment, Y is nitrogen, thus forming a pendant arm comprising a pyridyl moiety, substituted with R¹ and R².

In one embodiment, R¹ is in meta-position from Y, and para-position from R²—CH₂—.

In one embodiment, R¹ is in meta-position from Y, and orto-position from R²—CH₂—.

In another embodiment, R¹ is in para-position from Y.

In one preferred embodiment, R² is

Preferably, R² is

and R¹ is selected from the group comprising H, phenyl, carboxyphenyl, halogen (preferably Cl), trifluoromethyl, carboxyl, carboxylic ester or amine, more preferably R¹ is H or carboxyphenyl.

In one embodiment, Z is

In one preferred embodiment, Z is

and R³ and R⁵ are as defined above. Preferably, Z is

even more preferably, Z is

In the compound of general formula (I), A can be the same or different. Preferably, A are the same.

In one embodiment, Z is

In one embodiment, Z is

In one embodiment, A is selected from the group comprising —(CH₂)COOH; —(CH₂)₂COOH; —CH₂P(═O)(OEt)₂; —CH₂P(═O)(OH)₂; —CH₂P(═O)(OH)(OEt); —CH₂P(═O)(Ph)(OH); —(CH₂)COONH₂; —(CH₂)C(═O)NH—CH₂COOH; —(CH₂)COO^tBu; —CH(CH₂COOH)COOH.

Preferably, A is selected from the group comprising —(CH₂)COOH; —CH₂P(═O)(OEt)₂; —CH₂P(═O)(OH)₂; —CH₂P(═O)(OH)(OEt); and —CH₂P(═O)(Ph)(OH). Most preferably, A is —(CH₂)COOH.

In one embodiment, Y is nitrogen; R¹ is selected from the group consisting of H; Cl; —N(CH₃)₂; phenyl, which can optionally be substituted with —COOH or —CH₂COOH; benzyl, which can optionally be substituted with —COOH or —CH₂COOH; —CF₃; —COOCH₃; —COOCH(CH₃)₂;

• • —COOtBu:

—SH;

• • A are independently selected from the group consisting of H; —(CH₂)_nCOOH, wherein n is 1 or 2; —CH₂P(═O)(OH)₂; —CH₂P(═O)(OH)(OEt); —CH₂P(═O)(OEt)₂; —CH₂C(═O)(NH₂); —CH₂C(═O)(NH)—CH₂COOH; —CH₂P(═O)(OH)(Ph);
  • Z is selected from a group consisting of

• • wherein
  • R³ is

• • R⁴ is selected from the group consisting of H; halogen; piperidinyl; trimethylsilyl; triisopropylsilyl; phenyl; cyclopropyl, terc-butyl; —CF₃; —CH₂NH₂; —CH₂N(H)(Fmoc); —C(CH₃)₂(NH₂); —C(CH₃)₂(NHBoc); adamantyl; R⁵ is H or

wherein R⁴ is as defined above;

• • with the proviso that at most one A is H.

In one preferred embodiment, Z is

R³ is

R⁴ and R⁵ are as defined above, preferably R⁴ and R⁵ are H.

In another embodiment, R² and R³ together form a 1,2,3-triazole group of formula

wherein R⁴ is as defined above, preferably R⁴ is hydrogen. In such embodiment, a bridge is formed between two opposite nitrogen atoms of the cyclen moiety, and the compound of general formula (I) thus forms a cage-like structure. The bridge is an entity of general formula (IIa) or (IIb)

• • wherein
  • L is a linker selected from the group consisting of

• • and R¹, R⁴ and R⁵ are as defined above. The linker L is derived from the group Z defined above.

Preferably, L is

more preferably L is

In one preferred embodiment, the compound of general formula (I) is selected from the group comprising compounds with the following combinations of substituents:

• • Y is N⁺—O⁻; R¹, R⁴ and R⁵ is H:

Compound	A	Z	R2	R3
TD604	—(CH2)COOH

• • Y is N; R¹, R⁴ and R⁵ is H:

Compound	A	Z	R2	R3
TD556	—(CH2)COOH
TD1204	—(CH2)COOH
TD703	—(CH2)COOH and H
TD705	—CH2P(═O)(OEt)2 and —(CH2)COOtBu
TD714	—CH2P(═O)(OH)2 and —(CH2)COOH
TD921	—CH2P(═O)(Ph)(OH)
TD580	—CH2P(═O)(OEt)2
TD582	—CH2P(═O)(OH)(OEt)
TD581	—CH2P(═O)(OH)2
TD801	—(CH2)2COOH
TD1346	—CH(CH3)COOH
TD1408	—(CH2)COOH
cz-TD556	—(CH2)COOH

• • Y is N; Z is

and R² is

Compound	R1	A
TD827		—(CH2)COOH
TD575	Ph	—CH2P(═O)(OEt)2
TD576	Ph	—CH2P(═O)(OH)2
TD764	Cl	—(CH2)COOH
TD1063	—CF3	—(CH2)COOH
TD1092	—COOCH3	—(CH2)COOH
TD1148	—COOiPr	—(CH2)COOH
TD1160	—COOtBu	—(CH2)COOH
TD1176	—N(CH3)2	—(CH2)COOH
TD647	Ph	—(CH2)COOH
TD742	4-carboxyphenyl	—(CH2)COOH
TD779	Ph	—(CH2)COONH2
TD778	Ph	—(CH2)CONH—CH2COOH
TD1504	H	—CH(CH2COOH)COOH;
		—CH(CH3)COOH

• • Y is N; and R² and R³ together form a 1,2,3-triazole group of formula

Compound	R1	A	Z	R4
cz-TD425	Ph	—(CH2)COOH		H
cz-TD764	Cl	—(CH2)COOH		H
cz-TD1063	—CF3	—(CH2)COOH		H
TD1188	H	—(CH2)COOH		—CF3
TD650	Ph	—(CH2)COOH		H

• • Y is N; and R² and R³ together form a 1,2,3-triazole group of formula

	Compound	R1	A	Z
	TD871	Ph	—(CH2)COOH

• • Y is N; R¹ is phenyl; and R² is

and R³ is

Compound	A	Z
TD425	—(CH2)COOH
TD669	—(CH2)COOH

• • Y is N; A is —(CH₂)COOH; R¹ is H; and R² is

Compound	Z	R3	R4	R5
TD810			H
TD718			TMS	H
TD728			TIPS	H
TD1204			I	H
TD944			Ph	H
TD943			cyclopropyl	H
TD959			tBu	H
TD992			adamantyl	H
TD1105			—C(CH3)2N HBoc	H
TD1127			4- piperidinyl	H

• • Y is N; A is —(CH₂)COOH; R² is

and Z is

Compound	R1	R3	R4
TD722	Ph		—CH2NH2
TD1054	Ph		—C(CH3)2NH2
TD744	4-carboxyphenyl		—CH2—NH2

• • Y is N; A is —CH(CH₃)COOH; R² is

and Z is

Compound	R1	R3	R4	R5	R6
TD1451	—CF3		—C(CH3)2(NHR6)	—COOH	tert- butyloxycarbonyl

In the most preferred embodiment, the compound of general formula (I) is selected from the group comprising compounds, wherein Y is nitrogen, Z is

and the remaining substituents are present in the following combinations:

Com-
pound	R1	A	R2	R3	R4	R5
TD556	H	—(CH2)COOH			H	H
TD810	H	—(CH2)COOH			H
TD827		—(CH2)COOH			H	H
TD718	H	—(CH2)COOH			TMS	H
TD728	H	—(CH2)COOH			TIPS	H
TD1204	H	—(CH2)COOH			I	H
TD944	H	—(CH2)COOH			Ph	H
TD943	H	—(CH2)COOH			cyclopropyl	H
TD959	H	—(CH2)COOH			tBu	H
TD992	H	—(CH2)COOH			adamantyl	H
TD705	H	—CH2P(═O)(OEt)2 and —(CH2)COOtBu			H	H
TD714	H	—CH2P(═O)(OH)2 and —(CH2)COOH			H	H
TD921	H	—CH2P(═O)(Ph)(OH)			H	H
TD580	H	—CH2P(═O)(OEt)2			H	H
TD582	H	—CH2P(═O)(OH)(OEt)			H	H
TD581	H	—CH2P(═O)(OH)2			H	H
TD575	Ph	—CH2P(═O)(OEt)2			H	H
TD576	Ph	—CH2P(═O)(OH)2			H	H
TD764	Cl	—(CH2)COOH			H	H
TD1063	—CF3	—(CH2)COOH			H	H
TD1092	—COOCH3	—(CH2)COOH			H	H
TD1148	—COOiPr	—(CH2)COOH			H	H
TD1160	—COOtBu	—(CH2)COOH			H	H
TD1176	—N(CH3)2	—(CH2)COOH			H	H
TD647	Ph	—(CH2)COOH			H	H
TD722	Ph	—(CH2)COOH			—CH2NH2	H
TD1054	Ph	—(CH2)COOH			—C(CH3)2NH2	H
TD1105	H	—(CH2)COOH			—C(CH3)2NHBoc	H
TD1127	H	—(CH2)COOH			4-piperidinyl	H
TD742	4- carboxyphenyl	—(CH2)COOH			H	H
TD744	4- carboxyphenyl	—(CH2)COOH			—CH2—NH2	H
TD779	Ph	—(CH2)COONH2			H	H
TD778	Ph	—(CH2)CONH— CH2COOH			H	H
cz- TD556	H	—(CH2)COOH		H	H
cz- TD764	Cl	—(CH2)COOH		H	H
cz- TD1063	—CF3	—(CH2)COOH		H	H
TD1188	H	—(CH2)COOH		—CF3	H
TD650	Ph	—(CH2)COOH		H	H
TD871	Ph	—(CH2)COOH		H	H

In another aspect, the subject of the present invention is a method of synthesis of the compounds of general formula (I), comprising the following steps:

• • i) providing an alkyne intermediate of general formula Z—Cl, wherein Z is as defined above;
  • ii) providing an azide intermediate of general formula (III)

• • wherein Y, R¹ and R² are as defined above;
  • iii) providing a cyclen derivative of general formula (IV)

• • wherein pA is selected from the group comprising —(CH₂)_nCOO^tBu, wherein n is an integer from 1 to 3; benzyloxycarbonyl; —CH(CH₃)COO^tBu; —CH(CH₃)COOR, wherein R is tert-butyl, methyl or ethyl; —CH((CH₂)_nCH₃)COOR, wherein n and R are as defined above; —CH((CH₂)_nCOOR)COOR, wherein n is as defined above and R are independently selected from tert-butyl, methyl or ethyl; —CH₂P(═O)(OR)₂, wherein R is C₁ to C₆ alkyl, which may be branched or linear; —CH₂C(═O)(NH₂); —CH₂C(═O)(NH)—CH₂COOH; —CH₂P(═O)(OH)(Ar), wherein Ar is phenyl, which can optionally be substituted with C₁ to C₆ alkyl; preferably pA is selected from the group comprising —CH₂COOtBu; —CH₂P(O)(OEt)₂; —(CH₂)₂COOtBu;
  • iv-A) reacting the cyclen derivative of general formula (IV) with alkyne intermediate Z—Cl to obtain an intermediate of general formula (V)

• • wherein Z and pA are as defined above;
  • or
  • iv-B) reacting the cyclen derivative of general formula (IV) with the azide intermediate of general formula (III) to obtain an intermediate of general formula (VI)

• • wherein Y, R¹, R² and pA are as defined above;
  • v-A) reacting the intermediate of general formula (V) with the azide intermediate of general formula (III) to obtain an intermediate of general formula (VII)

• • wherein Y, R¹, R², pA and Z are as defined above;
  • or
  • v-B) reacting the intermediate of general formula (VI) with the alkyne intermediate Z—Cl to obtain the intermediate of general formula (VII);
  • vi) optionally, hydrolysis of protecting groups, resulting in the compound of general formula (I).

In general, compounds of general formula Z—Cl can be obtained commercially or can be synthesised using Pd(0) catalyzed Sonogashira cross-coupling reaction from corresponding 2-halopyridines (preferably Br, I) and terminal alkynes or silyl-protected acetylenes.

Compounds of general formula (III) can be obtained from 2,6-bis(halomethyl)pyridines (preferably Cl) by desymetrization using sodium azide as a source of azide moiety.

Cyclene derivatives of general formula (IV) are commercially available or may be prepared by reaction of cyclen or trans-N-bis-protected cyclen (preferably carbamate protected) with alkyl haloacetates (alkylation), alkyl acrylates (Michael addition) or trialkylphosphites in the presence of (para)formaldehyde (Kabachnik-Fields reaction).

Steps iv-A), iv-B), v-A) and v-B) take place in a solvent selected from the group comprising MeCN (preferably), DMSO or DMF. The reaction takes place at room temperature for usually several hours up to several days.

Step vi) of deprotecting pA groups is optional, for example if pA is —CH₂P(O)(OEt)₂, then if no deprotection takes place, the resulting A in general formula (I) equals pA. Specific conditions for deprotection of the protecting group depend on the chemical nature of the protecting group, and are known to the person skilled in the art. Typically, terc-butyl ester protecting groups and Boc protecting group are hydrolyzed under acidic conditions (TFA) or thermally, methyl or isopropyl protecting groups are hydrolyzed under alkaline conditions, ethyl phosphonate ester are converted to corresponding phosphonic acids by transesterification using trimethylsilylbromide in presence of pyridine base.

Another subject of the present invention is a coordination compound of the compound of the general formula (I) as defined above with a metal cation, selected from the group consisting of lanthanide(III) cations, Na⁺, Ba²⁺, Pb²⁺, Sr²⁺, Ca²⁺, Cd²⁺, Zn²⁺, Mn²⁺, Pt²⁺, Cu²⁺, Ni²⁺, Sc³⁺, Y³⁺, Bi³⁺, In³⁺, Ru³⁺, Ir³⁺, Ga³⁺, Tl³⁺, Pd²⁺; preferably the metal cation is selected from the group consisting of La³⁺, Ce³⁺, Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Gd³⁺, Tb³⁺, Dy³⁺, Ho³⁺, Er³⁺, Tm³⁺, Yb³⁺, Lu³⁺, Y³⁺, Sc³⁺, Bi³⁺, In³⁺, Tl³⁺, Pb²⁺, Ca²⁺, Cd²⁺, Zn²⁺, Cu²⁺, Ni²⁺, Mn²⁺, Pd²⁺, Na⁺.

The metal ions shall be undestood as comprising any izotope of the particular metal, including stable isotopes such as ⁴⁰Ca, ⁴²Ca, ⁴³Ca, ⁴⁴Ca, ⁴⁶Ca, ⁴⁸Ca, ⁴⁵Sc, ⁸⁹y, ¹³⁸La, ¹³⁹La, ¹³⁶Ce, ¹³⁸Ce, ¹⁴⁰Ce, ¹⁴²Ce, ¹⁴¹Pr, ¹⁴²Nd, ¹⁴³Nd, ¹⁴⁴Nd, ¹⁴⁵Nd, ¹⁴⁶Nd, ¹⁴⁸Nd, ¹⁵⁰Nd, ¹⁴⁴Sm, ¹⁴⁷Sm, ¹⁴⁸Sm, ¹⁴⁹Sm, ¹⁵⁰Sm, ¹⁵²Sm, ¹⁵⁴Sm, ¹⁵¹Eu, ¹⁵³Eu, ¹⁵²Gd, ¹⁵⁴Gd, ¹⁵⁵Gd, ¹⁵⁶Gd ¹⁵⁷Gd, ¹⁵⁸Gd, ¹⁶⁰Gd, ¹⁵⁹Tb, ¹⁵⁶Dy, ¹⁵⁸Dy, ¹⁶⁰Dy, ¹⁶¹Dy, ¹⁶²Dy, ¹⁶³Dy, ¹⁶⁴Dy, ¹⁶⁵Ho, ¹⁶²Er, ¹⁶⁴Er, ¹⁶⁶Er, ¹⁶⁷Er, ¹⁶⁸Er, ¹⁷⁰Er, ¹⁶⁹Tm, ¹⁶⁸Yb, ¹⁷⁰Yb, ¹⁷¹Yb, ¹⁷²Yb, ¹⁷³Yb, ¹⁷⁴Yb, ¹⁷⁶Yb, ¹⁷⁵Lu, ¹⁷⁶Lu, and radioisotopes such as ⁴⁴Sc, ⁴⁷Sc, ⁶⁴Cu, ⁶⁷Cu, ⁸⁶Y, ⁹⁰Y, ¹⁴⁰Nd, ¹⁴⁹Pm, ¹⁵¹Pm, ¹⁵³Sm, ¹⁵⁹Gd, ¹⁴⁹Tb, ¹⁶¹Tb, ¹⁶⁵Dy, ¹⁶¹Ho, ¹⁶⁶Ho, ¹⁶⁹Er, ¹⁶⁷Tm, ¹⁷⁵Yb, ¹⁷⁷Lu.

Lanthanides (Ln) are defined as chemical elements comprising 15 metallic chemical elements with atomic numbers in the range of from 57 to 71 (from lanthanum through lutetium).

Preferably, the coordination compound has a general formula (VIII)

• • wherein M is the metal cation, R¹, R⁴, R⁵ and A are as defined above, and n is selected from 1, 2, 3 and 4;
  • more preferably, the coordination compound has a general formula (VIIIa)

The coordination compounds according to the present invention comprise also solvates and salts of pharmaceutically acceptable acids. The positive charge of the metal cation is counterbalanced by two negative charges arising from A pendant arms (e.g. acetates). Therefore, the overall charge of the coordination compound is −1 (for monovalent metal ions), 0 (for divalent metal ions) or +1 (trivalent metal ions). The counterion, compensating for the overall charge of the coordination compound, is selected from the group, comprising anions derived from the following pharmaceutically acceptable acids: 1-hydroxy-2-naphthoic acid; 2,2-dichloroacetic acid; 2-hydroxyethanesulfonic acid; 2-oxoglutaric acid; 4-acetamidobenzoic acid; 4-aminosalicylic acid; acetic acid; adipic acid; ascorbic acid (L); aspartic acid (L); benzenesulfonic acid; benzoic acid; camphoric acid (+); camphor-10-sulfonic acid (+); capric acid (decanoic acid); caproic acid (hexanoic acid); caprylic acid (octanoic acid); carbonic acid; cinnamic acid; citric acid; cyclamic acid; dodecylsulfuric acid; ethane-1,2-disulfonic acid; ethanesulfonic acid; formic acid; fumaric acid; galactaric acid; gentisic acid; glucoheptonic acid (D); gluconic acid (D); glucuronic acid (D); glutamic acid; glutaric acid; glycerophosphoric acid; glycolic acid; hippuric acid; hydrobromic acid; hydrochloric acid; isobutyric acid; lactic acid (DL); lactobionic acid; lauric acid; maleic acid; malic acid (−L); malonic acid; mandelic acid (DL); methanesulfonic acid; naphthalene-1,5-disulfonic acid; naphthalene-2-sulfonic acid; nicotinic acid; nitric acid; oleic acid; oxalic acid; palmitic acid; pamoic acid; phosphoric acid; proprionic acid; pyroglutamic acid (−L); salicylic acid; sebacic acid; stearic acid; succinic acid; sulfuric acid; tartaric acid (+L); thiocyanic acid; toluenesulfonic acid (p); undecylenic acid; trifluoroacetic acid.

The coordination compounds can be prepared according to Scheme 1 above from the free ligand of general formula (I) (preferably the non-caged, therefore preferably without the trazole bridge) and a metal salt (typically water soluble metal salt, preferably selected from a group comprising chloride, nitrate, acetate, formate, trifluoroacetate, trifluoromethylsulfonate, more preferably chloride or nitrate salt). By stirring of these reactants in an aqueous environment (pH 5-7) at temperature in the range of from 25° C. to 100° C., the metal cation coordinates into the compound of general formula (I) and the R² and R³ substituents then “click-zip” the metal cation inside the cage by forming the triazole bridge (reaction temperatures and times are strongly dependent on the choice of ligand and metal cation).

However, the suitable ligands are not limited to the non-caged compounds of general formula (I), eventhough they are preferred because wider range of metal cations (such as lanthanides) may form the caged coordination compounds. The bridged (caged) compounds of general formula (I) with 1,5-triazole bridge are capable of forming coordination compounds with metal cations, typically selected from the group comprising Tl³⁺, Pb²⁺, Bi³⁺, In³⁺, Cd²⁺, Ca²⁺, Cu²⁺, Ni²⁺, Mn²⁺,Pd²⁺, Na⁺. The bridged (caged) compounds of general formula (I) with 1,4-triazole bridge are capable of forming coordination compounds with metal cations, typically selected from the group comprising La³⁺, Ce³⁺, Pr³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Gd³⁺, Tb³⁺, Dy³⁺, Ho³⁺, Er³⁺, Tm³⁺, Yb³⁺, Lu³⁺, Y³⁺, Tl³⁺, Pb²⁺, Bi³⁺, In³⁺, Cd²⁺, Ca²⁺, Cu²⁺, Ni²⁺, Mn²⁺, Pd²⁺, Na⁺.

The resulting coordination compounds are very inert and stable, therefore suitable for various applications, such as MRI contract agents, radiodiagnostics or radiotherapy, peptide or protein containing drug tracing.

The coordination of the compound of general formula (I) to a metal cation takes place via the macrocyclic nitrogen atoms of the cyclene moiety, oxygen atoms present in groups A (pendant arms) and Y group (when Y is N-oxide), and via nitrogen atoms of Y group (when Y is nitrogen) and nitrogen atom present in Z group.

In one embodiment, the coordination compounds according to the present invention may undergo a post-clickzip transformation. It means that after the metal cation is coordinated within the cage of the compound of general formula (I) by either following the Scheme 1 or coordinating with the caged compound of general formula (I), some functional groups, if present, may undergo a further reaction. Typically, such functional group is a halogen, preferably Cl, NO₂ or SH, present within substituent R¹ or R⁵ of the coordination compound, however, post-clickzip transformations may include reactions of R¹, R⁴, R⁵ and/or A groups (such as amidic coupling reactions of non-coordinated carboxylic or amino groups).

For example, when R¹ is halogen, preferably Cl; or R¹ is C₆ to C₁₀ aryl, substituted with —CH₂Cl, then the coordination compound of general formula (VIII) may undergo post-click transformation using Pd(O) catalyzed Suzuki cross-coupling reaction with phenylboronic acids (3-borono-5-nitrobenzoic acid or 2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)acetic acid or 2-(4-boronophenyl)acetic acid), during which the halogen is replaced, thus the resulting coordination compound of general formula (VIII) would have R¹═COOH or C₆ to C₁₀ aryl, substituted with —COOH or —CH₂COOH. The resulting carboxylate moiety can be then utilized in amide coupling reaction for synthesis of peptide conjugates. Conjugates with oligoarginines are capable of crossing cell membrane, allowing metal cages to be incorporated to the cells.

Another possible post-click transformation is the replacement of halogen present within R¹, R⁴ and/or R⁵ substituent by —N₃ group by reaction with NaN₃. The resulting azide can be used for coupling of the metal cage to another alkyne-bearing moiety using copper-catalysed azide-alkyne cycloaddition (CuAAC) reaction. Another possible post-click transformation is the hydrolysis of TIPS protecting group present in R¹, R⁴ and/or R⁵ substituent and protecting the triple bond (R¹, R³ and/or R⁵ is

The hydrolysis is performed using aqueous K₂CO₃, and results in R¹, R³ and/or R⁵ being

The resulting deprotected triple bond is suitable for further conjugations via reaction with the alkyne, for example click reactions with azides and forming triazole bridges (e.g. CuAAC reaction).

In another embodiment, the post-click transformation may be addition reaction of methanol to R¹, R⁴ and/or R⁵, wherein R¹, R³ and/or R⁵ is

thus transforming the triple bond to dimethyl acetal (protected version of an aldehyde). This demonstrates conversion of one functional group (alkyne) to another (aldehyde). Aldehydes are usable for conjugation reactions based on formation of Schiff bases with amines, hydrazines and acid hydrazides.

In yet another embodiment, the post-click transformation may be deuteration reaction of CH₂ groups of the pendant arms in D₂O in presence of DBU, transforming them into CD₂ groups. This conversion does not alter the physico-chemical properties of the molecule (in terms of stability or reactivity), but changes the overall mass of the molecule, to be entirely distinguishable from the parent non-deuterated molecule using mass spectrometry. This means, that the metal ion cage with one particular metal can be used as two different mass tags.

In yet another embodiment, the post-click transformation may be a selective reduction of pyridyl cycle of Z substituent, wherein Z is

and R³ and R⁵ are as defined above, using NaBH₄ or NaBD₄ as the reducing agent, thus transforming the Z group into

respectively. Similiarly to the deuteration of CH₂ groups, this conversion changes the mass of the molecule for metal tags purposes.

In yet another embodiment, the post-click transformation may be reaction of NH₂ group, if present, of R¹ and/or R⁴ and/or R⁵ and/or A, wherein R¹ and/or R⁴ and/or R contains —NH₂ or —(CH₂)_nNH₂, with FmocCl, resulting in transformation of —NH₂ group into —NHFmoc group. Fmoc group is the most commonly encountered amine protecting group used in solid-phase peptide synthesis (SPPS). Introducting of Fmoc group therefore facilitates use of the metal cages for SPPS.

In yet another embodiment, the post-click transformation may be reaction of NH₂ group, if present, of R¹ and/or R⁴ and/or R⁵ and/or A, with a carboxyl group of another molecule of general formula (I) or of its metal complex as defined above, resulting in conjugation of two or more compounds of general formula (I) or of their metal complexes into conjugates bound via a peptide (amide) bond.

In yet another embodiment, the post-click transformation may be reaction of non-coordinating —COOH group, if present, in R¹ and/or R⁴ and/or R⁵ and/or A, with an amino group of an aminoacid or peptide, thus forming a peptide bond for conjugation purposes.

In yet another embodiment, the post-click transformation may be S-alkylation reaction of a halogen, preferably Cl, of R¹, R⁴ and/or R⁵ substituent with a thiol, resulting in trasforming the halogen into sulfide. The thiol may be e.g. Na₂S, NaSH, N-Boc-cysteine or a cysteine-containing peptide and the reaction may take place in presence of DIPEA. Incorporating cysteine (aminoacid) into the structure of the coordination compound according to the present invention opens futher possibilities for amide bonds (e.g. peptide attachment).

In yet another embodiment, the post-click transformation may be reaction of

group of R¹, R³ and/or R⁵, wherein R¹, R³ and/or R⁵ contains

with an azide, preferably with alkyl- or arylazide, thereby forming a triazole bridge connecting the alkyl- or aryl- to R¹, R³ and/or R⁵ group. The arylazide is preferably C6 to C10 arylazide, e.g. benzyl azide, optionally substituted with —COOH or —CH₂COOH. The alkyl azide is preferably C1 to C7 alkyl azide, wherein the alkyl may be linear or branched.

In yet another embodiment, the post-click transformation may be reaction of —N₃ group of R¹ or R⁵, wherein R¹ or R⁵ contains —N₃ group, with a substituent comprising a carbon-carbon triple bond, thereby forming a triazole bridge connecting the substituent with the coordination compound. The substituent comprising a triple bond may be for example C7 to C10 arylalkynyl, optionally substituted with —COOH or —CH₂COOH, e.g. phenylacetylene, wherein the phenyl moiety may optionally be substituted with —COOH or —CH₂COOH.

In yet another embodiment, the post-clickzip transformation may be reaction of —SH group of R¹ and/or R⁵, with a substituent comprising maleimide, thereby forming thiosuccinimide linkage connecting the substituent with the coordination compound; or reaction of —SH group of R¹ and/or R⁵, with a substituent comprising another —SH group, thereby forming a disulfide bridge connecting the substituent with the coordination compound; or reaction of —SH group of R¹ and/or R⁵, with alkyl- or arylhalogenide, thereby forming a thioether linkage connecting the alkyl- or aryl- to the coordination compound.

In yet another embodiment, the post-clickzip transformation may be reaction of —NO₂ group of R¹ and/or R⁵, with a substituent comprising —SH group, thereby forming a thioether linkage connecting the substituent with the coordination compound.

In one embodiment, the post-click transformation may include reaction with another coordination compound of the present invention, thereby forming a chain or a dimer. The coordination compound chain or dimer may contain the same metal cation in both click-zipped cages or it may contain different metal cations in each of the chelates. The advantage of the chains and dimers lies in the possibility to combine properties of the two caged chelates, such as their unique weights to produce mass tags with higher variability of weights.

Typically, the coordination compounds are bound into the chain by forming a triazole bridge between R¹ or R group of the first coordination compound and R¹ or R⁵ group of the following coordination compound (the use of R⁵ group is only possible for Z being

The general basic structure of the coordination compound chain is thus (IXa) or (IXb)

In one embodiment, the coordination compounds are bound into the chain by amide bonds formed between a substituent of one coordination compound containing an amine group (R¹ and/or R⁴ and/or R⁵ and/or A) and a substituent of another coordination compound containing a carboxyl group (R¹ and/or R⁴ and/or R⁵ and/or A).

The chain usually contains two coordination compounds according to the present invention, however it may contain three, four or more coordination compounds.

In yet another embodiment the two types of linkage, described above, are possible in one chain, for example two neighbouring coordination compounds may be linked by one triazole bridge, leaving R⁵ or R¹ substituent available for linking another coordination compound according to the present invention, either via a triazole bridge or, if amino or carboxyl groups are present, via an amide bond.

In one embodiment, the coordination compounds are bound into the chain by disulfide bonds (—S—S—) formed between a substituent R¹ or R⁵ of one coordination compound containing —SH group, and a substituent R¹ or R⁵ of another coordination compound containing —SH group.

The coordination compound dimer contains two coordination compounds according to the present invention, bound together by forming a triazole bridge between R¹ group of the first coordination compound and R⁵ group of the second coordination compound, and, at the same time, by forming a triazole bridge between R⁵ group of the first coordination compound and R¹ group of the second coordination compound.

The general structure of the coordination compound dimer is thus (X)

The synthesis of the coordination compound chain or dimer is based on a click reaction between an azido group of the first coordination compound and a triple bond of the second coordination compound, thereby forming a triazole bridge, linking the two coordination compound into a dimer. The triazole bridge is selected from the group comprising: 1,2,3-triazole group of formula

formed between —N₃ group of R¹ or R⁴ or R⁵ of first coordination compound and the triple bond of R¹ or R⁴ or R⁵ of the second coordination compound. Preferably, the metal cations are different, for example the metal cations are selected from Tb³⁺ and ¹⁷⁶Yb³⁺.

Yet another object of the present invention is a conjugate suitable for use as markers for drug tracing. Many drugs are based on peptides or proteins, and their biodistribution can be traced by attachment of a fluorescent or radioactive marker to the peptide or protein structure. The coordination compounds and dimers of the present invention are suitable for their attachment to the peptide or protein of a drug to be traced. The isolated cell culture or a tissue can then be analysed for the presence of the metal complex using conventional methods, such as LC-MS, which is commonly used and relatively unexpensive instrument. The cells or tissues can be entirely hydrolyzed in a strong acid without any decomposition of the coordination compound according to the present invention. The coordination compound can then be detected in a hydrolyzed sample. Such method is unexpensive and reliable thanks to the extremely high stability of the coordination compounds. LC-MS method also allows for using a plurality of different coordination compounds with different metal isotops (multiplexing), which may then be all analyzed during one LC-MS analysis.

The conjugate according to the present invention contains the coordination compound according to the present invention as defined above or the coordination compound dimer or chain as defined above, conjugated to a peptide or to a protein. The conjugation takes place via an amide bond, formed between the amino group of the peptide or the protein and a carboxyl group of the coordination compound or of the chain or dimer or vice versa. Thus, the coordination compound or the chain or dimer need to contain either —NH₂ or —COOH group prior to peptide or protein conjugation. Preferably, the —NH₂ or —COOH group is part of the R¹ and/or R⁴ and/or R⁵ group, therefore the conjugates are formed from coordination compounds or coordination compound dimers, which have R¹ and/or R⁴ and/or R⁵ group selected from the group comprising —NH₂; —(CH₂)_nNH₂; —COOH; —(CH₂)_nCOOH; C₆ to C₁₀ aryl, substituted with —NH₂, —COOH, —(CH₂)_nNH₂, or —(CH₂)_nCOOH; wherein n is an integer in the range of from 1 to 3.

The conjugation reaction conditions are known to the person skilled in the art, typically the reaction takes place at 25° C. in DMSO, using commonly used peptide coupling agents (preferebaly HATU, PyAOP) in the presence of organic base (triethylamine, ethyldiisopropylamine). Reaction are usually completed within several minutes. The peptide is preferably selected from the group comprising oligopeptides of 3 to 20 aminoacids;

The protein is preferably selected from the group comprising antibodies, preferably monoclonal antibodies.

Another object of the present invention is a method of drug tracing, preferably of tracing of peptide-based or protein-based drugs, which comprises the following steps:

• • i) providing a cell culture or a tissue to be analyzed, containing at least one conjugate defined above, wherein the peptide or the protein is of the peptide-based or protein-based drug to be traced;
  • ii) hydrolyzing the cell culture or tissue from step i) using a strong acid, preferably non-oxidizing aq. HCl, obtaining a hydrolyzate;
  • iii) qualitative and/or quantitative analysis of the hydrolyzate of step ii) for the presence of the coordination compound or of the coordination compound dimer according to the present invention, preferably using LC-MS.

Further object of the present invention is the in vitro use of the coordination compound or of the coordination compound dimer or of the conjugate according to the present invention in pharmacy, preferably for development and testing of new drugs, more preferably for drug marking and tracing.

Another object of the present invention is the use of the coordination compounds or of the coordination compound dimers according to the present invention in medical diagnostics, preferably as MRI contrast agents. Preferably, Gd³⁺ coordination compounds or dimers shall be used as MRI contrast agents, as Gd has a very high relaxivity. The extremely high kinetic inertness of the coordination compounds (approximately 100× higher than for GdDOTA, a commonly used MRI contrast agent) allows for using even higher dosages and no free gadolinium, which itself is toxic for humans or animals, is released from the coordination compounds according to the present invention. The claimed coordination compounds are thus expected to be safe for use in human or animal beings.

Another object of the present invention is the use of the coordination compound or the coordination compound chain or the coordination compound dimer according to the present invention, wherein M is a radionuclide, preferably selected from the group comprising ⁴⁴Sc, ⁴⁷Sc, ⁶⁴Cu, ⁶⁷Cu, ⁸⁶Y, ⁹⁰Y, ¹⁴⁰Nd, ¹⁴⁹Pm, ¹⁵¹Pm, ¹⁵³Sm, ¹⁵⁹Gd, ¹⁴⁹Tb, ¹⁶¹Tb, ¹⁶⁵Dy ¹⁶¹Ho, ¹⁶⁶Ho, ¹⁶⁹Er, ¹⁶⁷Tm, ¹⁷⁵Yb, ¹⁷⁷Lu, in medicine as radiodiagnostic and/or radiopharmaceutic agents. Alternatively, a radionuclide may also be present in the side chain of the coordination compound such as a radioizotope of a halogen, e.g. R¹ and/or R⁵ may be ¹⁸F.

The present invention is further demostrated by the following examples.

EXAMPLES

Example 1: Synthesis of Intermediates of Alkyne Pendant Arms

Synthesis of TD701: Pear-shape glass flask (50 mL) was charged with (6-Bromopyridin-2-yl)methanol (2.47 g; 13.1 mmol; 1.0 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (149 mg; 782 μmol; 6.0 mol %) and [Pd(PPh₃)₂Cl₂] (225 mg; 321 μmol; 2.4 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (25 mL) through septum followed by addition of Ethynyltrimethylsilane (2.0 mL; 14.5 mmol; 1.1 equiv.) and TEA (5.5 mL; 39.5 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 3 h at RT. The mixture was then transferred to a separatory funnel with EtOAc (150 mL) and H₂O (100 mL). After shaking, the dark colored (and not entirely homogenous) organic layer was separated and the aqueous layer was further extracted with EtOAc (5×50 mL). Combined organic layers were filtered through cotton plug and the filtrate was further dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Resulting dark brown oily residue was purified on flash chromatography (330 g SiO₂, 100% DCM to 10% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as dark yellow oil. Yield: 2.16 g (80%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 0.24 (CH₃, s, 9H); 4.52 (CH₂, d, 2H, ³J_HH=6); 5.48 (OH, t, 1H, ³J_HH=6); 7.39 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.46 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.80 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C −0.3 (CH₃, s); 63.9 (CH₂, s); 93.4 and 104.5 (C≡C; 2×s); 120.2 (arom., s); 125.4 (arom., s); 137.2 (arom., s); 140.8 (arom., s); 162.7 (arom., s). ESI-HRMS: 206.0995 [M+H]⁺ (theor. [C₁₁H₁₆N₁O₁Si₁]⁺=206.0996).

Synthesis of TD557: In a round-bottom glass flask (100 mL), TD701 (2.16 g; 10.5 mmol; 1.0 equiv.) was dissolved in DCM (40 mL). Freshly prepared solution of SOCl₂ (1.50 mL; 20.7 mmol; 2.0 equiv.) in DCM (10 mL) was then added and the open flask was stirred 1 h at RT. Dil. aq. solution of NaHCO₃ (50 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The brown residue (already pure according to ¹H NMR) was purified on flash chromatography (330 g SiO₂, 60% P.E. in DCM to 20% P.E. in DCM) to remove the intensively colored impurities. Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residual nearly colorless oil was left in a freezer to solidify. Resulting solid was crushed and further dried on high vacuum overnight to give product in the form of free base as fine white powder. Yield: 2.14 g (87%; 1 step; based on TD701). NMR (DMSO-d₆): ¹H δ_H 0.25 (CH₃, s, 9H); 4.76 (CH₂, s, 2H); 7.50 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.55 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.86 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C −0.4 (CH₃, s); 46.3 (CH₂, s); 94.3 and 103.8 (C≡C; 2×s); 123.3 (arom., s); 126.7 (arom., s); 138.1 (arom., s); 141.5 (arom., s); 157.0 (arom., s). ESI-HRMS: 224.0657 [M+H]⁺ (theor. [C₁₁H₁₅N₁Cl₁Si₁]⁺=224.0657).

Synthesis of TD558: In a pear-shaped glass flask (100 mL), TD557 (1.05 g; 4.69 mmol; 1.0 equiv.) was dissolved in MeCN (40 mL). Freshly prepared solution of KF (406 mg; 7.0 mmol; 1.5 equiv.) in H₂O (7 mL) was then added and the flask was vigorously stirred 2 h at RT. The mixture was concentrated to ˜10 mL and then diluted with DCM (50 mL) and dil. aq. NaHCO₃ (50 mL). The mixture was transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as pale yellow oil. Yield: 702 mg (99%; 1 step; based on TD557). NMR (DMSO-d₆): ¹H δ_H 4.37 (C≡CH, s, 1H); 4.76 (CH₂, s, 2H); 7.53 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.57 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.87 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} 46.3 (CH₂, s); 80.6 and 82.6 (C≡CH; 2×s); 123.4 (arom., s); 126.8 (arom., s); 138.1 (arom., s); 141.3 (arom., s); 157.0 (arom., s). ESI-HRMS: 152.0262 [M+H]⁺ (theor. [C₈H₇N₁Cl₁]⁺=152.0262).

Synthesis of TD712: Pear-shape glass flask (10 mL) was charged with (6-Bromopyridin-2-yl)methanol (284 mg; 1.51 mmol; 1.0 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (14.5 mg; 76 μmol; 5.0 mol %) and [Pd(PPh₃)₂Cl₂](21 mg; 30 μmol; 2.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (4 mL) through septum followed by addition of Ethynyltriisopropylsilane (370 μL; 1.65 mmol; 1.1 equiv.) and TEA (630 μL; 4.52 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 16 h at RT. The mixture was then transferred to a separatory funnel with EtOAc (30 mL) and H₂O (30 mL). After shaking, the dark colored (and not entirely homogenous) organic layer was separated and the aqueous layer was further extracted with EtOAc (5×25 mL). Combined organic layers were filtered through cotton plug and the filtrate was further dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Resulting dark brown oily residue was purified on flash chromatography (120 g SiO₂, 100% DCM to 10% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 387 mg (89%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 0.92-1.26 (i-Pr, m, 21H); 4.53 (CH₂, d, 2H, ³J_HH=6); 5.48 (OH, t, 1H, ³J_HH=6); 7.40 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.47 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.80 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C 10.7 (i-Pr, s); 18.5 (i-Pr, s); 64.0 (CH₂, s); 89.4 and 106.6 (C≡C; 2×s); 120.2 (arom., s); 125.8 (arom., s); 137.2 (arom., s); 140.9 (arom., s); 162.7 (arom., s). ESI-HRMS: 290.1932 [M+H]⁺ (theor. [C₁₇H₂₈N₁O₁Si₁]⁺=290.1935).

Synthesis of TD723: In a round-bottom glass flask (25 mL), TD712 (384 g; 1.33 mmol; 1.0 equiv.) was dissolved in DCM (5 mL). Freshly prepared solution of SOCl₂ (200 μL; 2.75 mmol; 2.1 equiv.) in DCM (1 mL) was then added and the open flask was stirred 1 h at RT. Dil. aq. solution of NaHCO₃ (10 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The brown residue (already pure according to ¹H NMR) was purified on flash chromatography (120 g SiO₂, 20% DCM in P.E. to 30% DCM in P.E.) to remove the intensively colored impurities. Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residual colorless oil was further dried on high vacuum overnight to give product in the form of free base as colourless solid. Yield: 356 mg (87%; 1 step; based on TD712). NMR (DMSO-d₆): ¹H δ_H 0.91-1.28 (i-Pr, m, 21H); 4.78 (CH₂, s); 7.52 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.57 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.86 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 308.1593 [M+H]⁺ (theor. [C₁₇H₂₇N₁Cl₁Si₁]⁺=308.1596).

Synthesis of TD530: Pear-shape glass flask (50 mL) was charged with (6-Bromopyridin-2-yl)methanol (1.00 g; 5.35 mmol; 1.0 equiv.), N-Boc-propargylamine (1.00 g; 6.44 mmol; 1.2 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (102 mg; 536 μmol; 10.0 mol %) and [Pd(PPh₃)₂Cl₂](187 mg; 266 μmol; 5.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (27 mL) through septum followed by addition of TEA (2.24 mL; 16.1 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 18 h at RT. The mixture was then transferred to a separatory funnel with EtOAc (30 mL) and H₂O (50 mL). After shaking, the dark colored (and not entirely homogenous) organic layer was separated and the aqueous layer was further extracted with EtOAc (3×30 mL). Combined organic layers were filtered through cotton plug and the filtrate was further dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Resulting dark brown oily residue was purified on flash chromatography (220 g SiO₂, 100% DCM to 100% EtOAc). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 610 mg (43%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 1.40 (CH₃, s, 9H); 3.99 (CH₂, d, 2H, ³J_HH=6); 4.51 (CH₂, d, 2H, ³J_HH=6); 5.47 (OH, t, 1H, ³J_HH=6); 7.32 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.40 (NH, t, 1H, ³J_HH=6); 7.44 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.79 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C 28.2 (CH₃, s); 29.9 (CH₂, s); 64.0 (CH₂, s); 78.4 (C—CH₃, s); 81.3 and 86.9 (C≡C; 2×s); 119.8 (arom., s); 125.0 (arom., s); 137.2 (arom., s); 141.1 (arom., s); 155.3 (CO, s); 162.5 (arom., s). ESI-HRMS: 263.1390 [M+H]⁺ (theor. [C₁₄H₁₉N₂O₃]⁺=263.1390).

Synthesis of TD538: In a round-bottom glass flask (250 mL), TD530 (568 mg; 2.17 mmol; 1.0 equiv.) was dissolved in DCM (20 mL) followed by addition of TEA (900 μL; 6.46 mmol; 3.0 equiv.). Freshly prepared solution of MsCl (355 μL; 4.33 mmol; 2.0 equiv.) in DCM (5 mL) was then added. Resulting solution was stirred 20 min at RT. Mixture was then diluted with DCM (50 mL) followed by addition of dil. aq. solution of NaHCO₃ (50 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 341.1 [M+H]⁺ (theor. [C₁₅H₂₁N₂O₅S₁]⁺=341.1). All of TD538 obtained in this way was directly used for TD539 without further purification or characterization.

Synthesis of TD1045: Pear-shaped glass flask (25 mL) was charged with (6-Bromopyridin-2-yl)methanol (500 mg; 2.67 mmol; 1.0 equiv.), 1,1-Dimethylpropargylamine (420 μL; 3.99 mmol; 1.5 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (21 mg; 110 μmol; 4.0 mol %) and [Pd(PPh₃)₂Cl₂](19 mg; 27 μmol; 1.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (10 mL) through septum followed by addition of TEA (1.10 mL; 7.89 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 18 h at RT. The mixture was filtered with syringe microfilter (PTFE) and the solid phase was further washed with MeCN. Filtrate was evaporated to dryness and the resulting dark brown solid residue was purified on flash chromatography (120 g SiO₂, 100% EtOAc to 40% EtOAc in MeOH). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow solidified oil. Yield: 283 mg (56%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 1.38 (CH₃, s, 6H); 3.17 (NH₂, s, 2H); 4.51 (CH₂, s, 2H); 5.44 (OH, bs, 1H); 7.26 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.40 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.76 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 191.1180 [M+H]⁺ (theor. [C₁₁H₁₅N₂O₁]⁺=191.1180).

Synthesis of TD1048: Pear-shaped glass flask (25 mL) was charged with TD1045 (280 mg; 1.47 mmol; 1.0 equiv.) followed by addition of MeCN (10 mL) and solution of Boc₂O (2.0 M in dry THF; 1.0 mL; 2.00 mmol; 1.4 equiv.). The resulting mixture was stirred 16 h at RT. Mixture was then evaporated to dryness and the resulting yellow residue was purified on flash chromatography (120 g SiO₂, 100% DCM to 100% EtOAc). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless solid. Yield: 242 mg (57%; 1 step; based on TD1045). NMR (DMSO-d₆): ¹H δ_H 1.40 (CH₃, s, 9H), 1.53 (CH₃, s, 6H); 4.51 (CH₂, d, 2H, ³J_HH=4); 5.44 (OH, t, 1H, ³J_HH=4); 7.12 (NH, bs, 1H); 7.25 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.41 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.77 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 291.1704 [M+H]⁺ (theor. [C₁₆H₂₃N₂O₃]⁺=291.1703).

Synthesis of TD1050: In a glass vial (20 mL), TD1048 (19 mg; 65 μmol; 1.0 equiv.) was dissolved in DCM (3 mL) followed by addition of TEA (28 μL; 201 μmol; 3.1 equiv.). Freshly prepared solution of MsCl (10 μL; 129 μmol; 2.0 equiv.) in DCM (1 mL) was then added. Resulting solution was stirred 20 min at RT. Mixture was then diluted with DCM (15 mL) followed by addition of dil. aq. solution of NaHCO₃ (15 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×20 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 369.1 [M+H]⁺ (theor. [C₁₇H₂₅N₂O₅S₁]⁺=369.1). All of TD1050 obtained in this way was directly used for TD1054 (and analogically for TD1105) without further purification or characterization.

Synthesis of TD966: Pear-shape glass flask (100 mL) was charged with (6-Bromopyridin-2-yl)methanol

1 (1.00 g; 5.35 mmol; 1.0 equiv.), N-Boc-4-ethynylpiperidine (1.23 g; 5.88 mmol; 1.1 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (41 mg; 215 μmol; 4.0 mol %) and [Pd(PPh₃)₂Cl₂] (75 mg; 107 μmol; 2.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (40 mL) through septum followed by addition of TEA (2.20 mL; 15.7 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 2 d at RT. The mixture was then transferred to a separatory funnel with EtOAc (30 mL) and H₂O (50 mL). After shaking, the dark colored (and not entirely homogenous) organic layer was separated and the aqueous layer was further extracted with EtOAc (3×30 mL). Combined organic layers were filtered through cotton plug and the filtrate was further dried with anhydrous Na₂SO₄, filtered through glass frit (S₃) and evaporated to dryness. Resulting dark brown oily residue was purified on flash chromatography (220 g SiO₂, 100% DCM to 100% EtOAc). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 1.47 g (87%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 1.40 (CH₃, s, 9H); 1.44-1.57 (CH₂, m, 2H); 1.75-1.89 (CH₂, m, 2H); 2.87 (CH—C≡C tt, 1H, ³J_HH=8, ³J_HH=4); 3.01-3.17 (CH₂, m, 2H); 3.59-3.73 (CH₂, m, 2H); 4.51 (CH₂—O, d, 2H, ³J_HH=6); 5.44 (OH, t, 1H, ³J_HH=6); 7.32 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.41 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.76 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 317.1860 [M+H]⁺ (theor. [C₁₈H₂₅N₂O₃]⁺=317.1860).

Synthesis of TD1117: In a glass vial (20 mL), TD952 (50.0 mg; 158 μmol; 1.0 equiv.) was dissolved in DCM (6 mL) followed by addition of TEA (66 μL; 473 μmol; 3.0 equiv.) and neat MsCl (25 μL; 323 μmol; 2.0 equiv.). Resulting solution was stirred 20 min at RT followed by addition of DCM (10 mL) dil. aq. solution of NaHCO₃ (10 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 395.2 [M+H]⁺ (theor. [C₁₉H₂₇N₂O₅S₁]⁺=395.2). All of TD1117 obtained in this way was directly used for TD1118 without further purification or characterization.

Synthesis of TD936: Glass vial (4 mL) was charged with (6-Bromopyridin-2-yl)methanol (135 mg; 722 μmol; 1.0 equiv.), CuI (5.5 mg; 29 μmol; 4.0 mol %), [Pd(PPh₃)₂Cl₂](10.0 mg; 14 μmol; 2.0 mol %) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added dry THF (3 mL) through septum followed by addition of phenylacetylene (95 μL; 865 μmol; 1.2 equiv.) and TEA (300 μL; 2.15 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The vial was left stirring under septum (but without external argon) for 16 h at RT. The mixture was then filtered through syringe microfilter (PTFE) followed by washing with MeCN. Filtrate was evaporated to dryness, re-dissolved in MeCN (3 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions containing product were neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in a mixture of DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residual solid was briefly dried on high vacuum to give product in the form of free base as a yellow oil. Yield: 141 mg (93%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 4.57 (CH₂, d, 2H, ³J_HH=6); 5.50 (OH, t, 1H, ³J_HH=6); 7.42-7.54 (arom., Ph, m, 2+3H); 7.57-7.64 (Ph, m, 2H); 7.85 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 210.0913 [M+H]⁺ (theor. [C₁₄H₁₂N₁O₁]⁺=210.0913).

Synthesis of TD939: In a glass vial (20 mL), TD936 (22 mg; 105 μmol; 1.0 equiv.) was dissolved in DCM (6 mL) followed by addition of TEA (44 μL; 316 μmol; 3.0 equiv.). and neat MsCl (16 μL; 207 μmol; 2.0 equiv.). Resulting solution was stirred 20 min at RT followed by addition of dil. aq. solution of NaHCO₃ (5 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 288.1 [M+H]⁺ (theor. [C₁₅H₁₄N₁O₃S₁]⁺=288.1). All of TD939 obtained in this way was directly used for TD944 without further purification or characterization.

Synthesis of TD937: Glass vial (4 mL) was charged with (6-Bromopyridin-2-yl)methanol (135 mg; 722 μmol; 1.0 equiv.), CuI (5.5 mg; 29 μmol; 4.0 mol %), [Pd(PPh₃)₂Cl₂](10.0 mg; 14 μmol; 2.0 mol %) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added dry THF (3 mL) through septum followed by addition of Cyclopropylacetylene (75 μL; 886 μmol; 1.2 equiv.) and TEA (300 μL; 2.15 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The vial was left stirring under septum (but without external argon) for 16 h at RT. The mixture was then filtered through syringe microfilter (PTFE) followed by washing with MeCN. Filtrate was evaporated to dryness, re-dissolved in MeCN (3 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions containing product were neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in a mixture of DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residual solid was briefly dried on high vacuum to give product in the form of free base as a yellow oil. Yield: 98 mg (78%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 0.69-0.83 (CH₂—CH, m, 2H); 0.83-0.99 (CH₂—CH, m, 2H); 1.56 (CH, tt, ³J_HH=8, ³J_HH=5); 4.49 (CH₂, d, 2H, ³J_HH=6); 5.42 (OH, t, 1H, ³J_HH=6); 7.27 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.38 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.74 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 174.0913 [M+H]⁺ (theor. [C₁₁H₁₂N₁O₁]⁺=174.0913).

Synthesis of TD940: In a glass vial (20 mL), TD937 (26 mg; 150 μmol; 1.0 equiv.) was dissolved in DCM (9 mL) followed by addition of TEA (63 μL; 452 μmol; 3.0 equiv.) and neat MsCl (23 μL; 297 μmol; 2.0 equiv.). Resulting solution was stirred 20 min at RT followed by addition of dil. aq. solution of NaHCO₃ (5 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 252.0 [M+H]⁺ (theor. [C₁₂H₁₄N₁O₃S₁]⁺=252.1). All of TD940 obtained in this way was directly used for TD943 without further purification or characterization.

Synthesis of TD952: Glass vial (4 mL) was charged with (6-Bromopyridin-2-yl)methanol (150 mg; 802 μmol; 1.0 equiv.), CuI (6.1 mg; 32 μmol; 4.0 mol %), [Pd(PPh₃)₂Cl₂](11.5 mg; 16 μmol; 2.0 mol %) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added dry THF (3 mL) through septum followed by addition of tert-butylacetylene (200 μL; 1.62 mmol; 2.0 equiv.) and TEA (340 μL; 2.44 mmol; 3.0 equiv.) after which the mixture changed color to dark brown. The vial was left stirring under septum (but without external argon) for 24 h at RT. The mixture was then filtered through syringe microfilter (PTFE) followed by washing with MeCN. Filtrate was evaporated to dryness, re-dissolved in MeCN (3 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions containing product were neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in a mixture of DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residual solid was briefly dried on high vacuum to give product in the form of free base as a yellow oil. Yield: 146 mg (96%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 1.30 (CH₃, s, 9H); 4.51 (CH₂, d, 2H, ³J_HH=6); 5.43 (OH, t, 1H, ³J_HH=6); 7.26 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.39 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.74 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 190.1227 [M+H]⁺ (theor. [C₁₂H₁₆N₁O₁]⁺=190.1226).

Synthesis of TD956: In a glass vial (20 mL), TD952 (8 mg; 42 μmol; 1.0 equiv.) was dissolved in DCM (3 mL) followed by addition of TEA (18 μL; 129 μmol; 3.0 equiv.) and neat MsCl (6.5 μL; 84 μmol; 2.0 equiv.). Resulting solution was stirred 20 min at RT followed by addition of DCM (5 mL) dil. aq. solution of NaHCO₃ (5 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 268.1 [M+H]⁺ (theor. [C₁₃H₁₈N₁O₃S₁]⁺=268.1). All of TD956 obtained in this way was directly used for TD959 without further purification or characterization.

Synthesis of TD965: Glass vial (4 mL) was charged with (6-Bromopyridin-2-yl)methanol (53 mg; 283 μmol; 1.0 equiv.), 1-Ethynyladamantane (50 mg; 312 μmol; 1.1 equiv.), CuI (2.7 mg; 14 μmol; 5.0 mol %), [Pd(PPh₃)₂Cl₂](5.0 mg; 7 μmol; 2.5 mol %) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added dry THF (1.5 mL) through septum followed by addition of TEA (120 μL; 861 μmol; 3.0 equiv.) after which the mixture changed color to dark brown. The vial was left stirring under septum (but without external argon) for 2 d at RT. The mixture was then filtered through syringe microfilter (PTFE) followed by washing with MeCN. Filtrate was evaporated to dryness, re-dissolved in MeCN (3 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions containing product were neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in a mixture of DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residual solid was briefly dried on high vacuum to give product in the form of free base as a colourless oil. Yield: 67 mg (89%; 1 step; based on (6-Bromopyridin-2-yl)methanol). NMR (DMSO-d₆): ¹H δ_H 1.61-1.76 (Adm., m, 6H); 1.82-1.93 (Adm., m, 6H); 1.94-2.00 (Adm., m, 3H); 4.50 (CH₂, d, 2H, ³J_HH=6); 5.43 (OH, t, 1H, ³J_HH=6); 7.25 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.38 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.74 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 268.1694 [M+H]⁺ (theor. [C₁₈H₂₂N₁O₁]⁺=268.1696).

Synthesis of TD990: In a glass vial (20 mL), TD965 (21 mg; 79 μmol; 1.0 equiv.) was dissolved in DCM (3 mL) followed by addition of TEA (33 μL; 237 μmol; 3.0 equiv.) and neat MsCl (12 μL; 155 μmol; 2.0 equiv.). Resulting solution was stirred 20 min at RT followed by addition of DCM (10 mL) dil. aq. solution of NaHCO₃ (10 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×15 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 346.1 [M+H]⁺ (theor. [C₁₉H₂₄N₁O₃S₁]⁺=346.1). All of TD990 obtained in this way was directly used for TD992 without further purification or characterization.

Synthesis of TD1194: In a glass vial (4 mL), TD558 (110 mg; 726 μmol; 1.0 equiv.) was dissolved in MeCN (3.3 mL) followed by addition of NIS (180 mg; 800 μmol; 1.1 equiv.) and AcOH (50 μL; 875 μmol; 1.2 equiv.) and the resulting mixture was stirred 3 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions containing product were joined and diluted with DCM (50 mL). The resulting biphasic mixture was transferred to a separatory funnel followed by addition of dil. aq. NaHCO₃ and aq. Na₂S₃O₃. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was briefly dried on high vacuum to give product in the form of free base as a pale red solid. Yield: 61.5 mg (31%; 1 step; based on TD558). NMR (DMSO-d₆): ¹H δ_H 4.74 (CH₂, s, 2H); 7.48 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.54 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 277.9230 [M+H]⁺ (theor. [C₈H₆N₁I₁Cl₁]⁺=277.9228).

Synthesis of TD1178: Glass vial (20 mL) was charged with CuI (60.0 mg; 315 μmol; 40 mol %), Phen (114 mg; 633 μmol; 80.0 mol %), KHCO₃ (159 mg; 1.59 mmol; 2.0 equiv.) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added solution of TD558 (120 mg; 792 μmol; 1.0 equiv.) and Togni I (288 mg; 872 μmol; 1.1 equiv.) in dry DCM (8 mL) through septum and the resulting mixture was stirred 2 d at RT. Mixture was then filtered through syringe microfilter (PTFE) and the solid phase was further washed with DCM. Filtrate was evaporated to dryness and the residue was resuspended in MeCN (3 mL). Mixture was again filtered through syringe microfilter (PTFE) and the filtrate was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions containing product were joined and diluted with DCM (50 mL). The resulting biphasic mixture was transferred to a separatory funnel followed by addition of dil. aq. NaHCO₃. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The resulting yellow oil was briefly dried on high vacuum (until the oil crystallized) to give product in the form of free base as pale yellow solid (portion of the product sublimed as colourless crystals on the upper part of the flask). Yield: 48.5 mg (28%; 1 step; based on TD558). NMR (DMSO-d₆): ¹H δ_H 4.83 (CH₂, s, 2H); 7.78 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.04 (arom., t, 1H, ³J_HH=8). ¹⁹F{¹H} δ_F −49.2 (s). ESI-HRMS: 220.0140 [M+H]⁺ (theor. [C₉H₆N₁F₃Cl₁]⁺=220.0135).

Synthesis of TD797: In a round-bottom glass flask (50 mL), Methyl 4,6-dibromopicolinate (200 mg; 678 μmol; 1.0 equiv.) was dissolved in a mixture of THF (4 mL) and MeOH (2 mL). To the resulting slightly yellow solution was added portion wise (over course of 10 min, with no stopper on the flask) solid NaBH₄ (205 mg; 5.42 mmol; 8.0 equiv.) during which hydrogen gas evolved intensively and the color of the mixture changed to nearly colorless. Mixture was then transferred to a separatory funnel and diluted with DCM (100 mL) and H₂O (100 mL). After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as white solid. Yield: 179 mg (99%; 1 step; based on Methyl 4,6-dibromopicolinate). NMR (DMSO-d₆): ¹H δ_H 4.53 (CH₂, s, 2H); 5.68 (OH, bs, 1H); 7.67 (arom., m, 1H); 7.89 (arom., m, 1H). ESI-HRMS: 265.8809 [M+H]⁺ (theor. [C₆H₆N₁O₁Br₂]⁺=265.8811).

TMS Synthesis of TD804: Glass vial (4 mL) was charged with TD797 (100 mg; 375 μmol; 1.0 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (4.3 mg; 23 μmol; 6.0 mol %) and [Pd(PPh₃)₂C₁₂](8.0 mg; 11 μmol; 3.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (1.5 mL) through septum followed by addition of Ethynyltrimethylsilane (160 μL; 1.16 mmol; 3.1 equiv.) and TEA (160 μL; 1.15 mmol; 3.1 equiv.) after which the mixture changed color to dark brown. The flask was left stirring under septum (but without external argon) for 16 h at RT. The mixture was then transferred to a separatory funnel with EtOAc (50 mL) and H₂O (50 mL). After shaking, the dark colored organic layer was separated and the aqueous layer was further extracted with EtOAc (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Resulting dark brown oily residue was purified on flash chromatography (120 g SiO₂, 100% DCM to 20% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as dark brown oil. Yield: 99 mg (88%; 1 step; based on TD797). NMR (DMSO-d₆): ¹H δ_H 0.24 (CH₃, s, 9H); 0.25 (CH₃, s, 9H); 4.51 (CH₂, d, 2H, ³J_HH=6); 5.53 (OH, t, 1H, ³J_HH=6); 7.40 (arom., d, 1H, ⁴J_HH=2); 7.42 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 302.1389 [M+H]⁺ (theor. [C₁₆H₂₄N₁O₁Si₂]⁺=302.1391).

Synthesis of TD806: In a pear-shaped glass flask (50 mL), TD804 (98 mg; 325 μmol; 1.0 equiv.) was dissolved in DCM (3 mL). Freshly prepared solution of SOCl₂ (47 μL; 647 μmol; 2.0 equiv.) in DCM (1 mL) was then added and the open flask was stirred 1 h at RT. Reaction mixture was diluted with DCM (16 mL) and dil. aq. solution of NaHCO₃ (20 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×20 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as brown oil. Yield: 102 mg (98%; 1 step; based on TD804). NMR (DMSO-d₆): ¹H δ_H 0.25 (CH₃, s, 18H); 4.74 (CH₂, s, 2H); 7.53 (arom., d, 1H, ⁴J_HH=2); 7.60 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 320.1051 [M+H]⁺ (theor. [C₁₆H₂₃N₁O₁Cl₁Si₂]⁺=320.1052).

Synthesis of TD807: In a round-bottom glass flask (50 mL), TD806 (101 mg; 316 μmol; 1.0 equiv.) was dissolved in MeCN (5 mL). Freshly prepared solution of KF (46.4 mg; 800 μmol; 2.5 equiv.) in H₂O (800 μL) was then added and the flask was stirred 5 h at RT. The mixture was concentrated to ˜1 ml and diluted with DCM (50 mL) and dil. aq. NaHCO₃ (50 mL). The mixture was transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as brown solid. Yield: 48 mg (87%; 1 step; based on TD806). NMR (DMSO-d₆): ¹H δ_H 4.48 (C≡CH, s, 1H); 4.75 (C≡CH, s, 1H); 4.76 (CH₂, s, 2H); 7.61 (arom., d, 1H, ⁴J_HH=1); 7.65 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 176.0267 [M+H]⁺ (theor. [C₁₀H₇N₁Cl₁]⁺=176.0267).

Synthesis of TD662: In a glass vial (4 mL), Dipropargylamine (116 μL; 1.12 mmol; 1.0 equiv.) was dissolved in MeCN (2.5 mL) followed by addition of neat 1,2-Dibromoethane (965 μL; 11.2 mmol; 10 equiv.) and NaHCO₃ (113 mg; 1.35 mmol; 1.2 equiv.) and the resulting mixture was stirred 2 days at 80° C. Mixture was then diluted with DCM (50 mL) followed by addition of dil. aq. solution of NaHCO₃ (50 mL). The resulting biphasic mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was further purified by column chromatography (SiO2; 25 g; DCM). Combined fractions with product were evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 69 mg (31%; 1 step; based on Dipropargylamine). NMR (DMSO-d₆): ¹H δ_H 2.86 (CH₂, t, 2H, ³J_HH=7); 3.21 (C≡CH, t, 2H, ⁴J_HH=2); 3.21 (CH₂, t, 4H, ⁴J_HH=2); 3.55 (CH₂, t, 2H, ³J_HH=7). ¹³C{¹H} δ_C 30.3 (CH₂, s); 41.6 (CH₂, s); 53.9 (CH₂, s); 76.4 and 78.5 (C≡CH, 2×s). ESI-HRMS: 200.0070 [M+H]⁺ (theor. [C₈H₁₁N₁Br₁]⁺=200.0070).

Example 2: Synthesis of Intermediates of Azide Pendant Arms

Synthesis of TD406: In a round-bottom glass flask (250 mL), 2,6-Bis(chloromethyl)pyridine (6.17 g; 35.0 mmol; 1.2 equiv.) was dissolved in MeCN (80 mL) followed by addition of solid NaN₃ (1.90 g; 29.2 mmol; 1.0 equiv.) and anhydrous K₂CO₃ (4.04 g; 29.2 mmol; 1.0 equiv.) and the resulting suspension was stirred 5 days at 50° C. The mixture was filtered on glass frit S₃ and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and the orange oily residue was purified by column chromatography (SiO₂, 30% P.E. in DCM to 100% DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as faint yellow oil. Yield: 2.62 g (49%; 1 step; based on NaN₃). Recovery: 2.21 g of 2,6-Bis(chloromethyl)pyridine (36% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 4.53 (CH₂, s, 2H); 4.78 (CH₂, s, 2H); 7.40 (arom., d, 1H, ³J_HH=8; ⁴J_HH=1); 7.52 (arom., d, 1H, ³J_HH=8; ⁴J_HH=1); 7.89 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C 46.6 (CH₂, s); 54.2 (CH₂, s); 121.9 (arom., s); 122.6 (arom., s); 138.5 (arom., s); 155.7 (arom., s); 156.3 (arom., s). ESI-HRMS: 183.0433 [M+H]⁺ (theor. [C₇H₈N₄Cl₁]⁺=183.0432).

Synthesis of TD595: In a glass vial (20 mL), TD406 (30 mg; 162 μmol; 1.0 equiv.) was dissolved in DCM (5 mL) followed by addition of freshly prepared solution of MCPBA (77%; 72 mg; 320 μmol; 2.0 equiv.) in DCM (1 mL). The resulting solution was stirred 3 h at RT. Mixture was then diluted with DCM (20 mL) and dil. aq. NaHCO₃ (25 mL) and transferred to a separatory funnel. After shaking, the bottom layer was separated and aqueous layer was further extracted with DCM (3×20 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. ESI-MS (LC-MS): 199.0 [M+H]⁺ (theor. [C₇H₈N₄O₁Cl₁]⁺=199.0). All of TD595 obtained in this way was directly used for TD596 without further purification or characterization.

Synthesis of TD726: In a round-bottom glass flask (1000 mL), Dimethyl 4-chloropyridine-2,6-dicarboxylate (15.0 g; 65.3 mmol; 1.0 equiv.) was gradually dissolved in a mixture of THF (540 mL) and MeOH (120 mL). The resulting slightly yellow solution was cooled with an ice bath (˜5° C.) followed by portion wise additions (over course of 1 h, with no stopper on the flask) of solid NaBH₄ (12.4 g; 328 mmol; 5.0 equiv.) during which hydrogen gas evolved intensively and the color of the mixture changed to red, orange and eventually yellow. After the addition, the flask was allowed to warm up to RT and was further stirred 16 h at RT. Resulting faint yellow opalescent solution was filtered on glass frit (S3), the filtrate was evaporated to dryness and further co-evaporated with DCM (as a suspension). Residue was dissolved in boiling H₂O (˜600 mL) and the resulting highly alkaline solution was continuously extracted by DCM overnight. The organic layer (containing partly crystallized product) was evaporated to dryness. The residue was mechanically crushed and further dried on high vacuum (till constant mass) to give product in the form of free base as nearly colorless microcrystalline powder. Yield: 10.84 g (96%; 1 step; based on Dimethyl 4-chloropyridine-2,6-dicarboxylate). NMR (DMSO-d₆): ¹H δ_H 4.53 (CH₂, d, 4H, ³J_HH=6); 5.54 (OH, t, 2H, ³J_HH=6); 7.36 (arom., s, 2H). ¹³C{¹H} δ_C 63.7 (CH₂, s); 118.0 (arom., s); 144.0 (arom., s); 163.5 (arom., s). ESI-HRMS: 174.0317 [M+H]⁺ (theor. [C₇H₉N₁O₂Cl₁]⁺=174.0316). EA (C₇H₈N₁O₂Cl₁, M_R=173.6): C 48.4 (48.5); H 4.7 (4.5); N 7.7 (8.1); Cl 20.4 (21.2).

Synthesis of TD759: In a round-bottom glass flask (100 mL), TD726 (626 mg; 3.61 mmol; 11.0 equiv.) was suspended in DCM (20 mL). Freshly prepared solution of SOCl₂ (780 μL; 10.7 mmol; 3.0 equiv.) in DCM (10 mL) was then added and the open flask was stirred 90 cl min at RT, producing clear solution. Dil. aq. solution of NaHCO₃ (40 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The resulting crystalized residue was crushed and further dried on high vacuum overnight to give product in the form of free base as nearly colorless microcrystalline powder. Yield: 711 mg (94%; 1 step; based on TD726). NMR (DMSO-d₆): ¹H δ_H 4.79 (CH₂, s, 4H); 7.70 (arom., s, 2H). ¹³C{¹H} δ_C 45.7 (CH₂, s); 122.8 (arom., s); 144.4 (arom., s); 158.2 (arom., s). ESI-HRMS: 209.9638 [M+H]⁺ (theor. [C₇H₇N₁Cl₃]⁺=209.9639).

Synthesis of TD760: In a glass vial (20 mL), TD759 (708 mg; 3.36 mmol; 1.3 equiv.) was dissolved in MeCN (20 mL) followed by addition of solid NaN₃ (168 mg; 2.58 mmol; 1.0 equiv.) and dried K₂CO₃ (360 mg; 2.61 mmol; 1.0 equiv.) and the resulting suspension was stirred 24 h at 80° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and yellow oily residue was purified by column chromatography (SiO₂, 40% P.E. in DCM to 10% P.E. in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum 1 h to give product in the form of free base as faint yellow oil. Yield: 323 mg (58%; 1 step; based on NaN₃). Recovery: 218 mg of TD759 (31% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 4.56 (CH₂, s, 2H); 4.78 (CH₂, s, 2H); 7.58 (arom., d, 1H, ⁴J_HH=2); 7.69 (arom., d, 1H, ⁴J_HH=8). ¹³C{¹H} δ_C 45.8 (CH₂, s); 53.6 (CH₂, s); 121.9 (arom., s); 122.5 (arom., s); 144.4 (arom., s); 157.9 (arom., s); 158.2 (arom., s). ESI-HRMS: 217.0040 [M+H]⁺ (theor. [C₇H₇N₄Cl₂]⁺=217.0042).

Synthesis of TD1146: In a glass vial (20 mL), TD726 (495 mg; 2.85 mmol; 1.0 equiv.) was dissolved in DMF (11.0 mL; 143 mmol; 50 equiv.) followed by addition of freshly ground KOH (1.6 g; 28.5 mmol; 10 equiv.). The resulting suspension was stirred 3 days at 100° C. in the presence of air (vial septum was punctured by two thick needles). The mixture was then filtered through syringe microfilter (PTFE; the solids were washed with DMF). Filtrate was evaporated to dryness and purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were combined and directly lyophilized to give product in the form of trifluoroacetate salt as white foam. Yield: 187 mg (22%; 1 step; based on TD726). NMR (DMSO-d₆): ¹H δ_H 3.18 (CH₃, s, 6H); 4.59 (CH₂, d, 4H, ³J_HH=6); 5.91 (OH, t, 2H, ³J_HH=6); 6.84 (arom., s, 2H). ESI-HRMS: 183.1128 [M+H]⁺ (theor. [C₉H₁₅N₂O₂]⁺=183.1128). EA (C₉H₁₄N₂O₂·1.0TFA, M_R=296.2): C 44.6 (44.1); H 5.1 (4.9); N 9.5 (9.1); F 19.2 (18.2).

Synthesis of TD1154: In a round-bottom glass flask (100 mL), TD1146·1.0TFA (173.3 mg; 585 μmol; 1.0 equiv.) was suspended in DCM (17 mL) followed by addition of neat N SOCl₂ (780 μL; 2.34 mmol; 4.0 equiv.). The resulting mixture was stirred 90 min at RT, producing clear solution. Dil. aq. solution of NaHCO₃ (20 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as white solid. Yield: 105.6 mg (82%; 1 step; based on TD726). NMR (DMSO-d₆): ¹H δ_H 2.98 (CH₃, s, 6H); 4.60 (CH₂, s, 4H); 6.73 (arom., s, 2H). ESI-HRMS: 219.0450 [M+H]⁺ (theor. [C₉H₁₃N₂Cl₂]⁺=219.0450).

Synthesis of TD1163: In a glass vial (20 mL), TD1154 (103.9 mg; 474 μmol; 1.3 equiv.) was dissolved in MeCN (7 mL) followed by addition of solid NaN₃ (23.7 mg; 365 μmol; 1.0 equiv.) and dried K₂CO₃ (50.3 mg; 364 μmol; 1.0 equiv.) and the resulting suspension was stirred 24 h at 70° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and the residue was purified by column chromatography (SiO₂, 5% EtOAc in DCM to 10% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum 1 h to give product in the form of free base as colourless oil. Yield: 33.8 mg (41%; 1 step; based on NaN₃). Recovery: 11.0 mg of TD1154 (11% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 2.99 (CH₃, s, 6H); 4.32 (CH₂, s, 2H); 4.60 (CH₂, s, 2H); 6.60 (arom., d, 1H, ⁴J_HH=2); 6.73 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 226.0853 [M+H]⁺ (theor. [C₉H₁₃N₅Cl₁]⁺=226.0854).

Synthesis of TD1024: Glass vial (100 mL) was charged with CuI (70 mg; 0.37 mmol; 4.0 mol %) and [Pd(PPh₃)₂Cl₂](125 mg; 0.18 mmol; 2.0 mol %) and magnetic stirrer and three times secured with argon. Solution of Dimethyl 4-iodopyridine-2,6-dicarboxylate (2.93 g; 9.13 mmol; 1.0 equiv.) in mixture of dry THF (40 ml), dry Toluene (40 ml) and dry DMF (2 mL) was subsequently added through septum followed by addition of Ethynyltriisopropylsilane (2.25 mL; 10.0 mmol; 1.1 equiv.) and TEA (3.80 mL; 27.3 mmol; 3.0 equiv.) after which the mixture changed color to pale red. The flask was left stirring under septum (but without external argon) for 20 h at RT. The resulting dark mixture was filtered through syringe microfilter (PTFE) and the filtrate was evaporated to dryness. Residue was dissolved in DCM (250 mL) and the resulting red solution was washed once with aq. solution of Na₂S₂O₃. The organic layer was separated, dried with Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified on flash chromatography (220 g SiO₂, 100% DCM to 20% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give pre-purified product in the form of free base as orange oil. Yield: 3.16 g (92%; 1 step; based on Dimethyl 4-iodopyridine-2,6-dicarboxylate). NMR (DMSO-d₆): ¹H δ_H 0.92-1.27 (i-Pr, m, 21H); 3.92 (CH₃, s, 6H); 8.16 (arom., s, 2H). ¹³C{¹H} δ_C 10.6 (i-Pr, s); 18.4 (i-Pr, s); 52.9 (CH₃, s); 99.0 (C≡C—Si, s); 102.5 (C≡C-arom.; s); 129.3 (arom., s); 132.7 (arom., s); 148.4 (arom., s); 164.0 (CO, s). ESI-HRMS: 376.1939 [M+H]⁺ (theor. [C₂₀H₃₀N₁O₄Si₁]⁺=376.1939).

Synthesis of TD808: In a round-bottom glass flask (250 mL), TD1024 (3.15 g; 8.39 mmol; 1.0 equiv.) was dissolved in a mixture of THF (60 mL) and MeOH (30 mL). Then, solid NaBH₄ (2.55 g; 67.4 mmol; 8 equiv.) was added portion wise over the course of 1 h (during which hydrogen gas evolved intensively) and the color of the mixture changed to dark red. After the addition, the flask was further stirred 1 h at RT. The mixture was evaporated to dryness. Residue was resuspended in DCM (200 mL) and H₂O (200 mL) and transferred to a separatory funnel. After shaking, the bottom phase (as a suspension) was separated. Aqueous phase was further extracted with DCM (3×100 mL). Combined organic layers were diluted with EtOAc (500 mL). The resulting brown solution was then dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as pale brown solid. Yield: 2.61 g (97%; 1 step; based on TD1024). NMR (DMSO-d₆): ¹H δ_H 1.04-1.17 (i-Pr, m, 21H); 4.51 (CH₂, d, 4H, ³J_HH=6); 5.48 (OH, t, 2H, ³J_HH=6); 7.31 (arom., s, 2H). ¹³C{¹H} δ_C 10.6 (i-Pr, s); 18.5 (i-Pr, s); 63.9 (CH₂, s); 94.6 (C≡C—Si, s); 105.1 (C≡C-arom.; s); 119.8 (arom., s); 130.8 (arom., s); 161.9 (arom., s). ESI-HRMS: 320.2036 [M+H]⁺ (theor. [C₁₈H₃₀N₁O₂]⁺=320.2040).

Synthesis of TD815: In a round-bottom glass flask (250 mL), pre-purified TD808 (2.61 g; 8.17 mmol; 1.0 equiv.) was suspended in DCM (100 mL). Freshly prepared solution of SOCl₂ (1.80 mL; 24.8 mmol; 3.0 equiv.) in DCM (10 mL) was then added and the open flask was stirred 1 h at RT. Dil. aq. solution of NaHCO₃ (100 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×75 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 2.87 g (99%; 1 step; based on TD808). NMR (DMSO-d₆): ¹H δ_H 0.97-1.20 (i-Pr, m, 21H); 4.78 (CH₂, s, 4H); 7.59 (arom., s, 2H). ¹³C{¹H} δ_C 10.6 (i-Pr, s); 18.4 (i-Pr, s); 45.9 (CH₂, s); 96.6 (C≡C—Si, s); 103.5 (C≡C-arom.; s); 124.6 (arom., s); 132.0 (arom., s); 157.1 (arom., s). ESI-HRMS: 356.1368 [M+H]⁺ (theor. [C₁₈H₂₈N₁Cl₂Si₁]⁺=356.1368).

Synthesis of TD817: In a round-bottom glass flask (250 mL), TD815 (2.86 g; 8.02 mmol; 1.2 equiv.) was dissolved in MeCN (130 mL) followed by addition of solid NaN₃ (435 mg; 6.69 mmol; 1.0 equiv.) and dried K₂CO₃ (920 mg; 6.67 mmol; 1.0 equiv.) and the resulting suspension was stirred 16 h at 80° C. The mixture was filtered through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and orange oily residue was purified by column chromatography (220 g SiO₂, 30% P.E. in DCM to 10% P.E. in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum 1 h to give product in the form of free base as faint yellow oil. Yield: 1.23 g (51%; 1 step; based on NaN₃). Recovery: 709 mg of TD815 (25% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 1.01-1.21 (i-Pr, m, 21H); 4.55 (CH₂, s, 2H); 4.78 (CH₂, s, 2H); 7.47 (arom., d, 1H, ⁴J_HH=1); 7.58 (arom., d, 1H, ⁴J_HH=1). ¹³C{¹H} δ_C 10.6 (i-Pr, s); 18.4 (i-Pr, s); 46.0 (CH₂, s); 53.7 (CH₂, s); 96.5 (C≡C—Si, s); 103.7 (C≡C-arom.; s); 123.7 (arom., s); 124.3 (arom., s); 131.8 (arom., s); 156.6 (arom., s); 157.1 (arom., s). ESI-HRMS: 363.1763 [M+H]⁺ (theor. [C₁₈H₂₈N₄Cl₁Si₁]⁺=363.1766).

Synthesis of TD1052: In a glass vial (20 mL), Dimethyl 4-iodopyridine-2,6-dicarboxylate (500 mg; 1.56 mmol; 1.0 equiv.), CuI (600 mg; 3.15 mmol, 2.0 equiv.) and [(dppf)PdCl₂] (7.0 mg, 10 μmol; 0.6 mol %) were dissolved in dry DMF (8 mL) followed by addition of Methyl 2,2-difluoro-2-(fluorosulfonyl)acetate (600 mg; 3.12 mmol; 2.0 equiv.) in dry DMF (2 mL). The resulting dark mixture was stirred 16 h at 100° C. After cooling down, the mixture was diluted with DCM (10 mL) and filtered through syringe microfilter (PTFE). The solids were further washed with DCM. Filtrate was further diluted with DCM (50 mL) and washed with dil. aq. NaHCO₃ (5×25 mL). Organic layer was dried with anhydrous Na₂SO₄, filtered through glass frit (S₃) and evaporated to dryness. Residue was purified by column chromatography (120 g SiO₂, 100% DCM to 15% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless solid. Yield: 366 mg (89%; 1 step; based on Dimethyl 4-iodopyridine-2,6-dicarboxylate). NMR (DMSO-d₆): ¹H δ_H 3.97 (CH₃, s, 6H); 8.49 (arom., q, 2H, ⁴J_HH=1). ¹⁹F{¹H} δ_F −63.4 (s). ESI-HRMS: 264.0480 [M+H]⁺ (theor. [C₁₀H₉N₁O₄F₃]⁺=264.0478).

Synthesis of TD1053: In a round-bottom glass flask (100 mL), TD1052 (365 mg; 1.39 mmol; 1.0 equiv.) was dissolved in a mixture of MeOH (5 mL) and THF (10 mL). The resulting colourless solution was cooled with an ice bath (˜5° C.) followed by portion wise additions (over course of 30 min, with no stopper on the flask) of solid NaBH₄ (420 mg; 11.1 mmol; 8.0 equiv.) during which hydrogen gas evolved intensively and the color of the mixture changed to red and orange. After the addition, the flask was allowed to warm up to RT and was further stirred 30 min at RT. Resulting yellow solution was evaporated to dryness. Residue was purified by column chromatography (120 g SiO₂, solid load technique, 100% EtOAc to 15% MeOH in EtOAc). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 171 mg (60%; 1 step; based on TD1052). NMR (DMSO-d₆): ¹H δ_H 4.62 (CH₂, s, 4H); 5.65 (OH, s, 2H); 7.60 (arom., q, 2H, ⁴J_HH=1). ¹⁹F{¹H} δ_F −63.6 (s). ESI-HRMS: 208.0580 [M+H]⁺ (theor. [C₈H₉N₁O₂F₃]⁺=208.0580).

Synthesis of TD1055: In a round-bottom glass flask (100 mL), TD1053 (169 mg; 816 μmol; 1.0 equiv.) was dissolved in DCM (20 mL). Freshly prepared solution of SOCl₂ (237 μL; 3.26 mmol; 4.0 equiv.) in DCM (5 mL) was then added and the resulting mixture was stirred 16 h at RT. Dil. aq. solution of NaHCO₃ (25 mL) was then added and resulting biphasic mixture was vigorously stirred for additional 10 min at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 168 mg (84%; 1 step; based on TD1053). NMR (DMSO-d₆): ¹H δ_H 4.90 (CH₂, s, 4H); 7.94 (arom., s, 2H). ¹⁹F{¹H} δ_F −63.4 (s). APCI-HRMS: 243.9902 [M+H]⁺ (theor. [C₈H₇N₁F₃Cl₂]⁺=243.9902).

Synthesis of TD1057: In a glass vial (4 mL), TD1055 (143 mg; 586 μmol; 1.8 equiv.) was dissolved in MeCN (3.5 mL) followed by addition of solid NaN₃ (21.5 mg; 331 μmol; 1.0 equiv.) and dried K₂CO₃ (46 mg; 333 μmol; 1.0 equiv.) and the resulting suspension was stirred 3 d at 70° C. The mixture was filtered through syringe microfilter (PTFE) and the N₃ solid residue was washed with MeCN. Filtrate was evaporated to dryness and orange oily residue was purified by column chromatography (80 g SiO₂, 30% P.E. in DCM to 40% DCM in P.E.). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum 1 h to give product in the form of free base as colourless oil. Yield: 43.9 g (53%; 1 step; based on NaN₃). Recovery: 32.1 mg of TD1055 (22% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 4.69 (CH₂, s, 2H); 4.90 (CH₂, s, 2H); 7.81 (arom., d, 1H, ⁴J_HH=1); 7.93 (arom., d, 1H, ⁴J_HH=1). ¹⁹F{¹H} δ_F −63.4 (s). APCI-HRMS: 251.0306 [M+H]⁺ (theor. [C₈H₇N₄F₃Cl₁]⁺=251.0306).

Synthesis of TD549:_Pear-shape glass flask (250 mL) was charged with Dimethyl 4-chloropyridine-2,6-dicarboxylate

(5.00 g; 21.8 mmol; 1.0 equiv.), Phenylboronic acid (3.20 g; 26.2 mmol; 1.2 equiv.) and XPhos Pd G2 (510 mg; 648 μmol; 3.0 mol %) and was then three times secured with argon. Under constant flow of argon was then added dry DMF (110 mL) through septum followed by addition of freshly dried (using heat gun under high vacuum) Cs₂CO₃ (15.6 g; 47.9 mmol; 2.2 equiv.; the flask was briefly opened for addition). The mixture was then stirred 20 h under septum (but without external argon) at 80° C. Resulting dark mixture was filtered through glass frit (S3) and the filtrate was poured to a stirred beaker with H₂O (500 mL). Precipitate was collected on glass frit (S₂), washed with H₂O and further dried on high vacuum overnight to give product in the form of free base as off white solid. Yield: 3.01 g (51%; 1 step; based on Dimethyl 4-chloropyridine-2,6-dicarboxylate). NMR (DMSO-d₆): ¹H δ_H 3.95 (CH₃, s, 6H); 7.45-7.57 (Ph, m, 3H); 7.82-8.00 (Ph, m, 2H); 8.48 (arom., s, 2H); ¹³C{¹H} δ_C 52.7 (CH₃, s); 125.0 (arom., s); 127.2 (Ph., s); 129.5 (Ph., s); 130.2 (Ph., s); 135.5 (Ph., s); 148.6 (arom., s); 150.0 (arom., s); 164.7 (CO., s). ESI-HRMS: 272.0916 [M+H]⁺ (theor. [C₁₅H₁₄N₁O₄]⁺=272.0917).

Synthesis of TD563: In a round-bottom glass flask (500 mL), TD549 (2.98 g; 11.0 mmol; 1.0 equiv.) was dissolved in a mixture of MeOH (100 mL) and THF (100 mL). The resulting slightly yellow solution was cooled with an ice bath (˜5° C.) followed by portion wise additions (over course of 30 min, with no stopper on the flask) of solid NaBH₄ (2.90 g; 76.7 mmol; 9.0 equiv.) during which hydrogen gas evolved intensively and the color of the mixture changed to red and orange. After the addition, the flask was allowed to warm up to RT and was further stirred 30 min at RT. Resulting faint yellow opalescent solution was filtered through syringe microfilter (PTFE). The filtrate was evaporated to dryness and further co-evaporated with DCM (as a suspension). Residue was dissolved in a mixture of H₂O (300 mL) and DCM (300 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (8×75 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The resulting crystalized residue was crushed and further dried on high vacuum overnight to give product in the form of free base as nearly colorless solid. Yield: 2.29 g (97%; 1 step; based on TD549). NMR (DMSO-d₆): ¹H δ_H 4.59 (CH₂, s, 4H); 5.45 (OH, s, 2H); 7.45-7.57 (Ph, m, 3H); 7.60 (arom., s, 2H); 7.68-7.82 (Ph, m, 2H). ¹³C{¹H} δ_C 64.2 (CH₂, s); 115.7 (arom., s); 126.7 (Ph, s); 129.1 (Ph, s); 129.3 (Ph, s); 138.1 (Ph, s); 148.2 (arom., s); 161.7 (arom., s). ESI-HRMS: 216.1022 [M+H]⁺ (theor. [C₁₃H₁₄N₁O₂]⁺=216.1019).

Synthesis of TD564: In a round-bottom glass flask (500 mL), TD563 (2.25 g; 10.5 mmol; 1.0 equiv.) was dissolved (with gentle heating) in DCM (250 mL). Freshly prepared solution of SOCl₂ (2.27 mL; 31.3 mmol; 3.0 equiv.) in DCM (10 mL) was then added, after which precipitate started to form. After 1 h of stirring at RT, all of the previously formed precipitate was dissolved again. Dil. aq. solution of NaHCO₃ (150 mL) was then added to the clear yellow solution and the resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×100 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as faint yellow solid. Yield: 2.59 g (98%; 1 step; based on TD563). NMR (DMSO-d₆): ¹H δ_H 4.88 (CH₂, s, 4H); 7.47-7.58 (Ph, m, 3H); 7.77-7.85 (Ph, m, 2H); 7.86 (arom., s, 2H). ¹³C{¹H} δ_C 46.6 (CH₂, s); 120.3 (arom., s); 126.9 (Ph, s); 129.3 (Ph, s); 129.7 (Ph, s); 136.5 (Ph, s); 149.5 (arom., s); 157.1 (arom., s); 157.1 (arom., s); ESI-HRMS: 252.0342 [M+H]⁺ (theor. [C₁₃H₁₂N₁Cl₂]⁺=252.0341).

Synthesis of TD566: In a pear-shaped glass flask (100 mL), TD564 (1.60 g; 6.35 mmol; 1.3 equiv.) was

dissolved (with gentle heating) in MeCN (60 mL) followed by addition of solid NaN₃ (320 mg; 4.92 mmol; 1.0 equiv.) and dried K₂CO₃ (680 mg; 4.93 mmol; 1.0 equiv.) and the resulting suspension was stirred 24 h at 80° C. The mixture was filtered on glass frit S₃ and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and the orange oily residue was purified by column chromatography (SiO₂, 15% P.E. in DCM to 100% DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried 1 h on high vacuum to give product in the form of free base as white solid. Yield: 691 mg (54%; 1 step; based on NaN₃). Recovery: 613 mg of TD564 (38% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 4.59 (CH₂, s, 2H); 4.84 (CH₂, s, 2H); 7.46-7.60 (Ph, m, 3H); 7.74 (arom., d, 1H, ⁴J_HH=2); 7.77-7.85 (Ph, m, 2H); 7.86 (arom., d, 1H, ⁴J_HH=2). ¹³C{¹H} δ_C 46.7 (CH₂, s); 54.2 (CH₂, s); 119.4 (arom., s); 120.0 (arom., s); 126.9 (Ph, s); 129.3 (Ph, s); 129.7 (Ph, s); 136.6 (Ph, s); 149.3 (arom., s); 156.6 (arom., s); 157.1 (arom., s). ESI-HRMS: 259.0747 [M+H]⁺ (theor. [C₁₃H₁₂N₄Cl₁]⁺=259.0745).

Synthesis of TD1083: In a round-bottom glass flask (100 mL), methyl isonicotinate (250 mg; 1.83 mmol; 1.0 equiv.) was dissolved in MeOH (10 mL) followed by addition of conc. H₂SO₄ (25 μL). The resulting mixture was stirred 30 min at 55° C. After cooling down, solution of (NH₄)₂S₂O₅(4.16 g; 18.2 mmol; 10 equiv.) in H₂O (10 mL) was added dropwise and the resulting mixture was then further stirred 16 h at 55° C. Reaction was then carefully quenched by aq. NaHCO₃. Mixture was then transferred to a separatory funnel and extracted with EtOAc (5×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of free base as white fluffy solid. Yield: 99.5 mg (28%; 1 step; based on methyl isonicotinate). NMR (DMSO-d₆): ¹H δ_H 3.92 (CH₃, s, 3H); 4.60 (CH₂, d, 4H, ³J_HH=6); 5.58 (OH, t, 2H, ³J_HH=6); 7.80 (arom., s, 2H). ESI- HRMS: 198.0759 [M+H]⁺ (theor. [C₉H₁₂N₁O₄]⁺=198.0761). EA (C₉H₁₁N₁O₄, M_R=197.2): C 54.8 (54.8); H 5.6 (5.5); N 7.1 (7.0).

Synthesis of TD1087: In a round-bottom glass flask (50 mL), TD1083 (96.2 mg; 488 μmol; 1.0 equiv.) was dissolved in DCM (20 mL) followed by addition of SOCl₂ (106 μL; 1.46 mmol; 3.0 equiv.). The mixture was stirred 1 h at RT. Mixture was then quenched by addition of dil. aq. solution of NaHCO₃ (20 mL). The resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight (where product slowly crystallized) to give product in the form of free base as bright yellow solid. Yield: 112.8 mg (99%; 1 step; based on TD1083). NMR (DMSO-d₆): ¹H δ_H 3.92 (CH₃, s, 3H); 4.90 (CH₂, s, 4H); 7.98 (arom., s, 2H). ESI-HRMS: 234.0085 [M+H]⁺ (theor. [C₉H₁₀N₁O₂Cl₂]⁺=234.0083).

Synthesis of TD1089: In a glass vial (4 mL), TD1087 (112.0 mg; 478 μmol; 1.2 equiv.) was dissolved in MeCN (2 mL) followed by addition of solid NaN₃ (26.0 mg; 400 μmol; 1.0 equiv.) and dried K₂CO₃ (55.0 mg; 400 μmol; 1.0 equiv.) and the resulting suspension was stirred 2 h at 70° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and oily residue was purified by column chromatography (SiO₂, DCM to 10% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give pre-purified product (containing ˜20% of bis azide byproduct) in the form of free base as yellow oil. Yield: 49.6 mg. ESI-HRMS: 241.0490 [M+H]⁺ (theor. [C₉H₁₀N₄O₂Cl₁]⁺=241.0487). Part of TD1089 obtained in this way was directly used for TD1092 without further purification or characterization.

Synthesis of TD1101: In a round-bottom glass flask (100 mL), isopropyl isonicotinate (600 mg; 3.63 mmol; 1.0 equiv.) was dissolved in MeOH (20 mL) followed by addition of conc. H₂SO₄ (50 μL). Then, solution of (NH₄)₂S₂O₈(8.32 g; 36.5 mmol; 10 equiv.) in H₂O (20 mL) was added dropwise and the resulting mixture was further stirred 16 h at 70° C. Reaction was then carefully neutralized by aq. NaHCO₃. Mixture was then transferred to a separatory funnel and extracted with EtOAc (5×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of free base as white fluffy solid. Yield: 284 mg (35%; 1 step; based on isopropyl isonicotinate). NMR (DMSO-d₆): ¹H δ_H 1.34 (CH₃, d, 6H, ³J_HH=6); 4.59 (CH₂, d, 4H, ³J_HH=6); 5.19 (CH, hept, 1H, ³J_HH=6); 5.57 (OH, t, 2H, ³J_HH=6); 7.78 (arom., s, 2H). ESI-HRMS: 226.1076 [M+H]⁺ (theor. [C₁₁H₁₆N₁O₄]⁺=226.1074).

Synthesis of TD1109: In a round-bottom glass flask (100 mL), TD1101 (283 mg; 1.26 mmol; 1.0 equiv.) was dissolved in DCM (40 mL) followed by addition of SOCl₂ (275 μL; 3.79 mmol; 3.0 equiv.). The mixture was stirred 1 h at RT. Mixture was then quenched by addition of dil. aq. solution of NaHCO₃ (40 mL). The resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight (where product slowly crystallized) to give product in the form of free base as pale yellow solid. Yield: 322 mg (98%; 1 step; based on TD1101). NMR (DMSO-d₆): ¹H δ_H 1.35 (CH₃, d, 6H, ³J_HH=6); 4.90 (CH₂, s, 4H); 5.20 (CH, hept, 1H, ³J_HH=6); 7.96 (arom., s, 2H). ESI-HRMS: 262.0399 [M+H]⁺ (theor. [C₁₁H₁₄N₁O₂Cl₂]⁺=262.0396).

Synthesis of TD1112: In a glass vial (20 mL), TD1109 (321 mg; 1.23 mmol; 1.2 equiv.) was dissolved in MeCN (6 mL) followed by addition of solid NaN₃ (66.5 mg; 1.02 mmol; 1.0 equiv.) and dried K₂CO₃ (141 mg; 1.02 mmol; 1.0 equiv.) and the resulting suspension was stirred 16 h at 70° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and oily residue was purified by column chromatography (SiO₂, DCM to 3% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 116 mg (42%; 1 step; based on NaN₃). Recovery: 124 mg of TD1109 (39% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 1.35 (CH₃, d, 6H, ³J_HH=6); 4.67 (CH₂, s, 2H); 4.89 (CH₂, s, 4H); 5.19 (CH, hept, 1H, ³J_HH=6); 7.83 (arom., d, 1H, ⁴J_HH=1).7.95 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 269.0800 [M+H]⁺ (theor. [C₁₁H₁₄N₄O₂C₁]⁺=269.0800).

Synthesis of TD1119: In a glass vial (40 mL), tert-butyl isonicotinate (486 mg; 2.71 mmol; 1.0 equiv.) was dissolved in MeOH (15 mL) followed by addition of conc. H₂SO₄ (40 μL). Then, solution of (NH₄)₂S₂O₈(6.20 g; 27.2 mmol; 10 equiv.) in H₂O (15 mL) was added dropwise and the resulting mixture was further stirred 30 min at 80° C. Reaction was then carefully neutralized by aq. NaHCO₃. Mixture was then transferred to a separatory funnel and extracted with EtOAc (5×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of free base as white fluffy solid. Yield: 161 mg (25%; 1 step; based on tert-butyl isonicotinate). NMR (DMSO-d₆): ¹H δ_H 1.57 (CH₃, s, 9H); 4.58 (CH₂, d, 4H, ³J_HH=4); 5.54 (OH, t, 2H, ³J_HH=4); 7.73 (arom., s, 2H). ESI-HRMS: 240.1230 [M+H]⁺ (theor. [C₁₂H₁₈N₁O₄]⁺=240.1230).

Synthesis of TD1129: In a round-bottom glass flask (100 mL), TD1119 (159 mg; 664 μmol; 1.0 equiv.) was dissolved in DCM (20 mL) followed by addition of SOCl₂ (145 μL; 2.00 mmol; 3.0 equiv.). The mixture was stirred 1 h at RT. Mixture was then quenched by addition of dil. aq. solution of NaHCO₃ (20 mL). The resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight (where product slowly crystallized) to give product in the form of free base as faint yellow solid. Yield: 175 mg (95%; 1 step; based on TD1119). NMR (DMSO-d₆): ¹H δ_H 1.57 (CH₃, s, 9H); 4.89 (CH₂, s, 4H); 7.91 (arom., s, 2H). ESI-HRMS: 276.0552 [M+H]⁺ (theor. [C₁₂H₁₆N₁O₂Cl₂]⁺=276.0553).

Synthesis of TD1130: In a glass vial (4 mL), TD1129 (174.0 mg; 630 μmol; 1.2 equiv.) was dissolved in MeCN (3 mL) followed by addition of solid NaN₃ (34.0 mg; 523 μmol; 1.0 equiv.) and dried K₂CO₃ (72.0 mg; 522 μmol; 1.0 equiv.) and the resulting suspension was stirred 6 h at 70° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and oily residue was purified by column chromatography (SiO₂, DCM to 3% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 58.2 mg (39%; 1 step; based on NaN₃). Recovery: 90.5 mg of TD1129 (52% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 1.57 (CH₃, s, 9H); 4.66 (CH₂, s, 2H); 4.89 (CH₂, s, 2H); 7.79 (arom., d, 1H, ⁴J_HH=2). 7.91 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 305.0772 [M+Na]⁺ (theor. [C₁₂H₁₅N₄O₂Cl₁Na₁]⁺=305.0776).

Synthesis of TD725: Glass vial (40 mL) was charged with TD726 (628 mg; 3.62 mmol; 1.0 equiv.), (4-(tert-Butoxycarbonyl)phenyl)boronic acid (880 mg; 3.96 mmol; 1.1 equiv.) and XPhos Pd G2 (57 mg; 7.2 μmol; 2.0 mol %) and was then three times secured with argon. Under constant flow of argon was then added dry 1,4-Dioxane (16 mL) through septum followed by addition of freshly prepared (and briefly washed with argon prior addition) solution of K₃PO₄·H₂O (920 mg; 4.00 mmol; 1.1 equiv.) in H₂O (8 mL). The mixture was then stirred 16 h under septum (but without external argon) at 80° C. Resulting dark mixture was transferred to a separatory funnel and diluted with EtOAc (40 mL) and H₂O (50 ml). After shaking, upper layer was separated and aqueous layer was further extracted with EtOAc (5×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified on flash chromatography (120 g SiO₂, 100% EtOAc to 30% MeOH in EtOAc). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give pre-purified product in the form of free base as off-white powder. Yield: 1.04 g. NMR (DMSO-d₆): ¹H δ_H 1.57 (CH₃, s, 9H); 4.61 (CH₂, d, 4H, ³J_HH=6); 5.48 (OH, t, 2H, ³J_HH=6); 7.64 (arom., s, 2H); 7.88 (arom., dm, 2H, ³J_HH=9); 8.04 (arom., dm, 2H, ³J_HH=9). ¹³C{¹H} δ_C 27.8 (CH₃, s); 64.2 (CH₂, s); 81.0 (C—CH₃, s); 115.8 (arom., s); 127.0 (arom., s); 129.9 (arom., s); 131.6 (arom., s); 142.2 (arom., s); 147.0 (arom., s); 162.0 (arom., s); 164.6 (CO, s). ESI-HRMS: 316.1539 [M+H]⁺ (theor. [C₁₈H₂₂N₁O₄]⁺=316.1543).

Synthesis of TD730: In a round-bottom glass flask (250 mL), pre-purified TD725 (1.04 g; ≤3.30 mmol; 1.0 equiv.) was suspended in DCM (35 mL). Freshly prepared solution of SOCl₂ (721 μL; 9.93 mmol; ≥3.0 equiv.) in DCM (5 mL) was then added. Clear solution was quickly formed and the open flask was stirred 1 h at RT. Mixture was then quenched by addition of dil. aq. solution of NaHCO₃ (60 mL). The resulting biphasic mixture was vigorously stirred for additional 1 h at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (5×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was purified on flash chromatography (120 g SiO₂, 100% DCM to 20% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residual faint yellow oil slowly crystallized. The solid was crushed and further dried on high vacuum overnight to give product in the form of free base as off-white powder. Yield: 839 mg (66%; 2 steps; based on TD726). NMR (DMSO-d₆): ¹H δ_H 1.58 (CH₃, s, 9H); 4.86 (CH₂, s, 4H); 7.92 (arom., s, 2H); 7.94 (arom., dm, 2H, ³J_HH=9); 8.05 (arom., dm, 2H, ³J_HH=9). ¹³C{¹H} δ_C 27.8 (CH₃, s); 46.5 (CH₂, s); 81.2 (C—CH₃, s); 120.6 (arom., s); 127.2 (arom., s); 129.9 (arom., s); 132.1 (arom., s); 140.6 (arom., s); 148.3 (arom., s); 157.3 (arom., s); 164.5 (CO, s). ESI-HRMS: 352.0866 [M+H]⁺ (theor. [C₁₈H₂₀N₁O₂Cl₂]⁺=352.0866).

Synthesis of TD733: In a glass vial (20 mL), TD730 (837 mg; 2.38 mmol; 1.3 equiv.) was dissolved in MeCN (18 mL) followed by addition of solid NaN₃ (119 mg; 1.83 mmol; 1.0 equiv.) and dried K₂CO₃ (253 mg; 1.83 mmol; 1.0 equiv.) and the resulting suspension was stirred 24 h at 80° C. The mixture was filtered on through syringe microfilter (PTFE) and the solid residue was washed with MeCN. Filtrate was evaporated to dryness and oily residue was purified by column chromatography (SiO₂, 20% Pentane in DCM to 1% EtOAc in DCM). Fractions with product were combined and evaporated to dryness. The resulting nearly colorless oil was further dried on high vacuum overnight (where product slowly crystallized) to give product in the form of free base as colorless solid. Yield: 230 mg (35%; 1 step; based on NaN₃). Recovery: 442 mg of TD730 (53% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 1.57 (CH₃, s, 9H); 4.62 (CH₂, s, 2H); 4.86 (CH₂, s, 2H); 7.80 (arom., d, 1H, ⁴J_HH=2); 7.91 (arom., d, 1H, ⁴J_HH=2); 7.94 (arom., dm, 2H, ³J_HH=9); 8.05 (arom., dm, 2H, ³J_HH=9). ¹³C{¹H} δ_C 27.8 (CH₃, s); 46.6 (CH₂, s); 54.2 (CH₂, s); 81.2 (C—CH₃, s); 119.6 (arom., s); 120.3 (arom., s); 127.2 (arom., s); 129.9 (arom., s); 132.1 (arom., s); 140.7 (arom., s); 148.1 (arom., s); 156.8 (arom., s); 157.3 (arom., s); 164.5 (CO, s). ESI-HRMS: 359.1270 [M+H]⁺ (theor. [C₁₈H₂₀N₄O₂Cl₁]⁺=359.1269).

Synthesis of TD1425: Glass vial (40 mL) was charged methyl 2-bromo-6-methylisonicotinate (1.00 g; 4.35 mmol; 1.0 equiv.), NBS (recrystallized from boiling H₂O; 770 mg; 4.33 mmol; 1.0 equiv.), (BnO)₂ (53 mg; 219 μmol; 5 mol %) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added CCl₄ (21 mL) through septum. The vial was left stirring under septum (but without external argon) for 24 h at 75° C. After cooling down, the mixture was filtered through syringe microfilter (PTFE) and the solids were washed with DCM. Filtrate was evaporated to dryness, re-suspended in c-Hex (25 ml) and filtered through syringe microfilter (PTFE). Filtrate was evaporated to dryness and the residue was purified by flash chromatography (120 g SiO₂, 100% c-Hex to 80% DCM in c-Hex). Combined fractions with product were evaporated to dryness. The residual oil was further dried on high vacuum overnight (where the product crystallized) to give product in the form of free base as faint yellow solid. Yield: 571 mg (43%; 1 step; based on methyl 2-bromo-6-methylisonicotinate). Recovery: 314 mg of methyl 2-bromo-6-methylisonicotinate (31% of the initial amount used). NMR (DMSO-d₆): ¹H δ_H 3.91 (CH₃, s, 3H); 4.79 (CH₂, s, 2H); 7.94 (arom., d, 1H, ⁴J_HH=1); 8.05 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 307.8916 [M+H]⁺ (theor. [C₈H₈N₁O₂Br₂]⁺=307.8916).

Synthesis of TD1428: Pear-shaped glass flask (25 mL) was charged with TD1425 (523 mg; 1.69 mmol; 1.0 equiv.), N-Boc-1,1-dimethylpropargylamine (310 mg; 1.69 mmol; 1.0 equiv.) and magnetic stirrer and three times secured with argon. Solid CuI (13.0 mg; 68 μmol; 4.0 mol %) and [Pd(PPh₃)₂Cl₂](24 mg; 34 μmol; 2.0 mol %) were subsequently added followed by another securing with argon (three times). Under constant flow of argon was then added dry THF (7.5 mL) through septum followed by addition of DIPEA (885 μL; 5.08 mmol; 3.0 equiv.). The flask was left stirring under septum (but without external argon) for 2 d at RT. The mixture was evaporated to dryness, re-suspended in DCM (15 mL) and filtered through syringe microfilter (PTFE) and the solid phase was further washed with DCM. Filtrate was purified on flash chromatography (120 g SiO₂, 10% EtOAc in c-Hex to 50% EtOAc in c-Hex). Combined fractions with product were evaporated to dryness and once re-purified on flash chromatography (80 g SiO₂, 100% DCM to 5% EtOAc in DCM). Combined fractions with product were evaporated to dryness and further co-evaporated once with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as faint yellow solidified oil. Yield: 175 mg (25%; 1 step; based on TD1425). NMR (DMSO-d₆): ¹H δ_H 1.42 (CH₃—C—O, s, 9H); 1.56 (CH₃—C—N, s, 6H); 3.91 (CH₃—O, s, 3H); 4.79 (CH₂, s, 2H); 7.23 (NH, bs, 1H); 7.71 (arom., d, 1H, ⁴J_HH=1); 7.97 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 411.0913 [M+H]⁺ (theor. [C₁₈H₂₄N₂O₄Br₁]⁺=411.0914).

Synthesis of TD1386: In a round-bottom glass flask (100 mL), pyridine-2,6-diyldimethanol (2.00 g; 14.4 mmol; 1.0 equiv.) and Imidazole (0.98 g; 14.4 mmol; 1.0 equiv.) were dissolved in DMF (20 mL) followed by addition of TBDMSCl (2.17 g; 14.4 mmol; 1.0 equiv.). The resulting solution was stirred 2 h at RT. Mixture was evaporated to dryness and the residue dissolved in a mixture of DCM (50 mL) and dil. aq. NaHCO₃ (50 mL) and transferred to a separatory funnel. After brief shaking, the bottom phase was separated and the aq. layer was further extracted with DCM (5×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was purified by column chromatography (100 g SiO₂, DCM to 50% EtOAc in DCM). Fractions with product were combined and evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 1.54 g (42%; 1 step; based on pyridine-2,6-diyldimethanol). NMR (DMSO-d₆): ¹H δ_H 0.09 (CH₃, s, 6H); 0.92 (CH₃, s, 9H); 4.51 (CH₂, d, 2H, ³J_HH=5); 4.71 (CH₂, s, 2H); 5.37 (OH, t, 1H, ³J_HH=5); 7.28 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.34 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.81 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 254.1569 [M+H]⁺ (theor. [C₁₃H₂₄N₁O₂Si₁]⁺=254.1571).

Synthesis of TD1389: In a round-bottom glass flask (250 mL), TD1386 (1.54 g; 6.08 mmol; 1.0 equiv.) was dissolved in DCM (60 mL) followed by addition of SOCl₂ (885 μL; 12.0 mmol; 2.0 equiv.). The mixture was stirred 1 h at RT. Mixture was then quenched by addition of dil. aq. solution of NaHCO₃ (60 mL). The resulting biphasic mixture was vigorously stirred for additional 30 min at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 1.63 g (99%; 1 step; based on TD1386). NMR (DMSO-d₆): ¹H δ_H 0.10 (CH₃, s, 6H); 0.92 (CH₃, s, 9H); 4.74 (CH₂, s, 2H); 4.75 (CH₂, s, 2H); 7.40 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.42 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.87 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 272.1231 [M+H]⁺ (theor. [C₁₃H₂₃N₁O₁Cl₁Si₁]⁺=272.1232).

Synthesis of TD1390: In a glass flask (20 mL), KCN (390 mg; 5.99 mmol; 1.05 equiv.) was dissolved in H₂O (2 mL) followed by addition of TD1389 (1.55 g; 5.70 mmol; 1.0 equiv.) in DMF (6 mL). The resulting mixture was vigorously stirred for 70 min at 100° C. After cooling to RT, mixture was diluted with H₂O (4 mL) and MeCN (8 mL) and filtered through syringe microfilter (PTFE). Filtrate was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residual pale yellow oil was left in a freezer to solidify. Resulting solid was crushed and further dried on high vacuum overnight to give product in the form of free base as faint yellow powder. Yield: 1.23 g (82%; 1 step; based on TD1389). NMR (DMSO-d₆): ¹H δ_H 0.10 (CH₃, s, 6H); 0.92 (CH₃, s, 9H); 4.17 (CH₂, s, 2H); 4.75 (CH₂, s, 2H); 7.30 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.40 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.86 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 263.1573 [M+H]⁺ (theor. [C₁₄H₂₃N₂O₁Si₁]⁺=263.1574).

Synthesis of TD1393: In a pear-shaped glass flask (100 mL), TD1390 (700 mg; 2.67 mmol; 1.00 equiv.) was dissolved in MeOH (2.70 mL; 66.7 mmol; 25 equiv.) followed by addition of TMSCl (2.37 mL; 18.7 mmol; 7.0 equiv.). The resulting mixture was vigorously stirred for 2 h at 60° C. After cooling to RT, mixture was quenched with H₂O (4 mL) and partly neutralized (to pH 3-4) by slow addition of sat. aq. NaHCO₃ (5 mL). Resulting biphasic mixture was carefully evaporated to dryness followed by addition of H₂O (10 mL) to the residue. Mixture was then filtered through syringe microfilter (RC) and the filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as faint yellow oil. Yield: 404 mg (84%; 1 step; based on TD1390). NMR (DMSO-d₆): ¹H δ_H 3.61 (CH₃, s, 3H); 3.81 (CH₂, s, 2H); 4.51 (CH₂, d, 2H, ³J_HH=5); 5.39 (OH, t, 1H, ³J_HH=5); 7.20 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.36 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.76 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 182.0811 [M+H]⁺ (theor. [C₉H₁₂N₁O₃]⁺=182.0812).

Synthesis of TD1395: In a round-bottom glass flask (50 mL), TD1393 (340 mg; 1.88 mmol; 1.0 equiv.) and Imidazole (190 mg; 2.79 mmol; 1.5 equiv.) were dissolved in DMF (6 mL) followed by addition of TBDMSCl (425 mg; 2.82 mmol; 1.5 equiv.). The resulting solution was stirred 16 h at RT. Mixture was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as faint yellow oil. Yield: 537 mg (97%; 1 step; based on TD1393). NMR (DMSO-d₆): ¹H δ_H 0.09 (CH₃, s, 6H); 0.91 (CH₃, s, 9H); 3.61 (CH₃, s, 3H); 3.81 (CH₂, s, 2H); 4.70 (CH₂, s, 2H); 7.23 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.32 (arom., dd, 1H, ³J_HH8=8; ⁴J_HH=1); 7.79 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 296.1676 [M+H]⁺ (theor. [C₁₅H₂₆N₁O₃Si₁]⁺=296.1677).

Synthesis of TD1396: In a round-bottom glass flask (100 mL), TD1395 (537 mg; 1.82 mmol; 1.0 equiv.) was dissolved in a mixture of THF (9 mL) and MeOH (9 mL). To the resulting colourless solution was added portion wise (over course of 10 min, with no stopper on the flask) solid NaBH₄ (2.06 g; 54.5 mmol; 30 equiv.) during which hydrogen gas evolved intensively. Mixture was further stirred 1 h at RT, during which was twice diluted with MeOH (9 mL each) to ensure stirring. Mixture was then diluted with DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colourless oil. Yield: 483 mg (99%; 1 step; based on TD1395). NMR (DMSO-d₆): ¹H δ_H 0.09 (CH₃, s, 6H); 0.92 (CH₃, s, 9H); 2.84 (CH₂, t, 2H, ³J_HH=7); 3.71 (CH₂, td, 2H, ³J_HH=7, ³J_HH=5); 4.62 (OH, t, 1H, ³J_HH=5); 4.71 (CH₂, s, 2H); 7.14 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.24 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.70 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 268.1726 [M+H]⁺ (theor. [C₁₄H₂₆N₁O₂Si₁]⁺=268.1727).

Synthesis of TD1401: In a round-bottom glass flask (50 mL), TD1396 (94 mg; 352 μmol; 1.0 equiv.) was dissolved in DCM (3.5 mL) followed by addition of SOCl₂ (51 μL; 702 μmol; 2.0 equiv.). The mixture was stirred 3 h at RT. Mixture was then diluted with DCM (20 mL) and quenched by addition of dil. aq. solution of NaHCO₃ (10 mL). The resulting biphasic mixture was vigorously stirred for additional 30 min at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×15 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was dissolved in DMF (1.7 mL) followed by addition of solid NaN₃ (46 mg; 708 μmol; 2.0 equiv.). The resulting mixture was stirred at 80° C. overnight. After cooling, the mixture was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil. Yield: 17.6 mg (28%; 2 steps; based on TD1396). NMR (DMSO-d₆): ¹H δ_H 2.98 (CH₂, t, 2H, ³J_HH=7); 3.69 (CH₂, td, 2H, ³J_HH=7, ³J_HH=5); 4.53 (CH₂, d, 2H, ³J_HH=6); 5.37 (OH, t, 1H, ³J_HH=6); 7.18 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.32 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.73 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 201.0746 [M+Na]⁺ (theor. [C₈H₁₀N₄O₁Na₁]⁺=201.0747).

Synthesis of TD1406: In a round-bottom glass flask (25 mL), TD1401 (16.5 mg; 92.6 μmol; 1.0 equiv.) was dissolved in DCM (1.85 mL) followed by addition of SOCl₂ (13.5 μL; 186 μmol; 2.0 equiv.). The mixture was stirred 1 h at RT. Mixture was then diluted with DCM (10 mL) and quenched by addition of dil. aq. solution of NaHCO₃ (10 mL). The resulting biphasic mixture was vigorously stirred for additional 30 min at RT, during which bubbles of gas slowly evolved. Mixture was then transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless solid. Yield: 17.7 mg (97%; 1 step; based on TD1401). NMR (DMSO-d₆): ¹H δ_H 3.02 (CH₂, t, 2H, ³J_HH=7); 3.71 (CH₂, td, 2H, ³J_HH=7, ³J_HH=5); 4.75 (CH₂, s, 2H); 7.32 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.41 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.79 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 197.0589 [M+H]⁺ (theor. [C₈H₁₀N₄Cl₁]⁺=197.0589).

Synthesis of TD1339: Pear-shaped glass flask (250 mL) was charged with ethyl 1-lactate (3.54 g; 30.0 mmol; 1.00 equiv.) and magnetic stirrer and three times briefly secured with argon. Under constant flow of argon was then added dry DCM (100 mL) through septum and the mixture was cooled with an ice bath (5° C.) followed by dropwise addition of triflic anhydride (5.3 mL; 31.5 mmol; 1.05 equiv.) and immediately followed by dropwise addition of dry pyridine (2.54 ml; 31.5 mmol; 1.05 equiv.). The resulting mixture was stirred at 5° C. for 30 min. Resulting suspension was then directly purified by column chromatography (140 g SiO₂, DCM). Combined fractions with product were evaporated to dryness and briefly dried on high vacuum to give product as faintly pinkish oil. Yield: 5.90 g (79%; 1 step; based on ethyl 1-lactate). NMR (DMSO-d₆): ¹H δ_H 1.26 (CH₃—CH₂, t, 3H, ³J_HH=7); 1.51 (CH₃—CH, d, 3H, ³J_HH=7); 4.19-4.31 (CH₂, m, 2H); 5.27 (CH, q, 1H, ³J_HH=7). ¹⁹F{¹H}δ_F −77.7 (s). CI-HRMS: 251.0193 [M+H]⁺ (theor. [C₆H₁₀O₅S₁F₃]⁺=251.0196).

Synthesis of TD1488: Pear-shaped glass flask (25 mL) was charged with dimethyl L-malate (200 mg; 1.23 mmol; 1.00 equiv.) and magnetic stirrer and three times briefly secured with argon. Under constant flow of argon was then added dry DCM (4 mL) through septum and the mixture was cooled with an ice bath (5° C.) followed by dropwise addition of triflic anhydride (220 μL; 1.31 mmol; 1.06 equiv.) and immediately followed by dropwise addition of dry pyridine (105 μL; 1.30 mmol; 1.06 equiv.). The resulting mixture was stirred at RT for 30 min. Resulting suspension was then directly purified by column chromatography (30 g SiO₂, DCM). Combined fractions with product were evaporated to dryness and briefly dried on high vacuum to give product as colourless oil. Yield: 258 mg (77%; 1 step; based on dimethyl L-malate). NMR (DMSO-d₆): ¹H δ_H 3.08 (CH₂, dd, 1H, ²J_HH=17, ³J_HH=5); 3.13 (CH₂, dd, 1H, ²J_HH=17, ³J_HH=6); 4.65 (CH₃, s, 3H); 3.78 (CH₃, s, 3H); 5.48 (CH, dd, 1H, ³J_HH=6, ³J_HH=5). ¹⁹F{¹H} δ_F −77.7 (s). ESI-HRMS: 316.9910 [M+Na]⁺ (theor. [C₇H₉O₇F₃S₁Na₁]⁺=316.9913).

Example 3: Synthesis of Protected Macrocyclic Intermediates

Synthesis of TD680: In a pear-shape glass flask (250 mL), Cbz2cyclen (free base; 1.54 g; 3.50 mmol; 1.6 equiv.) was dissolved in MeCN (100 mL) followed by addition of dried K₂CO₃ (300 mg; 2.17 mmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of tert-Butyl bromoacetate (427 mg; 2.19 mmol; 1.0 equiv.) in dry MeCN (25 mL) was added dropwise (over the course of 2 h). Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (150 mL) and H₂O (150 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×75 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 624 mg (51%; 1 step; based on tert-Butyl bromoacetate). NMR (CD₃CN): ¹H δ_H 1.32-1.49 (CH₃, m, 9H); 2.57-2.76 (mc, m, 4H); 2.81-2.98 (mc, m, 4H); 3.23-3.64 (mc, CH₂—CO, m, 8+2H); 5.00-5.15 (CH₂-Ph, m, 4H); 7.19-7.48 (Ph, m, 10H). ESI-HRMS: 555.3171 [M+H]⁺ (theor. [C₃₀H₄₃N₄O₆]⁺=555.3177).

Synthesis of TD686: In a glass vial (4 mL), TD680 (150 mg; 270 μmol; 1.0 equiv.) was dissolved in MeCN (3 mL) followed by addition of Boc₂O (2.0 M solution in THF; 200 μL; 400 μmol; 1.5 equiv.). Resulting mixture was stirred 16 h at RT. Reaction mixture was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, immediately neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil. Yield: 170 mg (96%; 1 step; based on TD680). NMR (CD₃CN): ¹H δ_H 1.17-1.56 (CH₃, m, 18H); 2.62-2.99 (mc, m, 4H); 3.10-3.53 (mc, CH₂—CO, m, 12+2H); 4.96-5.16 (CH₂-Ph, m, 4H); 7.20-7.47 (Ph, m, 10H). ESI-HRMS: 655.3691 [M+H]⁺ (theor. [C₃₅H₅₁N₄O₈]⁺=655.3701).

Synthesis of TD691: Pear-shape glass flask (25 mL) was charged with TD686 (170 mg; 260 μmol) and magnetic stirrer and three times secured with argon. Solid Pd@C (17 mg) was then added followed by another securing with argon (three times). Under constant flow of argon was then added MeOH (10 mL) through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 30 min at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil. Yield: 100 mg (≥99%; 1 step; based on TD686). ESI-MS (LC-MS): 387.3 [M+H]⁺ (theor. [C₁₉H₃₉N₄O₄]⁺=387.3). All of TD691 was directly used for TD692 without further characterization.

Synthesis of TD1106: In a pear-shape glass flask (50 mL), Cbz2cyclen (free base; 500 mg; 1.14 mmol; 1.0 equiv.) was dissolved in MeCN (10 mL) followed by addition of dried K₂CO₃ (870 mg; 5.69 mmol; 5.0 equiv.) and Methyl bromoacetate (235 μL; 2.51 mmol; 2.2 equiv.) in MeCN (5 mL). The resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil. Yield: 422 mg (64%; 1 step; based on Cbz2cyclen). NMR (CD₃CN): ¹H δ_H 2.63-2.88 (mc, m, 8H); 3.19-3.49 (mc, CH₂—CO, m, 8+4H); 3.59 (CH₃, s, 6H); 5.07 (CH₂-Ph, s, 4H); 7.21-7.41 (Ph, m, 10H). ESI-LCMS: 585.3 [M+H]⁺ (theor. [C₃₀H₄₁N₄O₈]⁺=585.3).

Synthesis of TD1116: Pear-shape glass flask (50 mL) was charged with Pd@C (42 mg) and magnetic stirrer and three times secured with argon. Under constant flow of argon was then added solution of TD1106 (418 mg; 715 μmol) in MeOH (25 mL) through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 1 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil that crystallized on standing. Yield: 223 mg (99%; 1 step; based on TD1106). NMR (CD₃CN): ¹H δ_H 2.48-2.57 (mc, m, 8H); 2.63-2.74 (mc, m, 8H); 3.36 (CH₂—CO, s, 4H); 3.64 (CH₃, s, 6H). ESI-MS (LC-MS): 317.2 [M+H]⁺ (theor. [C₁₄H₂₉N₄O₄]⁺=317.2).

Synthesis of TD687: In a glass vial (2 mL), TD680 (150 mg; 270 μmol; 1.0 equiv.) and P(OEt)₃ (232 μL; 1.35 mmol; 5.0 equiv.) were mixed together followed by addition of solid (CH₂O)_n (12 mg; 400 μmol; 1.5 equiv.). The resulting suspension was stirred 3 d at RT. Reaction mixture was then diluted with MeCN (700 μL) and filtered through syringe microfilter (PTFE). Filter was further washed with MeCN. Filtrate was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, immediately neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as slightly yellow oil. Yield: 167 mg (87%; 1 step; based on TD680). ESI-MS (LC-MS): 705.4 [M+H]⁺ (theor. [C₃₅H₅₄N₄O₉P₁]⁺=705.4). All of TD687 was directly used for TD695 without further characterization.

Synthesis of TD695: Pear-shape glass flask (25 mL) was charged with TD687 (167 mg; 237 μmol) and magnetic stirrer and three times secured with argon. Solid Pd@C (17 mg) was then added followed by another securing with argon (three times). Under constant flow of argon was then added MeOH (10 mL) through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 30 min at RT. The reaction mixture was further stirred under hydrogen atmosphere (from balloon) 16 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as slightly yellow oil. Yield: 100 mg (97%; 1 step; based on TD686). ESI-MS (LC-MS): 437.2 [M+H]⁺ (theor. [C₁₉H₄₁N₄O₅P₁]⁺=437.3). All of TD695 was directly used for TD700 without further characterization.

Synthesis of TD913: In a glass vial (20 mL), Cbz2cyclen (free base; 242 mg; 549 μmol; 1.0 equiv.) was dissolved in MeCN (12 mL) followed by addition of solid (CH₂O)_n (50 mg; 1.67 mmol; 3.0 equiv.) and PhP(OMe)₂ (350 μL; 2.2 mmol; 4.0 equiv.). The resulting suspension was stirred 24 h at 80° C. Reaction mixture was then filtered through syringe microfilter (PTFE) and the filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (75 mL) and H₂O (75 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colourless oil. Yield: 259 mg (61%; 1 step; based on Cbz2cyclen). NMR (CD₃CN): ¹H δ_H 2.30-3.38 (mc, CH₂—P, m, 16+4H); 3.47 (CH₃, d, 6H, ³J_HP=11); 5.00-5.12 (CH₂-Ph, m, 4H); 7.27-7.40 (Ph, m, 10H); 7.40-7.51 (Ph, m, 4H); 7.51-7.60 (Ph, m, 2H); 7.60-7.82 (Ph, m, 4H). ³¹P δ_P 42.8 (m). ESI-HRMS: 777.3178 [M+H]⁺ (theor. [C₄₀H₅₁N₄O₈P₂]⁺=777.3177).

Synthesis of TD910: Pear-shape glass flask (50 mL) was charged with TD913 (250 mg; 322 μmol) and magnetic stirrer and three times secured with argon. Solid Pd@C (50 mg) was then added followed by another securing with argon (three times). Under constant flow of argon was then added MeOH (25 mL) through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 2 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colourless oil. Yield: 161 mg (98%; 1 step; based on TD913). NMR (CD₃CN): ¹H δ_H 2.28-3.14 (mc, CH₂—P, m, 16+4H); 3.53 (CH₃, d, 3H, ³J_HP=11); 3.54 (CH₃, d, 3H, ³J_HP=11); 7.46-7.63 (Ph, m, 6H); 7.71-7.83 (Ph, m, 4H). ³¹P δ_P 43.3 (m). ESI-HRMS: 509.2438 [M+H]⁺ (theor. [C₂₄H₃₉N₄O₄P₂]⁺=509.2441).

Synthesis of TD571: In a glass vial (4 mL), Cbz2cyclen (free base; 1.00 g; 2.27 mmol; 1.0 equiv.) and P(OEt)₃ (2.00 mL; 11.7 mmol; 5.1 equiv.) were mixed together followed by addition of solid (CH₂O)_n (164 mg; 5.47 mmol; 2.4 equiv.). The resulting suspension was stirred 24 h at RT. Reaction mixture was then evaporated to dryness and the residue was purified by column chromatography (SiO₂; 80 g; DCM-MeOH-aq. NH₃ 150:10:1). Fractions with product were combined and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as slightly yellow oil. Yield: 1.29 g (77%; 1 step; based on Cbz2cyclen). ESI-MS (LC-MS): 741.3 [M+H]⁺ (theor. [C₃₄H₅₅N₄O₁₀P₂]⁺=741.3). All of TD571 was directly used for TD573 without further characterization.

Synthesis of TD573: Pear-shape glass flask (100 mL) was charged with TD571 (1.29 g; 1.74 mmol) and magnetic stirrer and three times secured with argon. Solid Pd@C (129 mg) was then added followed by another securing with argon (three times). Under constant flow of argon was then added EtOH (96%, 70 mL) through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 30 min at RT. The reaction mixture was further stirred under hydrogen atmosphere (from balloon) 16 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with EtOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as slightly yellow oil. Yield: 776 mg (95%; 1 step; based on TD571). ESI-MS (LC-MS): 473.2 [M+H]⁺ (theor. [C₁₈H₄₃N₄O₄P₂]⁺=473.3). Major portion of TD573 was directly used for TD579 without further characterization.

Synthesis of TD423: In a pear-shape glass flask (25 mL), tBuDO2A (free base; 410 mg; 1.03 mmol; 1.4 equiv.) was dissolved in dry MeCN (8 mL) followed by addition of Cs₂CO₃ (840 mg; 2.58 mmol; 3.4 equiv.) and of KI (172 mg; 1.04 mmol; 1.4 equiv.). Solution of 2-Chloro-N-(prop-2-yn-1-yl)acetamide (100 mg; 760 μmol; 1.0 equiv.) in dry MeCN (2 mL) was added and the resulting mixture was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness to give pre-purified product in the form of free base as yellow oil. Yield: 180 mg (˜75% of TD423 in a mixture with ˜25% of bis(substituted) by-product). ESI-MS (LC-MS): 496.4 [M+H]⁺ (theor. [C₂₅H₄₆N₅O₅]⁺=496.3). All of TD423 was directly used for TD425 without further purification and characterization.

Synthesis of TD635: In a pear-shape glass flask (250 mL), tBuDO2A (free base; 1.21 g; 3.02 mmol; 2.3 equiv.) was dissolved in MeCN (150 mL). To the vigorously stirred reaction mixture, solution of TD558 (1202 mg; 1.33 mmol; 1.0 equiv.) in MeCN (100 mL) was added dropwise (over the course of 2 h). Resulting mixture was further stirred 2 d at RT after which was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as faint yellow oil that crystallized on standing. Yield: 453 mg (66%; 1 step; based on TD558). NMR (CD₃CN): ¹H δ_H 1.39 (CH₃, s, 18H); 2.53 (mc, m, 4H); 2.61 (mc, m, 4H); 2.73 (mc, m, 4H); 2.77 (mc, m, 4H); 3.01 (CH₂—CO, s, 4H); 3.44 (C≡CH, s, 1H); 3.66 (CH₂-arom., s, 2H); 7.38 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.70 (arom., t, 1H, ³J_HH=8); 7.76 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1). ¹³C{¹H} δ_C 28.4 (CH₃, s); 48.2 (mc, s); 51.8 (mc, s); 52.6 (mc, s); 54.9 (mc, s); 57.6 (CH₂—CO, s); 59.3 (CH₂-arom., s); 78.0 (C≡CH, s); 81.3 (C—CH₃, s); 84.0 (C≡CH, s); 124.9 (arom., s); 126.5 (arom., s); 137.8 (arom., s); 141.6 (arom., s); 162.8 (arom., s); 172.0 (CO, s). ESI-HRMS: 516.3542 [M+H]⁺ (theor. [C₂₈H₄₆N₅O₄]⁺=516.3544).

Synthesis of TD539: In a pear-shape glass flask (100 mL), tBuDO2A (free base; 1.73 g; 4.32 mmol; ≥2.0 equiv.) was dissolved in dry MeCN (15 mL) followed by addition of dried K₂CO₃ (900 mg; 6.52 mmol; ≥3.0 equiv.). To the vigorously stirred reaction mixture, solution of freshly prepared and isolated TD538 (42.17 mmol; 1.0 equiv.) in dry MeCN (10 mL) was added dropwise (over the course of 15 min). Resulting mixture was further stirred 20 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (150 mL) and H₂O (150 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×100 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow solidified oil. Yield: 653 mg (47%; 2 steps; based on TD530). NMR (CD₃CN): ¹H δ_H 1.39 (CH₃, s, 18H); 1.43 (CH₃, s, 9H); 2.51-2.84 (mc, m, 16H); 3.01 (CH₂—CO, s, 4H); 3.64 (CH₂-arom., s, 2H); 4.05 (CH₂—C≡C, bd, 2H, ³J_HH=5); 5.97 (NH—CO, bt, 1H, ³J_HH=5); 7.27 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.66-7.75 (arom., m, 2H). ¹³C{¹H} δ_C 28.4 (CH₃, s); 28.6 (CH₃, s); 31.2 (CH₂—C≡C, bs); 48.1 (mc, s); 51.8 (mc, s); 52.8 (mc, s); 55.1 (mc, s); 57.6 (CH₂—CO, s); 59.6 (CH₂-arom., s); 81.3 (C—CH₃, 2×s); 82.6 and 87.0 (C≡C, 2×s); 124.3 (arom., s); 126.0 (arom., s); 137.7 (arom., s); 142.3 (arom., s); 162.7 (arom., s); 172.0 (CO, s). ESI-HRMS: 645.4331 [M+H]⁺ (theor. [C₃₄H₅₇N₆O₆]⁺=645.4334).

Synthesis of TD1118: In a pear-shape glass flask (50 mL), tBuDO2A (free base; 160 mg; 399 μmol; ≥2.5 equiv.) was dissolved in MeCN (10 mL) followed by addition of dried K₂CO₃ (65 mg; 470 μmol; ≥3 equiv.). To the vigorously stirred reaction mixture, solution of freshly prepared and isolated TD1117 (≤470 mmol; 1.0 equiv.) in MeCN (10 mL) was added dropwise (over the course of 5 min). Resulting mixture was further stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C₁₈; H₂O—MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated.

Aqueous phase was further extracted with DCM (3×30 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless solidified oil. Yield: 62.2 mg (57%; 2 steps; based on TD966). NMR (CD₃CN): ¹H δ_H 1.40 (CH₃, s, 18H); 1.43 (CH₃, s, 9H); 1.53-1.64 (CH₂, m, 2H); 1.82-1.91 (CH₂, m, 2H); 2.47-2.79 (mc, m, 16H); 2.79-2.88 (CH—C—C, m, 1H); 3.01 (CH₂—CO, s, 4H); 3.06-3.18 (CH₂, m, 2H); 3.63 (CH₂-arom., s, 2H); 3.71-3.82 (CH₂, m, 2H); 7.27 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.62-7.72 (arom., m, 2H). ESI-HRMS: 699.4801 [M+H]⁺ (theor. [C₃₈H₆₃N₆O₆]⁺=699.4804).

Synthesis of TD692: In a pear-shape glass flask (250 mL), TD681 (100 mg; 259 μmol; 1.5 equiv.) was dissolved in MeCN (25 mL). To the vigorously stirred reaction mixture, solution of TD558 (26 mg; 172 μmol; 1.0 equiv.) in MeCN (25 mL) was added dropwise (over the course of 1 h). Resulting mixture was further stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, immediately neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 38 mg (44%; 1 step; based on TD558). ESI-MS (LC-MS): 502.4 [M+H]⁺ (theor. [C₂₇H₄₄N₅O₄]⁺=502.3). All of TD692 was directly used for TD703 without further characterization.

Synthesis of TD700: In a pear-shape glass flask (100 mL), TD695 (100 mg; 229 μmol; 1.5 equiv.) was dissolved in MeCN (25 mL) followed by addition of dried K₂CO₃ (21 mg; 152 μmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of TD558 (23 mg; 152 μmol; 1.0 equiv.) in MeCN (25 mL) was added dropwise (over the course of 1 h). Resulting mixture was further stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (75 mL) and H₂O (75 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 20 mg (24%; 1 step; based on TD558). ESI-MS (LC-MS): 552.3 [M+H]⁺ (theor. [C₂₇H₄₇N₅O₅P₁]⁺=552.3). All of TD700 was directly used for TD705 without further characterization.

Synthesis of TD579: In a pear-shape glass flask (25 mL), TD573 (600 mg; 1.27 mmol; 2.0 equiv.) was dissolved in MeCN (10 mL). To the vigorously stirred reaction mixture, solution of TD558 (30 mg; 488 μmol; 1.0 equiv.) in MeCN (10 mL) was added dropwise (over the course of 30 min). Resulting mixture was further stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (125 mL), H₂O (125 mL) and aq. NaOH (1%; 20 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as yellow oil. Yield: 137 mg (48%; 1 step; based on TD558). ESI-MS (LC-MS): 588.3 [M+H]⁺ (theor. [C₂₆H₄₈N₅O₆P₂]⁺=588.3). TD579 was directly used for TD575 and TD580 and without further characterization.

Synthesis of TD799: In a pear-shape glass flask (100 mL), tBuDO2Prop (free base; 165 mg; 385 μmol; 2.0 equiv.) was dissolved in MeCN (30 mL). To the vigorously stirred reaction mixture, solution of TD558 (29 mg; 191 μmol; 1.0 equiv.) in MeCN (30 mL) was added dropwise (over the course of 6 h). Resulting mixture was further stirred 10 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as slightly yellow oil. Yield: 47 mg (45%; 1 step; based on TD558). NMR (CD₃CN): ¹H δ_H 1.38 (CH₃, s, 18H); 2.19-2.25 (CH₂—CO, m, 4H); 2.44-2.64 (mc, CH₂—CH₂—CO, m, 16+4H); 3.41 (C≡CH, s, 1H); 3.66 (CH₂-arom., s, 2H); 7.36 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.70 (arom., t, 1H, ³J_HH=8); 7.77 (arom., bd, 1H, ³J_HH=8). ESI-HRMS: 544.3854 [M+H]⁺ (theor. [C₃₀H₅₀N₅O₄]⁺=544.3857).

Synthesis of TD663: In a pear-shape glass flask (50 mL), tBuDO2A (free base; 210 mg; 524 μmol; 2.7 equiv.) was dissolved in MeCN (15 mL) followed by addition of dried K₂CO₃ (27 mg; 195 μmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of TD566 (50 mg; 193 μmol; 1.0 equiv.) in MeCN (15 mL) was added dropwise (over the course of 15 min). Resulting mixture was further stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 83 mg (69%; 1 step; based on TD566). NMR (CD₃CN): ¹H δ_H 1.33 (CH₃, s, 18H); 2.62 (mc, m, 4H); 2.66 (mc, m, 4H); 2.74 (mc, m, 4H); 2.80 (mc, m, 4H); 2.82 (CH₂—CO, s, 4H); 3.74 (CH₂-arom., s, 2H); 4.46 (CH₂—N₃, s, 2H); 2.46-7.58 (Ph, arom., m, 3+1H); 7.78-7.87 (Ph, m, 2H); 8.18 (arom., bs, 1H). ESI-HRMS: 623.4022 [M+H]⁺ (theor. [C₃₃H₅₁N₈O₄]⁺=623.4028).

Synthesis of TD711: In a pear-shape glass flask (100 mL), tBuDO2A (free base; 564 mg; 1.41 mmol; 2.5 equiv.) was dissolved in MeCN (40 mL). To the vigorously stirred reaction mixture, solution of TD406 (103 mg; 564 μmol; 1.0 equiv.) in MeCN (40 mL) was added dropwise (over the course of 2 h). Resulting mixture was further stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colourless oil. Yield: 217 mg (70%; 1 step; based on TD406). NMR (CD₃CN): ¹H δ_H 1.39 (CH₃, s, 18H); 2.55 (mc, m, 4H); 2.60 (mc, m, 4H); 2.76 (mc, m, 8H); 3.03 (CH₂—CO, s, 4H); 3.70 (CH₂-arom., s, 2H); 4.39 (CH₂—N₃, s, 2H); 7.21 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.67 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.73 (arom., t, 1H, ³J_HH=8). ¹³C{¹H} δ_C 28.4 (CH₃, s); 48.3 (mc, s); 51.8 (mc, s); 52.7 (mc, s); 54.7 (mc, s); 56.1 (CH₂—N₃, s); 57.7 (CH₂—CO, s); 59.0 (CH₂-arom., s); 81.2 (C—CH₃, s); 121.2 (arom., s); 124.1 (arom., s); 138.2 (arom., s); 155.6 (arom., s); 161.9 (arom., s); 172.0 (CO, s). ESI-HRMS: 547.3716 [M+H]⁺ (theor. [C₂₇H₄₇N₈O₄]⁺=547.3715).

Synthesis of TD596: In a pear-shape glass flask (25 mL), tBuDO2A (free base; 162 mg; 405 μmol; ≥2.5 equiv.) was dissolved in MeCN (10 mL). To the vigorously stirred reaction mixture, solution of crude TD633 (≤162 μmol; 1.0 equiv.) in MeCN (10 mL) was added dropwise (over the course of 15 min). Resulting mixture was further stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated and the aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 44 mg (48%; 2 steps; based on TD406). ESI-MS (LC-MS): 563.4 [M+H]⁺ (theor. [C₂₇H₄₇N₈O₅]⁺=563.4). All of TD596 was directly used for TD604 without further characterization.

Synthesis of TD1340: In a pear-shaped glass flask (50 mL), Cbz2cyclen (free base; 1.32 g; 3.0 mmol; 1.0 equiv.) was dissolved in dry MeCN (15 mL) followed by addition of dried K₂CO₃ (1.65 g; 12.0 mmol; 4.0 equiv.). Then, solution of TD1339 (1.50 g; 6.0 mmol; 2.0 N equiv.) in dry MeCN (5 mL) was added and the resulting suspension was stirred 8 h at RT. Solids were filtered off using syringe microfilter (PTFE) and the filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (150 mL) and H₂O (150 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 1.57 g (82%; 1 step; based on Cbz2cyclen). NMR (CD₃CN): ¹H δ_H 1.09 (CH₃—CH, d, 6H, ³J_HH=7); 1.19 (CH₃—CH₂, t, 6H, ³J_HH=7); 2.58-2.70 (mc, m, 4H); 2.76-2.98 (mc, m, 4H); 3.23-3.52 (mc, m, 8H); 3.52-3.79 (CH, m, 2H); 4.06 (CH₂—CH₃, q, 4H, ³J_HH=7); 5.00-5.13 (CH₂-Ph, m, 4H); 7.24-7.41 (Ph, m, 10H). ESI-HRMS: 641.3539 [M+H]⁺ (theor. [C₃₄H₄₉N₄O₈]⁺=641.3545).

Synthesis of TD1341: Pear-shaped glass flask (100 mL) was charged with Pd@C (127 mg) and magnetic stirrer and three times secured with argon. Solution of TD1340 (1.27 g; 1.98 mmol) in MeOH (50 mL) was then added through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 1 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colourless oil. Yield: 723 mg (98%; 1 step; based on TD1340). NMR (CD₃CN): ¹H δ_H 1.16-1.33 (CH₃, m, 12H); 2.35-2.45 (mc, m, 4H); 2.56-2.65 (mc, m, 4H); 2.65-2.76 (mc, m, 4H); 2.76-2.85 (mc, m, 4H); 3.54 (CH, q, 2H, ³J_HH=7); 4.00-4.24 (CH₂—CH₃, q, 4H, ³J_HH=7). ESI-HRMS: 372.2808 [M+H]⁺ (theor. [C₁₈H₃₇N₄O₄]⁺=373.2809).

Synthesis of TD1343: In a pear-shaped glass flask (50 mL), TD1341 (143 mg; 384 μmol; 2.0 equiv.) was dissolved in MeCN (15 mL) followed by addition of dried K₂CO₃ (26.3 mg; 191 μmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of TD558 (29.0 mg; 191 μmol; 1.0 equiv.) in MeCN (15 mL) was added dropwise (over the course of 15 min). Resulting mixture was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as nearly colourless oil. Yield: 46.0 mg (49%; 1 step; based on TD558). NMR (CD₃CN): ¹H δ_H 1.14 (CH₃—CH, d, 6H, ³J_HH=7); 1.19 (CH₃—CH₂, t, 6H, ³J_HH=7); 2.28-2.38 (mc, m, 4H); 2.45-2.59 (mc, m, 4H); 2.59-2.94 (mc, m, 8H); 3.23 (CH, q, 2H, ³J_HH=7); 3.41 (CH₂-arom., d, 1H, ²J_HH=15); 3.45 (C≡CH, s, 1H); 3.88 (CH₂-arom., d, 1H, ²J_HH=15); 4.06 (CH₂—CH₃, q, 4H, ³J_HH=7); 7.35-7.42 (arom., m, 1H); 7.66-7.79 (arom., m, 2H). ESI-HRMS: 488.3231 [M+H]⁺ (theor. [C₂₆H₄₂N₅O₄]⁺=488.3231).

Synthesis of TD1345: In a pear-shaped glass flask (25 mL), TD1343 (45.0 mg; 92 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (51 mg; 196 μmol; 4.0 equiv.). Solution of TD406 (20.0 mg; 110 μmol; 1.2 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 7 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as nearly colourless oil. Yield: 52.9 mg (90%; 1 step; based on TD1343). ESI-HRMS: 634.3825 [M+H]⁺ (theor. [C₃₃H₄₈N₉O₄]⁺=634.3824). All of TD1345 was directly used for TD1346 without further characterization.

Synthesis of TD1447: In a pear-shaped glass flask (100 mL), TD1341 (722 mg; 1.94 mmol; 2.0 equiv.) was dissolved in MeCN (40 mL) followed by addition of dried K₂CO₃ (133 mg; 964 μmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of TD1057 (241 mg; 962 μmol; 1.0 equiv.) in MeCN (40 mL) was added dropwise (over the course of 2 h). Resulting mixture was further stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (100 mL) and H₂O (100 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of formate salt as faint yellow oil. Yield: 367 mg (60% assuming M·1.0FA; M_R=632.7; 1 step; based on TD1057). Recovery: 352 mg of TD1341 (49% of the initial amount used). NMR (CD₃CN): ¹H δ_H 1.18 (CH₃—CH, d, 6H, ³J_HH=7); 1.21 (CH₃—CH₂, t, 6H, ³J_HH=7); 2.52-2.62 (mc, m, 4H); 2.64-2.76 (mc, m, 4H); 2.81-2.94 (mc, m, 4H); 2.95-3.06 (mc, m, 4H); 3.39 (CH—CH₃, q, 2H, ³J_HH=7); 3.81 (CH₂-arom., d, 1H, ²J_HH=15); 3.90 (CH₂-arom., d, 1H, ²J_HH=15); 4.09 (CH₂—CH₃, q, 4H, ³J_HH=7); 4.62 (CH₂—N₃, s, 2H); 7.58 (arom., d, 1H, ⁴J_HH=2); 7.66 (arom., d, 1H, ⁴J_HH=2). ¹⁹F δ_F −65.10 (s). ESI-HRMS: 587.3266 [M+H]⁺ (theor. [C₂₆H₄₂N₈O₄F₃]⁺=587.3276).

Synthesis of TD1449: In a pear-shaped glass flask (25 mL), TD1447 (assuming M·FA; 263.0 mg; 418 μmol; 1.0 equiv.) was dissolved in MeCN (5 mL) followed by addition of dried K₂CO₃ (231 mg; 1.67 μmol; 4.0 equiv.). Solution of TD1428 (173.0 mg; 421 μmol; 1.0 equiv.) in MeCN (10 mL) was then added and the resulting suspension was stirred 1 d at 40° C. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as yellow waxy oil. Yield: 309 mg (81%; 1 step; based on TD1447). NMR (CD₃CN): ¹H δ_H 1.10 (CH₃—CH, d, 6H, ³J_HH=7); 1.13 (CH₃—CH₂, t, 6H, ³J_HH=7); 1.43 (CH₃—C—O, s, 9H); 1.61 (CH₃—C—N, s, 6H); 2.53-2.80 (mc, m, 12H); 2.89-3.03 (mc, m, 4H); 3.32 (CH—CH₃, q, 2H, ³J_HH=7); 3.68 (CH₂-arom., s, 2H); 3.71 (CH₂-arom., d, 1H, ²J_HH=15); 3.77 (CH₂-arom., d, 1H, ²J_HH=15); 3.89 (CH₃—O, s, 3H); 3.99 (CH₂—CH₃, q, 4H, ³J_HH=7); 4.52 (CH₂—N₃, s, 2H); 5.56 (NH, bs, 1H); 7.50 (arom., d, 1H, ⁴J_HH=2); 7.71 (arom., d, 1H, ⁴J_HH=2); 8.00 (arom., d, 1H, ⁴J_HH=2); 8.16 (arom., d, 1H, ⁴J_HH=2). ¹⁹F δ_F −64.98 (s). ESI-HRMS: 917.4851 [M+H]⁺ (theor. [C₄₄H₆₄N₁₀O₈F₃]⁺=917.4855).

Synthesis of rac-TD1489: In a glass vial (20 mL), Cbz2cyclen (free base; 178 mg; 404 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (225 mg; 1.63 mmol; 4.0 equiv.). Then, solution of TD1488 (250 mg; 850 μmol; 2.1 equiv.) in MeCN (2 mL) was added and the resulting suspension was stirred 4 d at 40° C. (racemization occurred during the course of the reaction). Solids were filtered off using syringe microfilter (PTFE) and further washed with MeCN. The filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and concentrated on rotary evaporator to remove most of MeCN. Mixture was diluted with DCM (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 172 mg (73%; 1 step; based on Cbz2cyclen). ESI-MS (LC-MS): 585.3 [M+H]⁺ (theor. [C₃₀H₄₁N₄O₈]⁺=585.3).

Synthesis of TD1493: In a glass vial (20 mL), rac-TD1489 (free base; 172 mg; 294 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (162 mg; 1.17 mmol; 4.0 equiv.). Then, solution of TD1399 (148 mg; 592 μmol; 2.0 equiv.) in MeCN (2 mL) was added and the resulting suspension was stirred 70 min at 40° C. Solids were filtered off using syringe microfilter (PTFE) and further washed with MeCN. The filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with pure product (the more hydrophobic diastereomer differing in chirality of the malate arm was successfully separated) were combined, neutralized with dil. aq. NaHCO₃ and concentrated on rotary evaporator to remove most of MeCN. Mixture was diluted with DCM (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 88.1 mg (44%; 1 step; based on rac-TD1489). NMR (CD₃CN): ¹H δ_H 1.09 (CH₃—CH, d, 3H, ³J_HH=7); 1.19 (CH₃—CH₂, t, 3H, ³J_HH=7); 2.44 (CH₂—CH, dd, 1H, ²J_HH=17, ³J_HH=6); 2.55-2.70 (mc, CH₂—CH, m, 3+2H); 2.73-7.43 (Ph, m, 10H). ESI-HRMS: 685.3439 [M+H]⁺ (theor. [C₃₅H₄₉O₁₀N₄]⁺=685.3443).

Synthesis of TD1495: Pear-shaped glass flask (25 mL) was charged with Pd@C (9 mg) and magnetic stirrer and three times secured with argon. Solution of TD1493 (88.0 mg; 129 μmol) in MeOH (6 mL) was then added through septum. Argon input was then removed and H₂ gas (from balloon) was allowed to bubble through the mixture for 1 h at RT. Catalyst was then filtered off using syringe microfilter (PTFE; filter was further washed with MeOH). Filtrate was evaporated to dryness and once co-evaporated with DCM. The residue was further dried on high vacuum overnight to give product in the form of free base as colourless oil. Yield: 52.6 mg (98%; 1 step; based on TD1493). ESI-HRMS: 417.2706 [M+H]⁺ (theor. [C₁₉H₃₇O₆N₄]⁺=417.2708).

Synthesis of TD1497: In a pear-shaped glass flask (25 mL), TD1495 (55 mg; 132 μmol; 1.7 equiv.) was dissolved in MeCN (5 mL) followed by addition of dried K₂CO₃ (11.0 mg; 80 μmol; 1.0 equiv.). To the vigorously stirred reaction mixture, solution of TD558 (12.0 mg; 79 μmol; 1.0 equiv.) in MeCN (5 mL) was added dropwise (over the course of 15 min). Resulting mixture was stirred 4 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×10 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as nearly colourless oil. Yield: 12.1 mg (29%; 1 step; based on TD558). ESI-MS (LC-MS): 532.3 [M+H]⁺ (theor. [C₂₇H₄₂N₅O₆]⁺=532.3).

Synthesis of TD1500: In a glass vial (4 mL), TD1497 (12.1 mg; 23 μmol; 1.0 equiv.) was dissolved in solution of TD406 (5.8 mg; 32 μmol; 1.4 equiv.) in MeCN (2 mL) followed by addition of dried K₂CO₃ (17.5 mg; 127 μmol; 4.0 equiv.). The resulting suspension was stirred 1 d at 40° C. Solids were filtered off using syringe microfilter (PTFE) and filtrate was diluted with H₂O (1 mL). Resulting solution was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (25 mL) and H₂O (25 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (4×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further briefly dried on high vacuum to give product in the form of free base as faint yellow oil. Yield: 11.9 mg (77%; 1 step; based on TD1497). ESI-MS (LC-MS): 678.3 [M+H]⁺ (theor. [C₃₄H₄₈N₉O₆]⁺=678.4).

Example 4: Synthesis of Non-Caged Macrocyclic Ligands

Synthesis of TD425: In a pear-shape glass flask (50 mL), crude TD423 (˜75% in a mixture with ˜25% of bis(substituted) by-product; 180 mg; ≥1.0 equiv.) was dissolved in dry MeCN (10 mL) followed by addition of Cs₂CO₃ (360 mg; 1.11 mmol; 3.8 equiv.). Solution of TD566 (75 mg; 290 μmol; 1.0 equiv.) in MeCN (5 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 129 mg (27%; 3 steps; based on 2-Chloro-N-(prop-2-yn-1-yl)acetamide). NMR (D₂O, pD ˜5): ¹H δ_H 2.62 (C≡CH, t, 1H, ⁴J_HH=3); 2.89-3.74 (mc, CH₂—CO, m, 16+6H); 3.79 (CH₂—C≡CH, t, 2H, ⁴J_HH=3); 4.03 (CH₂-arom., bs, 2H); 4.68 (CH₂—N₃, s, 2H); 7.55-7.67 (Ph, arom., m, 3+1H); 7.78 (arom., d, 1H, ⁴J_HH=2); 7.85-7.92 (Ph, m, 2H); 8.17 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 606.3151 [M+H]⁺ (theor. [C₃₀H₄₀N₉O₅]⁺=606.3147). EA (C₃₀H₃₉N₉O₅·0.1FA·1.3H₂O, M_R=633.7): C 57.0 (56.8); H 6.6 (6.3); N 19.9 (19.5).

Synthesis of TD669: In a glass vial (4 mL), TD663 (30 mg; 48 μmol, 1.0 equiv.) was dissolved in dry MeCN (500 μL) followed by addition of K₂CO₃ (20 mg; 145 μmol; 3 equiv.). Solution of TD662 (10 mg; 50 μmol; 1.0 equiv.) in MeCN (500 μL) was then added and the resulting suspension was stirred 2 d at RT. Another portion of TD662 (6 mg; 30 μmol; 0.6 equiv.) in MeCN (200 μL) was then added and the mixture was further stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 27 mg (≤88% assuming M·0.1FA·xH₂O; M_R=634.4; 2 steps; based on TD663). NMR (D₂O, pD ˜5): ¹H δ_H 2.59-3.82 (mc, CH₂—CO, CH₂—CH₂—N(CH₂—C≡CH)₂, m, 16+4+10H); 4.00 (CH₂-arom., bs, 2H); 4.64 (CH₂—N₃, s, 2H); 7.55-7.65 (Ph, m, 3H); 7.74 (arom., d, 1H, ⁴J_HH=2); 7.83-7.91 (Ph, m, 2H); 8.17 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 630.3510 [M+H]⁺ (theor. [C₃₃H₄₄N₉O₄]⁺=630.3511).

Synthesis of TD604: In a glass vial (4 mL), TD596 (44 mg; 78 μmol; 1.0 equiv.) was dissolved in MeCN (3 mL) followed by addition of dried K₂CO₃ (33 mg; 239 μmol; 3.0 equiv.). Solution of TD558 (13 mg; 86 μmol; 1.1 equiv.) in MeCN (600 μL) was then added and the resulting suspension was stirred 16 d at RT. Then additional portion of TD558 (2 mg; 13 μmol; 0.2 equiv.) in MeCN (400 μL). Reaction mixture was further stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 38 mg (81%; 2 steps; based on TD596). NMR (D₂O, pD ˜4): ¹H δ_H 2.80-3.68 (mc, CH₂—CO, m, 16+4H); 3.72 (C≡CH, s, 1H); 3.93 (CH₂-arom., bs, 2H); 4.17 (CH₂-arom., s, 2H); 4.74 (CH₂—N₃, s, 2H); 7.48-7.67 (arom., m, 3H); 7.74-7.95 (arom., m, 3H). ¹³C{¹H} δ_C 48.3 (mc, s); 48.9 (mc, s); 50.6 (CH₂—N₃, s); 51.4 (CH₂-arom., s); 51.5 (mc, s); 51.7 (mc, s); 56.7 (CH₂—CO, s); 58.8 (CH₂-arom., s); 80.7 and 82.2 (C≡CH; 2×s); 126.0 (arom., s); 126.5 (arom., s); 127.9 (arom., s); 128.5 (arom., s); 131.5 (arom., s); 140.3 (arom., s); 141.2 (arom., s); 148.4 (arom., s); 148.7 (arom., s); 157.3 (arom., s); 169.5 (CO, s). ESI-HRMS: 566.2836 [M+H]⁺ (theor. [C₂₇H₃₆N₉O₅]⁺=566.2834). EA (C₂₇H₃₅N₉O₅·0.1FA·1.6H₂O, M_R=599.1): C 54.3 (54.4); H 6.5 (6.1); N 21.0 (20.7).

Synthesis of TD556: In a pear-shape glass flask (25 mL), TD635 (216 mg; 419 μmol; 1.0 equiv.) was dissolved in MeCN (12 mL) followed by addition of dried K₂CO₃ (174 mg; 1.26 mmol; 3.0 equiv.). Solution of TD406 (92 mg; 504 μmol; 1.2 equiv.) in MeCN (3 mL) was then added and the resulting suspension was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 161 mg (66%; 2 steps; based on TD635). NMR (D₂O, pD ˜4): ¹H δ_H 2.80-3.60 (mc, CH₂—CO, m, 16+4H); 3.74 (C≡CH, s, 1H); 3.86 (CH₂-arom., bs, 2H); 3.94 (CH₂-arom., bs, 2H); 4.72 (CH₂—N₃, s, 2H); 7.65 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.67 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.95-8.03 (arom., m, 3H); 8.12 (arom., t, 1H, ³J_HH=8); ¹³C{¹H} δ_C 48.3 (mc, s); 48.4 (mc, s); 51.4 (mc, s); 51.5 (mc, s); 54.3 (CH₂—N₃, s); 56.6 (CH₂—CO, s); 58.0 (CH₂-arom., s); 58.9 (CH₂-arom., s); 80.9 and 82.0 (C≡CH; 2×s); 124.5 (arom., s); 126.2 (arom., s); 126.3 (arom., s); 128.5 (arom., s); 140.5 (arom., s); 141.2 (arom., s); 142.7 (arom., s); 155.0 (arom., s); 155.5 (arom., s); 157.2 (arom., s); 169.2 (CO, s). ESI-HRMS: 550.2880 [M+H]⁺ (theor. [C₂₇H₃₆N₉O₄]⁺=550.2885). EA (C₂₇H₃₅N₉O₄·0.1FA·1.6H₂O, M_R=583.1): C 55.8 (55.5); H 6.6 (6.1); N 21.6 (21.2).

Synthesis of TD810: In a glass vial (20 mL), TD711 (103 mg; 188 μmol; 1.0 equiv.) was dissolved in MeCN (5 mL) followed by addition of dried K₂CO₃ (130 mg; 942 μmol; 5.0 equiv.). Solution of TD807 (33 mg; 188 μmol; 1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of mixed trifluoroacetate/formate salt as off white fluffy solid. Yield: 55 mg (43%; 2 steps; based on TD711). NMR (D₂O, pD ˜4): ¹H δ_H 2.79-3.63 (mc, CH₂—CO, m, 16+4H); 3.74 (C≡CH, s, 1H); 3.82 (CH₂-arom., bs, 2H); 3.87 (CH₂-arom., bs, 2H); 3.92 (C≡CH, s, 1H); 4.63 (CH₂—N₃, s, 2H); 7.55 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.72 (arom., d, 1H, ⁴J_HH=1); 8.10 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.16 (arom., t, 1H, ³J_HH=8); 8.26 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 574.2882 [M+H]⁺ (theor. [C₂₉H₃₆N₉O₄]⁺=574.2885). EA (C₂₉H₃₅N₉O₄·0.5TFA·0.1FA·2.1H₂O, M_R=673.1): C 53.7 (53.8); H 6.0 (6.2); N 18.7 (18.7).

Synthesis of TD827: In a glass vial (20 mL), TD635 (157 mg; 304 μmol; 1.0 equiv.) was dissolved in dry MeCN (7 mL) followed by addition of dried K₂CO₃ (210 mg; 1.52 mmol; 5.0 equiv.). Solution of TD817 (110 mg; 303 μmol; 1.0 equiv.) in dry MeCN (3 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, concentrated to approx. half volume (to remove most of MeCN) and then diluted with DCM (125 mL). The resulting biphasic mixture was transferred to a separatory funnel. Aqueous phase was only then neutralized with dil. aq. NaHCO₃. After shaking, the bottom phase was separated and the aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and once co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as off white fluffy solid. Yield: 149 mg (62%; 2 steps; based on TD711). NMR (D₂O+FA, pD ˜3): ¹H δ_H 0.86-1.33 (i-Pr, m, 21H); 2.58-3.78 (mc, CH₂—CO, C—CH, bm, 16+4+1H); 3.93 (CH₂-arom., bs, 2H); 4.06 (CH₂-arom., bs, 2H); 4.56 (CH₂—N₃, s, 2H); 7.37 (arom., s, 1H); 7.53 (arom., d, 1H, ³J_HH=8); 7.74 (arom., s, 1H); 7.80 (arom., d, 1H, ³J_HH=8); 7.96 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 730.4216 [M+H]⁺ (theor. [C₃₈H₅₆N₉O₄Si₁]⁺=730.4219). EA (C₃₈H₅₅N₉O₄Si₁·0.8FA·1.6H₂O, M_R=795.6): C 58.6 (58.7); H 7.6 (7.7); N 15.8 (15.7); Si 3.5 (3.2).

Synthesis of TD718: In a pear-shape glass flask (10 mL), TD711 (31 mg; 57 μmol; 1.0 equiv.) was dissolved in dry MeCN (2 mL) followed by addition of dried K₂CO₃ (31 mg; 225 μmol; 4.0 equiv.). Solution of TD706 (13 mg; 58 μmol; 1.0 equiv.) in dry MeCN (2 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, diluted with DCM (100 mL) and transferred to a separatory funnel. Aqueous phase was only then neutralized with dil. aq. NaHCO₃. After shaking, bottom phase was separated, dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and once co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as white fluffy solid. Yield: 23 mg (61%; 2 steps; based on TD706). NMR (D₂O, pD ˜5): ¹H δ_H 0.28 (CH₃, s, 9H); 2.28-3.67 (mc, CH₂—CO, m, 16+4H); 3.89 (CH₂-arom., bs, 4H); 4.57 (CH₂—N₃, s, 2H); 7.49 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.58-7.64 (arom., m, 1H); 7.78-7.98 (arom., m, 4H). ESI-HRMS: 622.6277 [M+H]⁺ (theor. [C₃₀H₄₄N₉O₄Si₁]⁺=622.3280). EA (C₃₀H₄₃N₉O₄Si₁·2.6H₂O, M_R=668.7): C 53.9 (53.9); H 7.3 (7.0); N 18.9 (18.7).

Synthesis of TD728: In a pear-shape glass flask (10 mL), TD711 (66 mg; 121 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (67 mg; 486 μmol; 4.0 equiv.). Solution of TD723 (37 mg; 120 μmol; 1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, diluted with DCM (150 mL) and the resulting biphasic mixture was transferred to a separatory funnel. Aqueous phase was only then neutralized with dil. aq. NaHCO₃. After shaking, the bottom phase was separated and the aqueous phase was further extracted with DCM (2×50 mL). Combined organic layers were with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and once co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as white fluffy solid. Yield: 64 mg (71%; 2 steps; based on TD723). NMR (D₂O, pD ˜5): ¹H δ_H 0.84-1.34 (i-Pr, m, 21H); 2.41-3.78 (mc, CH₂—CO, m, 16+4H); 3.89 (CH₂-arom., bs, 2H); 3.95 (CH₂-arom., bs, 2H); 4.52 (CH₂—N₃, s, 2H); 7.42 (arom., d, 1H, ³J_HH=8); 7.46 (arom., d, 1H, ³J_HH=8); 7.74 (arom., d, 1H, ³J_HH=8); 7.78 (arom., d, 1H, ³J_HH=8); 7.85 (arom., t, 1H, ³J_HH=8); 7.87 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 706.4221 [M+H]⁺ (theor. [C₃₆H₅₆N₉O₄Si₁]⁺=706.4219). EA (C₃₆H₅₅N₉O₄Si₁·2.6H₂O, M_R=752.8): C 57.4 (57.7); H 8.1 (8.0); N 16.7 (16.5); Si 3.7 (3.8).

Synthesis of TD1204: In a glass vial (20 mL), TD711 (35.0 mg; 64.0 μmol; 1.0 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (44.2 mg; 320 μmol; 5.0 equiv.). Solution of TD1194 (21.4 mg; 77.1 μmol; 1.2 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 23.3 mg (49%; 2 steps; based on TD711). NMR (D₂O, pD ˜7): ¹H δ_H 2.83-3.67 (mc, CH₂—CO, m, 16+4H); 3.88 (CH₂-arom., bs, 2H); 3.92 (CH₂-arom., bs, 2H); 4.56 (CH₂—N₃, s, 2H); 7.49 (arom., d, 1H, ³J_HH=8); 7.54 (arom., d, 1H, ³J_HH=8); 7.87-8.00 (arom., m, 4H). ESI-HRMS: 676.1855 [M+H]⁺ (theor. [C₂₇H₃₅N₉O₄I₁]⁺=676.1851). EA (C₂₇H₃₄N₉O₄I₁·0.3FA·2.7H₂O, M_R=738.0): C 44.4 (44.6); H 5.5 (5.1); N 17.1 (16.7).

Synthesis of TD944: In a pear-shape glass flask (10 mL), TD711 (58 mg; 106 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (87 mg; 629 μmol; 6.0 equiv.). Solution of freshly prepared and isolated TD939 (≤105 μmol; ≤1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as faint yellow solid. Yield: 38 mg (55%; 3 steps; based on TD936). NMR (D₂O, pD ˜7): ¹H δ_H 2.82-3.67 (mc, CH₂—CO, m, 16+4H); 3.91 (CH₂-arom., bs, 2H); 3.95 (CH₂-arom., bs, 2H); 4.58 (CH₂—N₃, s, 2H); 7.40-8.07 (Ph, arom., m, 5+6H). ESI-HRMS: 626.3197 [M+H]⁺ (theor. [C₃₃H₄₀N₉O₄]⁺=626.3198). EA (C₃₀H₃₉N₉O₄·1.5H₂O, M_R=652.8): C 60.7 (61.0); H 6.5 (6.3); N 19.3 (18.8).

Synthesis of TD943: In a pear-shape glass flask (10 mL), TD711 (82 mg; 150 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (125 mg; 904 μmol; 6.0 equiv.). Solution of freshly prepared and isolated TD940 (≤150 μmol; ≤1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as faint yellow solid. Yield: 66 mg (71%; 3 steps; based on TD937). NMR (D₂O, pD ˜7): ¹H δ_H 0.74-1.06 (CH₂—CH, m, 4H); 1.35-1.66 (CH₂—CH, m, 1H); 2.69-3.65 (mc, CH₂—CO, m, 16+4H); 3.86 (CH₂-arom., bs, 2H); 3.92 (CH₂-arom., bs, 2H); 4.57 (CH₂—N₃, s, 2H); 7.42-7.53 (arom., m, 2H); 7.83-8.01 (arom., m, 4H). ESI-HRMS: 590.3196 [M+H]⁺ (theor. [C₃₀H₄₀N₉O₄]⁺=590.3198). EA (C₃₀H₃₉N₉O₄·1.5H₂O, M_R=616.7): C 58.4 (58.6); H 6.9 (6.9); N 20.4 (20.3).

Synthesis of TD959: In a pear-shape glass flask (10 mL), TD711 (23 mg; 42 μmol; 1.0 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (35 mg; 253 μmol; 6.0 equiv.). Solution of freshly prepared and isolated TD956 (≤42 μmol; ≤1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as nearly colourless solid. Yield: 18 mg (67%; 3 steps; based on TD952). NMR (D₂O, pD ˜6): ¹H δ_H 1.34 (CH₃, s, 9H); 2.72-3.69 (mc, CH₂—CO, m, 16+4H); 3.88 (CH₂-arom., bs, 2H); 3.92 (CH₂-arom., bs, 2H); 4.57 (CH₂—N₃, s, 2H); 7.46-7.55 (arom., m, 2H); 7.84-8.03 (arom., m, 4H). ESI-HRMS: 606.3513 [M+H]⁺ (theor. [C₃₁H₄₄N₉O₄]⁺=606.3511). EA (C₃₁H₄₃N₉O₄·1.8H₂O, M_R=638.2): C 58.3 (58.7); H 7.4 (7.0); N 19.8 (19.4

Synthesis of TD992: In a glass vial (4 mL), TD711 (43 mg; 79 μmol; 1.0 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (44 mg; 318 μmol; 4.1 equiv.). Solution of freshly prepared and isolated TD990 (≤79 μmol; ≤1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 16 h at 40° C. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as off white fluffy solid. Yield: 42.0 mg (73%; 3 steps; based on TD965). NMR (D₂O, pD ˜5): ¹H δ_H 1.62-1.83 (Adm., m, 6H); 1.86-2.04 (Adm., m, 9H); 2.77-3.70 (mc, CH₂—CO, m, 16+4H); 3.90 (CH₂-arom., bs, 2H); 3.94 (CH₂-arom., bs, 2H); 4.57 (CH₂—N₃, s, 2H); 7.44-7.56 (arom., m, 2H); 7.82-8.00 (arom., m, 4H). ESI-HRMS: 684.3982 [M+H]⁺ (theor. [C₃₇H₅₀N₉O₄]⁺=684.3980). EA (C₃₇H₄₉N₉O₄·0.3FA·1.9H₂O, M_R=731.9). C 61.2 (61.2); H 7.1 (7.1); N 17.2 (17.0).

Synthesis of TD703: In a glass vial (20 mL), TD692 (38 mg; 76 μmol; 1.0 equiv.) was dissolved in MeCN (3 mL) followed by addition of dried K₂CO₃ (31 mg; 217 μmol; 3.0 equiv.). Solution of TD406 (14 mg; 77 μmol; 1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 16 h at RT. Then, another portion of dried K₂CO₃ (31 mg; 217 μmol; 3.0 equiv.) and of TD406 (10 mg; 55 μmol; 0.7 equiv.) in MeCN (1 mL) was added and the resulting suspension was further stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with protected product were combined, evaporated to dryness and further two-times co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and three-times co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were Joined and directly lyophilized to give product in the form of mixed trifluoroacetate/formate salt as slightly yellow viscous oil. Yield: 16 mg (34%; 2 steps; based on TD692). NMR (D₂O, pD ˜5): ¹H δ_H 2.59-3.73 (mc, CH₂—CO, m, 16+2H); 3.75 (C≡CH, s, 1H); 3.84 (CH₂-arom., bs, 2H); 4.29-4.62 (CH₂-arom., CH₂—N₃, m, 2+2H); 7.37 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.45 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.52 (arom., t, 1H, ³J_HH=8); 7.56 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.59 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 492.2829 [M+H]⁺ (theor. [C₂₅H₃₄N₉O₂]⁺=492.2830). EA (C₂₅H₃₃N₉O₂·0.3TFA·0.7FA·3.5H₂O, M_R=621.1): C 50.9 (51.1); H 6.8 (6.8); N 20.3 (20.0).

Synthesis of TD705: In a glass vial (20 mL), TD700 (20 mg; 36 μmol; 1.0 equiv.) was dissolved in MeCN (3 mL) followed by addition of dried K₂CO₃ (20 mg; 145 μmol; 4.0 equiv.). Solution of TD406 (9 mg; 49 μmol; 1.4 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 22 mg (87%; 1 step; based on TD406). ESI-MS (LC-MS): 698.4 [M+H]⁺ (theor. [C₃₄H₅₃N₉O₅P₁]⁺=698.4). All of TD705 was directly used for TD714 without further characterization.

Synthesis of TD714: In a glass vial (4 mL), TD705 (22 mg; 32 μmol; 1.0 equiv.) was dissolved in dry Pyridine (1 mL) followed by addition of neat TMSBr (50 μL; 379 μmol; 12.0 equiv.) and the resulting mixture was stirred 16 h at RT. Reaction was then quenched with 50% aq. MeOH (1 mL) and the mixture was further stirred 1 h at RT. The mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and further two-times co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 12 mg (≤64% assuming M·0.1FA·xH₂O; M_R=590.2; 2 steps; based on TD705). NMR (D₂O, pD ˜5): ¹H δ_H 2.73-3.71 (mc, CH₂—CO, CH₂—P, m, 16+2+1H); 3.74 (C≡CH, s, 1H); 3.84 (CH₂-arom, bs, 1H); 3.99 (CH₂-arom., bs, 1H); 4.17 (CH₂-arom., bs, 2H); 4.47 (CH₂—P; bd, ²J_HH=13); 4.67 (CH₂—N₃, s, 1H); 4.68 (CH₂—N₃, s, 1H); 7.54 (arom., d, 1H, ³J_HH=8); 7.61 (arom., d, 1H, ³J_HH=8); 7.62 (arom., d, 1H, ³J_HH=8); 7.64 (arom., d, 1H, ³J_HH=8); 7.90 (arom., t, 1H, ³J_HH=8); 7.93 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 586.2649 [M+H]⁺ (theor. [C₂₆H₃₇N₉O₅P₁]⁺=586.2650).

Synthesis of TD921: In a pear-shape glass flask (25 mL), TD910 (160 mg; 315 μmol; 2.0 equiv.) was dissolved in MeCN (10 mL) followed by addition of solution of dried K₂CO₃ (22 mg; 160 μmol; 1.0 equiv.). Solution of TD558 (24 mg; 158 μmol; 1.0 equiv.) in MeCN (5 mL) was then added dropwise over the course of 15 min and the resulting suspension was stirred for 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was s dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The resulting alkyne bearing intermediate (together with partially N-methylated/demethylated by-products as a consequence of ongoing self-methylation; 49 mg; ≤78 μmol; ≤1.0 equiv.) was dissolved in MeCN (7 mL) followed by addition of TD406 (18 mg; 119 μmol; ≥1.5 equiv.) and K₂CO₃ (54 mg; 391 μmol; ≥5.0 equiv.) and the resulting suspension was stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was s dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The resulting methyl ester of product (together with partially N-methylated/demethylated by-products as a consequence of ongoing self-methylation; 37 mg; ≤48 μmol; ≤1.0 equiv.) was dissolved in dry Pyridine (2 mL) followed by addition of neat TMSBr (65 μL; 492 μmol; ≥12.0 equiv.) and the resulting mixture was stirred 16 h at RT. Reaction was then quenched with 50% aq. MeOH (1 mL) and the mixture was further stirred 1 h at RT. The mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as white fluffy solid. Yield: 25.6 mg (20%; 3 steps; based on TD558). NMR (D₂O, pD ˜4): ¹H δ_H 2.56-3.75 (mc, CH₂—P, C≡CH, m, 16+4+1H); 4.20 (CH₂-arom., bs, 2H); 4.29 (CH₂-arom., bs, 2H); 4.45 (CH₂—N₃, s, 2H); 7.23-7.77 (Ph, arom., m, 10+4H); 7.96 (arom., t, 1H, ³J_HH=8); 7.97 (arom., t, 1H, ³J_HH=8). ³¹P{¹H} δ_P 25.1 (bs). ESI-HRMS: 796.2334 [M+H]⁺ (theor. [C₄₄H₃₄N₁₀O₂P₂]⁺=796.2336). EA (C₃₇H₄₅N₉O₄P₂·4.6H₂O, M_R=824.6): C 53.9 (54.5); H 6.6 (6.3); N 15.3 (14.7).

Synthesis of TD580: In a glass vial (20 mL), TD579 (137 mg; 233 μmol; 1.0 equiv.) was dissolved in MeCN (7 mL) followed by addition of dried K₂CO₃ (141 mg; 1.02 mmol; 4.4 equiv.). Solution of TD406 (50 mg; 274 μmol; 1.2 equiv.) in MeCN (3 mL) was then added and the resulting suspension was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×50 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as colorless oil. Yield: 125 mg (73%; 1 step; based on TD579). NMR (CD₃CN): ¹H δ_H 1.21 (CH₃, t, 12H, ³J_HH=7); 2.90 (mc, m, 8H); 2.97 (CH₂—P, d, 4H, ²J_HP=10); 2.99 (mc, m, 4H); 3.24 (mc, m, 8H); 3.55 (C≡CH, s, 1H); 4.01 (CH₂—O—P, m, 8H); 4.21 (CH₂-arom., s, 2H); 4.48 (CH₂—N₃, s, 2H); 4.55 (CH₂-arom., s, 2H); 7.37 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.49 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.51 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.54 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.80 (arom., t, 1H, ³J_HH=8); 7.84 (arom., t, 1H, ³J_HH=8)³¹P{¹H} δ_P 24.8 (s). ESI-MS (LC-MS): 734.5 [M+H]⁺ (theor. [C₃₃H₅₄N₉O₆P₂]⁺=734.4).

Synthesis of TD582: In a glass vial (4 mL), TD580 (25 mg; 34 μmol; 1.0 equiv.) was dissolved in a mixture of aq. NaOH (10%; 1 mL) and EtOH (300 μL) and the resulting solution was stirred 2 d at RT. Reaction was then quenched with AcOH (200 μL) and the mixture was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 9 mg (≤39% assuming M·0.1FA·xH₂O; M_R=682.3; 1 step; based on TD580). ESI-MS (LC-MS): 678.4 [M+H]⁺ (theor. [C₂₉H₄₆N₉O₆P₂]⁺=678.3).

Synthesis of TD581: In a glass vial (4 mL), TD580 (25 mg; 34 μmol; 1.0 equiv.) was dissolved in dry Pyridine (1 mL) followed by addition of neat TMSBr (110 μL; 833 μmol; ˜25 equiv.) and the resulting mixture was stirred 16 h at RT. Reaction was then quenched with 50% aq. MeOH (1 mL) and the mixture was further stirred 1 h at RT. The mixture was then directly purified preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as slightly yellow fluffy solid. Yield: 6 mg (≤28% assuming M·0.1FA·xH₂O; M_R=626.2; 1 step; based on TD580). ESI-MS (LC-MS): 622.3 [M+H]⁺ (theor. [C₂₅H₃₈N₉O₆P₂]⁺=622.2).

Synthesis of TD575: In a glass vial (20 mL), TD579 (51 mg; 87 μmol; 1.2 equiv.) was dissolved in MeCN (3 mL) followed by addition of dried K₂CO₃ (30 mg; 217 μmol; 3.0 equiv.). Solution of TD566 (20 mg; 73 μmol; 1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were combined, neutralized with dil. aq. NaHCO₃ and evaporated to dryness. Residue was dissolved in DCM (50 mL) and H₂O (50 mL) and transferred to a separatory funnel. After shaking, the bottom phase was separated. Aqueous phase was further extracted with DCM (3×25 mL). Combined organic layers were dried with anhydrous Na₂SO₄, filtered through glass frit (S3) and evaporated to dryness. The residue was further dried on high vacuum overnight to give product in the form of free base as nearly colorless oil. Yield: 46 mg (90%; 1 step; based on TD566). ESI-MS (LC-MS): 810.4 [M+H]⁺ (theor. [C₃₉H₅₈N₉O₆P₂]⁺=810.4). TD575 was directly used for TD576 and without further characterization.

Synthesis of TD576: In a glass vial (4 mL), TD575 (23 mg; 28 μmol; 1.0 equiv.) was dissolved in dry Pyridine (1 mL) followed by addition of neat TMSBr (220 μL; 1.67 mmol; ˜60 equiv.) and the resulting mixture was stirred 16 h at RT. Reaction was then quenched with 50% aq. MeOH (1 mL) and the mixture was further stirred 1 h at RT. The mixture was then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 15 mg (≤75% assuming M·0.1FA·xH₂O; M_R=702.3; 1 step; based on TD575). NMR (D₂O+NaOD, pD ˜8): ¹H δ_H 2.54-3.76 (mc, CH₂—P, m, 16+4H); 3.93 (CH₂-arom., bs, 2H); 4.10 (CH₂-arom., bs, 2H); 4.60 (CH₂—N₃, s, 2H); 7.44 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.46-7.51 (Ph, m, 3H); 7.53 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.66-7.70 (Ph, m, 2H); 7.71 (arom., d, 1H, ⁴J_HH=2); 7.77 (arom., d, 1H, ⁴J_HH=2); 7.81 (arom., t, 1H, ³J_HH=8). ³¹P{¹H} δ_P 8.2 (bs). ESI-HRMS: 696.2575 [M−H]⁻ (theor. [C₃₁H₄₀N₉O₆P₂]⁻=696.2582).

Synthesis of TD801: In a glass vial (20 mL), TD799 (46 mg; 85 μmol; 1.0 equiv.) was dissolved in MeCN (5 mL) followed by addition of dried K₂CO₃ (48 mg; 348 μmol; 4.1 equiv.). Solution of TD406 (20 mg; 110 μmol; 1.3 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 33 mg (48%; 2 steps; based on TD799). NMR (D₂O, pD ˜3): ¹H δ_H 2.41-3.78 (mc, CH₂—CO, CH₂—P, m, 16+2+2H); 3.89 (CH₂-arom., bs, 2H); 3.95 (CH₂-arom., bs, 2H); 4.52 (CH₂—N₃, s, 2H); 7.42 (arom., d, 1H, ³J_HH=8); 7.46 (arom., d, 1H, ³J_HH=8); 7.74 (arom., d, 1H, ³J_HH=8); 7.78 (arom., d, 1H, ³J_HH=8); 7.85 (arom., t, 1H, ³J_HH=8); 7.87 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 578.3208 [M+H]⁺ (theor. [C₂₉H₄₀N₉O₄]⁺=578.3203). EA (C₂₉H₃₉N₉O₄·2.0TFA, M_R=805.7): C 49.2 (49.3); H 5.1(5.4); N 15.6 (15.7).

Synthesis of TD764: In a glass vial (20 mL), TD635 (304 mg; 589 μmol; 1.1 equiv.) was dissolved in MeCN (7 mL) followed by addition of dried K₂CO₃ (305 mg; 2.21 mmol; 4.0 equiv.). Solution of TD760 (120 mg; 553 μmol; 1.0 equiv.) in MeCN (3 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 196 mg (51%; 2 steps; based on TD635). NMR (D₂O, pD ˜3): ¹H δ_H 2.86-3.60 (mc, CH₂—CO, m, 16+4H); 3.77 (C≡CH, s, 1H); 3.79-4.06 (CH₂-arom., bm, 4H); 4.62 (CH₂—N₃, s, 2H); 7.62 (arom., d, 1H, ⁴J_HH=2); 7.67-7.73 (arom., m, 1H); 8.07-8.14 (arom., m, 2H); 8.17 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 582.2344 [M−H]⁻ (theor. [C₂₇H₃₃N₉O₄Cl₁]⁻=582.2350). EA (C₂₇H₃₄N₉O₄Cl₁·0.7TFA·1.7H₂O, M_R=694.5): C 49.1 (49.0); H 5.5 (5.4); N 18.2 (18.4); Cl 5.1 (5.3).

Synthesis of TD1063: In a glass vial (4 mL), TD635 (50 mg; 97 μmol; 1.0 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (67 mg; 485 μmol; 5.0 equiv.). Solution of TD1057 (24 mg; 96 μmol; 1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 33.4 mg (55%; 2 steps; based on TD635). NMR (D₂O, pD ˜7): ¹H δ_H 2.81-3.68 (mc, CH₂—CO, m, 16+4H); 3.72 (C≡CH, s, 1H); 3.82 (CH₂-arom., bs, 2H); 4.05 (CH₂-arom., bs, 2H); 4.70 (CH₂—N₃, s, 2H); 7.62-7.69 (arom., m, 1H); 7.82 (arom., s, 1H); 7.92-7.99 (arom., m, 2H); 8.38 (arom., s, 1H). ¹⁹F{¹H} δ_F −64.2 (s). ESI-HRMS: 618.2759 [M+H]⁺ (theor. [C₂₈H₃₅N₉O₄F₃]⁺=618.2759). EA (C₂₈H₃₄N₉O₄F₃·0.1FA·1.2H₂O, M_R=643.8): C 52.4 (52.8); H 5.7 (5.4); N 19.6 (19.4); F 8.8 (7.8).

Synthesis of TD1092: In a glass vial (4 mL), TD635 (35 mg; 68 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (44 mg; 318 μmol; 4.7 equiv.). Solution of pre-purified TD1089 (containing ˜20% of the bis azide byproduct; 20 mg; <83 μmol; <1.2 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 31.9 mg (74%; 2 steps; based on TD635). NMR (D₂O, pD ˜6): ¹H δ_H 2.76-3.62 (mc, CH₂—CO, m, 16+4H); 3.73 (C≡CH, s, 1H); 3.83 (CH₂-arom., bs, 2H); 3.99 (CH₃, s, 3H); 4.05 (CH₂-arom., bs, 2H); 4.69 (CH₂—N₃, s, 2H); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.02 (arom., d, 1H, ⁴J_HH=1); 8.05 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.15 (arom., t, 1H, ³J_HH=8); 8.58 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 608.2939 [M+H]⁺ (theor. [C₂₉H₃₈N₉O₆]⁺=608.2940). EA (C₂₉H₃₇N₉O₆·0.1FA·1.1H₂O, M_R=632.1): C 55.3 (55.1); H 6.3 (6.0); N 19.9 (19.6).

Synthesis of TD1148: In a glass vial (4 mL), TD635 (44 mg; 85 μmol; 1.0 equiv.) was dissolved in MeCN (2.5 mL) followed by addition of dried K₂CO₃ (47 mg; 340 μmol; 4.0 equiv.). Solution of TD1112 (23 mg; 86 μmol; 1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 30.7 mg (55%; 2 steps; based on TD635). NMR (D₂O, pD ˜6): ¹H δ_H 1.40 (CH₃, d, 6H, ³J_HH=6); 2.77-3.63 (mc, CH₂—CO, m, 16+4H); 3.70 (C≡CH, s, 1H); 3.80 (CH₂-arom., bs, 2H); 4.06 (CH₂-arom., bs, 2H); 4.65 (CH₂—N₃, s, 2H); 5.26 (CH, hept, 1H, ³J_HH=6); 7.65 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.93-8.00 (arom., m, 2H); 8.12 (arom., t, 1H, ³J_HH=8); 8.45 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 636.3247 [M+H]⁺ (theor. [C₃₁H₄₂N₉O₆]⁺=636.3253). EA (C₃₁H₄₁N₉O₆·0.1FA·1.0H₂O, M_R=658.3): C 56.7 (56.4); H 6.6 (6.4); N 19.1 (18.8).

Synthesis of TD1160: In a pear-shape glass flask (100 mL), TD1116 (50 mg; 158 μmol; 2.0 equiv.) was dissolved in MeCN (20 mL) followed by addition of dried K₂CO₃ (11 mg; 80 μmol; 1.0 equiv.). Solution of TD558 (12 mg; 79 μmol; 1.0 equiv.) in MeCN (20 mL) was then added dropwise over the course of 2 h and the resulting suspension was stirred 7 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with mono alkylated intermediate were combined and directly lyophilized. Resulting solid (15.4 mg; ≤36 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (25 mg; 181 μmol; ≥5.0 equiv.). Solution of TD1130 (15 mg; 53 μmol; ≥1.5 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 7 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with methyl protected product were joined and directly lyophilized. Residue was re-dissolved in a mixture of MeOH (2 mL) and H₂O (1 mL) followed by addition of solid LiOH H₂O (15 mg; 360 μmol; ≥10 equiv.). The resulting mixture was stirred 15 min at RT, quenched with FA (15 μL) and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white solid. Yield: 1.7 mg (<5%; 3 steps; based on TD558). ESI-HRMS: 650.3407 [M+H]⁺ (theor. [C₃₂H₄₄N₉O₆]⁺=650.3409).

Synthesis of TD1176: In a glass vial (4 mL), TD635 (43.5 mg; 84.4 μmol; 1.1 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (42.5 mg; 308 μmol; 4.0 equiv.). Solution of TD1163 (17.3 mg; 76.7 μmol; 1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 2 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 43.6 mg (80%; 2 steps; based on TD1163). NMR (D₂O, pD ˜7): ¹H δ_H 2.74-3.62 (mc, CH₂—CO, CH₃, m, 16+4+6H); 3.70 (C≡CH, s, 1H); 3.76 (CH₂-arom., bs, 2H); 3.84 (CH₂-arom., bs, 2H); ˜4.7-4.8 (CH₂—N₃, obscured by HOD signal); 6.85 (arom., bs, 1H); 7.02 (arom., bs, 1H); 7.64 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., bt, 1H, ³J_HH=8); 7.94 (arom., bd, 1H, ³J_HH=8). ESI-HRMS: 593.3310 [M+H]⁺ (theor. [C₂₉H₄₁N₁₀O₄]⁺=593.3307). EA (C₂₉H₄₀N₁₀O₄·0.8FA·4.4H₂O, M_R=708.8): C 50.5 (50.8); H 7.2 (7.1); N 19.8 (19.5).

Synthesis of TD647: In a pear-shape glass flask (50 mL), TD635 (375 mg; 727 μmol; 1.0 equiv.) was dissolved in dry MeCN (20 mL) followed by addition of dried K₂CO₃ (300 mg; 2.17 mmol; 3.0 equiv.). Solution of TD566 (189 mg; 731 μmol; 1.0 equiv.) in dry MeCN (5 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 342 mg (72%; 2 steps; based on TD635). NMR (D₂O, pD ˜4): ¹H δ_H 2.70-3.59 (mc, CH₂—CO, m, 16+4H); 3.66 (CH₂-arom., bs, 2H); 3.69 (C≡CH, s, 1H); 3.90 (CH₂-arom., bs, 2H); 4.64 (CH₂—N₃, s, 2H); 7.46-7.60 (Ph, arom., m, 3+1H); 7.64 (arom., dd, 1H, ³J_HH=8, J_HH=2); 7.68 (arom., t, 1H, ³J_HH=8); 7.69 (arom., d, 1H, ⁴J_HH=2); 7.79-7.88 (Ph, m, 2H); 8.28 (arom., d, 1H, ⁴J_HH=2). ¹³C{¹H} δ_C 48.2 (mc, s); 48.3 (mc, s); 51.2 (mc, s); 51.3 (mc, s); 54.7 (CH₂—N₃, s); 56.4 (CH₂—CO, s); 57.8 (CH₂-arom., s); 59.1 (CH₂-arom., s); 80.3 and 82.4 (C≡CH; 2×s); 121.9 (arom., s); 124.4 (arom., s); 125.6 (arom., s); 128.2 (Ph, s); 128.5 (Ph, s); 130.0 (Ph, s); 130.8 (arom., s); 137.7 (Ph, s); 140.3 (arom., s); 141.2 (arom., s); 153.6 (arom., s); 155.4 (arom., bs); 156.2 (arom., s); 157.6 (arom., s); 168.7 (CO, s). ESI-HRMS: 626.3195 [M+H]⁺ (theor. [C₃₃H₄₀N₉O₄]⁺=626.3198). EA (C₃₃H₃₉N₉O₄·0.2FA·0.9H₂O, M_R=651.2): C 61.2 (61.6); H 6.4 (6.1); N 19.4 (19.1).

Synthesis of TD722: In a glass vial (20 mL), TD539 (350 mg; 543 μmol; 1.0 equiv.) was dissolved in MeCN (15 mL) followed by (addition of dried K₂CO₃ (375 mg; 2.72 mmol; 5.0 equiv.). Solution of TD566 (140 mg; 541 μmol; 1.0 equiv.) in MeCN (3 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl/Boc protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (5 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were Joined and directly lyophilized to give product in the form of trifluoroacetate salt as slightly yellow solid. Yield: 295 mg (69%; 2 steps; based on TD566). NMR (D₂O, pD ˜7): ¹H δ_H 2.74-3.64 (mc, CH₂—CO, m, 16+4H); 3.72 (CH₂-arom., bs, 2H); 3.98 (CH₂-arom., bs, 2H); 4.10 (CH₂—C≡C, s, 2H); 4.65 (CH₂—N₃, s, 2H); 7.47-7.69 (Ph, arom., m, 3+3H); 7.72 (arom., d, 1H, ⁴J_HH=2); 7.85-7.96 (Ph, m, 2H); 8.41 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 655.3460 [M+H]⁺ (theor. [C₃₄H₄₃N₁₀O₄]⁺=655.3463). EA (C₃₄H₄₂N₁₀O₄·0.7TFA·2.0H₂O, M_R=770.6): C 55.2 (54.9); H 6.1 (5.8); N 18.2 (18.3); F 5.2 (5.3).

Synthesis of TD1054: In a glass vial (4 mL), TD663 (30.0 mg; 45.3 μmol; 1.0 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (37.5 mg; 271 μmol; 5.0 equiv.). Solution of freshly prepared and isolated TD1050 (≤65.3 μmol; ≤1.5 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 3 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl/Boc protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of mixed trifluoroacetate/formate salt as colourless solid. Yield: 23.0 mg (65%; 2 steps; based on TD663). NMR (D₂O, pD ˜8): ¹H δ_H 1.72 (CH₃, s, 6H); 2.67-3.61 (mc, CH₂—CO, m, 16+4H); 3.70 (CH₂-arom., bs, 2H); 3.97 (CH₂-arom., bs, 2H); 4.64 (CH₂—N₃, s, 2H); 7.45-7.67 (Ph, arom., m, 3+3H); 7.72 (arom., d, 1H, ⁴J_HH=2); 7.86-7.93 (Ph, m, 2H); 8.40 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 683.3775 [M+H]⁺ (theor. [C₃₆H₄₇N₁₀O₄]⁺=683.3776). EA (C₃₆H₄₆N₁₀O₄·0.3TFA·0.8FA·2.3H₂O, M_R=777.3): C 57.8 (58.0); H 6.5 (6.5); N 18.0 (17.7).

Synthesis of TD1105: In a glass vial (4 mL), TD711 (101 mg; 185 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (102 mg; 738 μmol; 4.0 equiv.). Solution of freshly prepared and isolated TD1050 (≤222 μmol; ≤1.2 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 24 h at 40° C. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with tert-butyl/Boc protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with fully deprotected intermediate were joined and directly lyophilized. The resulting solid was dissolved in a mixture of H₂O (6 mL), MeCN (6 mL) and THF (2 mL) followed by addition of Boc₂O (2.0 M in dry THF; 315 μL; 630 μmol; ≥3.4 equiv.) and NaHCO₃ (210 mg; 2.50 mmol; ≥13.5 equiv.) The resulting mixture was stirred 2 d at RT after which another portion of Boc₂O (2.0 M in dry THF; 315 μL; 630 μmol; ≥3.4 equiv.) was added. The mixture was further stirred 16 h at RT. Mixture was evaporated to dryness and the residue was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were joined to give product in nearly zwitterionic form as white fluffy solid. Yield: 36.8 mg (27%; 3 steps; based on TD711). NMR (D₂O, pD ˜7): ¹H δ_H 1.47 (CH₃, s, 9H); 1.65 (CH₃, s, 6H); 2.85-3.65 (mc, CH₂—CO, m, 16+4H); 3.91 (CH₂-arom., bs, 2H); 3.95 (CH₂-arom., bs, 2H); 4.59 (CH₂—N₃, s, 2H); 7.51 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.59 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.89-8.05 (arom., m, 4H). ESI-HRMS: 707.3988 [M+H]⁺ (theor. [C₃₅H₅₁N₁₀O₆]⁺=707.3988). EA (C₃₅H₅₀N₁₀O₆·0.1FA·2.0H₂O, M_R=747.5): C 56.4 (56.7); H 7.3 (7.0); N 18.7 (18.5).

Synthesis of TD1127: In a glass vial (20 mL), TD1118 (56.9 mg; 81.4 μmol; 1.0 equiv.) was dissolved in MeCN (2 mL) followed by addition of dried K₂CO₃ (45.0 mg; 326 μmol; 4.0 equiv.) and TD406 (16.0 mg; 87.6 μmol; 1.1 equiv.) in MeCN (1 mL). The resulting suspension was stirred 16 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl/Boc protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of mixed trifluoroacetate/formate salt as colourless solid. Yield: 49.0 mg (71%; 2 steps; based on TD1118). NMR (D₂O, pD ˜7): ¹H δ_H 1.96-2.11 (CH₂, m, 2H); 2.14-2.29 (CH₂, m, 2H); 2.86-3.63 (mc, CH₂—CO, CH₂, CH, m, 16+4+4+1H); 3.90 (CH₂-arom., bs, 2H); 3.94 (CH₂-arom., bs, 2H); 4.59 (CH₂—N₃, s, 2H); 7.49-7.55 (arom., m, 1H); 7.60 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=2); 7.92-8.04 (arom., m, 4H). ESI-HRMS: 633.3612 [M+H]⁺ (theor. [C₃₂H₄₅N₁₀O₄]⁺=633.3620). EA (C₃₂H₄₄N₁₀O₄·1.8TFA·0.1FA, M_R=878.6): C 50.9 (50.7); H 5.5 (5.9); N 16.6 (16.9).

Synthesis of TD742: In a glass vial (20 mL), TD635 (90 mg; 163 μmol; 1.1 equiv.) was dissolved in MeCN (6 mL) followed by addition of dried K₂CO₃ (85 mg; 616 μmol; 4.0 equiv.). Solution of TD733 (55 mg; 153 μmol; 1.0 equiv.) in MeCN (2 mL) was then added and the resulting suspension was stirred 18 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 87 mg (80%; 2 steps; based on TD733). NMR (D₂O, pD ˜4): ¹H δ_H 2.76-3.64 (mc, CH₂—CO, m, 16+4H); 3.69 (C≡CH, s, 1H); 3.72 (CH₂-arom., bs, 2H); 3.99 (CH₂-arom., bs, 2H); 4.77 (CH₂—N₃, s, 2H); 7.54-7.70 (arom., m, 3H); 7.85 (arom., d, 1H, ⁴J_HH=2); 7.96 (arom., d, 2H, ³J_HH=8); 8.11 (arom., d, 2H, ³J_HH=8); 8.38 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 670.3094 [M+H]⁺ (theor. [C₃₄H₄₀N₉O₆]⁺=670.3096). EA (C₃₄H₄₀N₉O₆·0.2FA·1.6H₂O, M_R=707.8): C 58.0 (58.4); H 6.1 (5.9); N 17.8 (17.5).

Synthesis of TD744: In a glass vial (20 mL), TD539 (80 mg; 124 μmol; 1.1 equiv.) was dissolved in MeCN (3 mL) followed by addition of dried K₂CO₃ (65 mg; 471 μmol; 4.0 equiv.). Solution of TD733 (42 mg; 117 μmol; 1.0 equiv.) in MeCN (3 mL) was then added and the resulting suspension was stirred 24 h at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of mixed trifluoroacetate/formate salt as off white fluffy solid. Yield: 44 mg (45%; 2 steps; based on TD733). NMR (D₂O, pD ˜4): ¹H δ_H 2.71-3.64 (mc, CH₂—CO, m, 16+4H); 3.70 (CH₂-arom., bs, 2H); 3.98 (CH₂-arom., bs, 2H); 4.12 (CH₂—C≡C, s, 2H); 4.70 (CH₂—N₃, s, 2H); 7.50-7.59 (arom., m, 2H); 7.63 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.78 (arom., d, 1H, ⁴J_HH=2); 7.95 (arom., d, 2H, ³J_HH=9); 8.07 (arom., d, 2H, ³J_HH=9); 8.42 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 699.3358 [M+H]⁺ (theor. [C₃₅H₄₃N₁₀O₆]⁺=699.3362). EA (C₃₅H₄₂N₁₀O₆·1.0TFA·1.3H₂O, M_R=836.2): C 53.1 (52.8); H 5.5 (5.8); N 16.8 (16.9). Synthesis of TD750: In a glass vial (2 mL), TD744·1.0TFA·1.3H₂O (1.5 mg; ˜1.8 μmol; 1.0 equiv.) was dissolved in aq. Borate/NaOH buffer (200 mM; pH 9.0; 900 μL; 180 mmol; ˜100 equiv.). followed by addition of freshly prepared solution of FmocCl (0.6 mg; ˜2.3 μmol; 1.3 equiv.) in MeCN (900 μL). The resulting clear solution was stirred 2 h at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 0.8 mg (≤48% assuming M·0.2FA·xH₂O; M_R=930.2; 1 step; based on TD744·1.0TFA·1.3H₂O). ESI-HRMS: 921.4044 [M+H]⁺ (theor. [C₅₀H₅₃N₁₀O₈]⁺=921.4042).

Synthesis of TD779: In a glass vial (4 mL), TD647·0.2FA·0.9H₂O (10 mg; 15 μmol; 1.0 equiv.) and Ammonium chloride (2 mg; 38 μmol; 2.5 equiv.) were dissolved in DMSO (2 mL) followed by addition of DIPEA (22 μL; 126 μmol; 8.2 equiv.) and solid HATU (18 mg; 47 μmol; 3.1 equiv.). The resulting yellow solution was stirred 15 min at RT. Mixture was then quenched with FA (6 μL; 169 μmol; 10 equiv.) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 7 mg (≤73% assuming M·0.1FA·xH₂O; M_R=628.4; 1 step; based on TD6470.2FA·9H₂O). NMR (D₂O+FA, pD ˜3): ¹H δ_H 2.83-3.74 (mc, CH₂—CO, bm, 16+4H); 3.65 (C≡CH, s, 1H); 4.13-4.68 (CH₂-arom., bm, 4H); 4.69 (CH₂—N₃, s, 2H); 7.52-7.66 (Ph, arom., m, 3+1H); 7.71 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.80-7.88 (Ph, m, 2H); 7.90 (arom., d, 1H, ⁴J_HH=2); 7.91 (arom., t, 1H, ³J_HH=8); 8.00 (arom., bs, 1H). ESI-HRMS: 624.3503 [M+H]⁺ (theor. [C₃₃H₄₂N₁O₂]⁺=624.3504).

Synthesis of TD778: In a glass vial (4 mL), TD647·0.2FA·0.9H₂O (12 mg; 18 μmol; 1.0 equiv.) and Glycine tert-butyl ester hydrochloride (8 mg; 48 μmol; 2.6 equiv.) were dissolved in DMSO (2 mL) followed by addition of DIPEA (26 μL; 149 μmol; 8.1 equiv.) and solid HATU (21 mg; 55 μmol; 3.0 equiv.). The resulting yellow solution was stirred 20 min at RT. Mixture was then quenched with FA (7 μL; 186 μmol; 10 equiv.) and directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 9 mg (62%; 2 steps; based on TD647·0.2FA·9H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 2.83-3.93 (mc, CH₂—CO, C—CH, bm, 16+8+1H); 4.35-4.69 (CH₂-arom., CH₂—N₃., bm, 4+2H); 7.49 (arom., d, 1H, ³J_HH=8); 7.56-7.73 (Ph, arom., m, 3+1H); 7.75-7.92 (Ph, arom., m, 2+2H); 8.06 (arom., s, 1H). ESI-HRMS: 738.3471 [M−H]⁻ (theor. [C₃₇H₄₄N₁O₆]⁻=738.3482). EA (C₃₇H₄₅N₁₁O₆·0.1FA·2.4H₂O, M_R=787.7): C 56.6 (55.9); H 6.4 (5.8); N 19.6 (20.3).

Synthesis of TD1408: In a glass vial (25 mL), TD635 (51 mg; 99 μmol; 1.1 equiv.) was dissolved in MeCN (1 mL) followed by addition of dried K₂CO₃ (54 mg; 391 μmol; 4.4 equiv.). Solution of TD1406 (17.5 mg; 89 μmol; 1.0 equiv.) in MeCN (1 mL) was then added and the resulting suspension was stirred 16 h at 40° C. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 41.7 mg (77%; 2 steps; based on TD1406). NMR (D₂O, pD ˜7): ¹H δ_H 2.74-4.16 (mc, CH₂—CO, CH₂-arom., CH₂—CH₂—N₃, C—CH, m, 16+4+4+4+1H); 7.37-7.45 (arom., m, 1H); 7.65 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85-7.93 (arom., m, 2H); 7.96 (arom., t, 1H, ³J_HH=8); 8.06 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1). ESI-HRMS: 564.3044 [M+H]⁺ (theor. [C₂₈H₃₈N₉O₄]⁺=564.3041). EA (C₂₈H₃₇N₉O₄·0.1FA·2.4H₂O, M_R=611.5): C 55.2 (56.0); H 6.9 (6.7); N 20.6 (19.8).

Synthesis of TD1346: In a pear-shaped glass flask (25 mL), TD1345 (52.7 mg; 83 μmol; 1.0 equiv.) was dissolved in 60% aq. MeCN (2.7 mL) followed by addition of freshly prepared aq. LiOH (1.0 M; 830 μL; 830 μmol; 10 equiv.). Resulting solution was stirred at RT for 5 h. Mixture was quenched by addition of FA (31 μL; 822 μmol; 10 equiv.). The resulting solution was briefly concentrated to remove most of MeCN and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of free base as white fluffy solid. Yield: 35.4 mg (71%; 1 step; based on TD1345). NMR (D₂O, pD ˜7): ¹H δ_H 1.24-1.42 (CH₃, m, 6H); 2.44-3.81 (mc, CH₂-arom., C—CH, m, 16+4+1H); 4.41-4.53 (CH—CH₃, m, 2H); 4.56 (CH₂—N₃, s, 2H); 7.49 (arom., d, 1H, ³J_HH=8); 7.63 (arom., d, 1H, ³J_HH=8); 7.93 (arom., t, 1H, ³J_HH=8); 7.96 (arom., t, 1H, ³J_HH=8); 8.05 (arom., d, 1H, ³J_HH=8); 8.10 (arom., d, 1H, ³J_HH=8). ESI-HRMS: 578.3197 [M+H]⁺ (theor. [C₂₉H₄₀N₉O₄]⁺=578.3198). EA (C₂₉H₃₉N₉O₄ 1.2H₂O, M_R=599.3): C 58.1 (58.0); H 7.0 (6.5); N 21.0 (20.6).

Synthesis of TD1451: In a pear-shaped glass flask (25 mL), TD1449 (302 mg; 330 μmol; 1.0 equiv.) was dissolved in 60% aq. MeCN (17 mL) followed by addition of freshly prepared aq. LiOH (1.0 M; 3.3 mL; 3.3 mmol; 10 equiv.). Resulting solution was stirred at RT for 2 h. Mixture was briefly concentrated to remove most of MeCN and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in nearly zwitterionic form as white fluffy solid. Yield: 257 mg (87%; 1 step; based on TD1449). NMR (D₂O, pD ˜3): ¹H δ_H 1.37-1.60 (CH₃—C—O, CH₃—CH, m, 9+6H); 1.67 (CH₃—C—N, s, 6H); 2.66-4.30 (mc, CH₂-arom., CH—CH₃, m, 16+4+2H); 4.68 (CH₂—N₃, s, 2H); 7.80 (arom., s, 1H); 7.92 (arom., s, 1H); 7.98 (arom., s, 1H); 8.02 (arom., s, 1H). ¹⁹F δ_F −64.44 (s). ESI-HRMS: 847.4070 [M+H]⁺ (theor. [C₃₉H₅₄N₁₀O₈F₃]⁺=634.3824). EA (C₃₉H₅₃N₁₀O₈F₃·0.1FA·2.7H₂O, M_R=900.1): C 52.2 (53.1); H 6.6 (6.2); N 15.6 (15.5); 6.3 (5.4).

Synthesis of TD1504: In a glass vial (25 mL), TD1500 (11.9 mg; 18 μmol; 1.0 equiv.) was dissolved in MeCN (800 μL) and H₂O (550 μL) followed by addition of freshly prepared aq. LiOH (1.0 M; 263 μL; 263 μmol; 15 equiv.). Resulting solution was stirred at RT for 3 h. Mixture was quenched by addition of FA (8 μL; 212 μmol; 12 equiv.). The resulting solution was diluted with H₂O (2 mL) and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of free base as white fluffy solid. Yield: 8.9 mg (˜77% assuming M·2H₂O; M_R=657.7; 2 steps; based on TD1500). NMR (D₂O, pD ˜3): ¹H δ_H 1.28-1.45 (CH₃, m, 3H); 2.49-3.70 (mc, CH—CH₃, CH—CH₂, CH₂-arom., m, 16+1+3+4H); 3.76 (C≡CH, s, 1H); 4.35-4.51 (CH₂—N₃, m, 2H); 7.69 (arom., dd, 2H, ³J_HH=8, ⁴J_HH=1); 7.98 (arom., t, 1H, ³J_HH=8); 8.05-8.21 (arom., m, 3H). ESI-MS (LC-MS): 622.3 [M+H]⁺ (theor. [C₃₀H₄₀N₉O₆]⁺=622.3).

Example 5: Synthesis of Caged Macrocyclic Ligands (Bridged with a Triazole Group)

Synthesis of cz-TD425: Obtained as side product during synthesis of TD425 in nearly zwitterionic form as white fluffy solid. Yield: 3 mg (≤1% assuming M·0.1FA·xH₂O; M_R=609.9; 3 steps; based on 2-Chloro-N-(prop-2-yn-1-yl)acetamide). NMR (D₂O, pD ˜3): ¹H δ_H 2.52-5.20 (mc, CH₂—CO, CH₂—NH—CO—CH₂, CH₂-arom., bm, 16+4+4+2H); 6.24 (CH₂—N₃., bs, 2H); 7.56-7.72 (Ph, m, 3H); 7.88 (CH—N₃, s, 1H); 7.88-7.94 (Ph, m, 2H); 8.33 (arom., d, 1H, ⁴J_HH=2); 8.73 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 606.3143 [M+H]⁺ (theor. [C₃₀H₄₀N₉O₅]⁺=606.3147).

Synthesis of cz-TD556: Obtained as side product during synthesis of TD556 in the form of trifluoroacetate salt as white fluffy solid. Yield: 9 mg (˜2%; 2 steps; based on TD635). NMR (D₂O, pD ˜3): ¹H δ_H 2.54-4.06 (mc, CH₂—CO, bm, 16+4H); 4.59 (CH₂-arom., bs, 2H); 5.02 (CH₂-arom., bs, 2H); 5.86 (CH₂—N₃, bs, 2H); 7.67 (arom., bd, 1H, ³J_HH=8); 7.70 (arom., bd, 1H, ³J_HH=8); 7.83 (arom., bd, 1H, ³J_HH=8); 7.87 (arom., bd, 1H, ³J_HH=8); 8.14 (arom., bt, 1H, ³J_HH=8); 8.16 (CH—N₃, bs, 1H); 8.17 (arom., bt, 1H, ³J_HH=8). ESI-HRMS: 550.2889 [M+H]⁺ (theor. [C₂₇H₃₆N₉O₄]⁺=550.2885). EA (C₂₇H₃₅N₉O₄ 2.7TFA·5H₂O, M_R=866.4): C 44.9 (44.8); H 4.5 (4.8); N 14.5 (14.8).

Synthesis of cz-TD764: Obtained as side product during synthesis of TD764 in the form of trifluoroacetate salt as white fluffy solid. Yield: 9 mg (˜2%; 2 steps; based on TD635). NMR (D₂O, pD ˜3): ¹H δ_H 2.48-3.94 (mc, CH₂—CO, bm, 16+4H); 4.57 (CH₂-arom., bs, 2H); 5.00 (CH₂-arom., bs, 2H); 5.94 (CH₂—N₃, bs, 2H); 7.64 (arom., d, 1H, ³J_HH=8); 7.79 (arom., s, 1H); 7.84 (arom., d, 1H, ³J_HH=8); 7.92 (arom., s, 1H); 8.14 (arom., t, 1H, ³J_HH=8); 8.15 (CH—N₃, s, 1H). ESI-HRMS: 582.2344 [M−H]⁻ (theor. [C₂₇H₃₃N₉O₄Cl₁]=582.2350). EA (C₂₇H₃₄N₉O₄Cl₁·1.8TFA·3.3H₂O, M_R=848.7): C 43.3 (43.3); H 5.0 (4.5); N 14.9 (14.5); Cl 4.2 (4.2); F 12.1 (12.0).

Synthesis of cz-TD1063: Obtained as side product during synthesis of TD1113 in the form of trifluoroacetate salt as white fluffy solid. Yield: 1.7 mg. NMR (D₂O, pD ˜3): ¹H δ_H 2.57-3.84 (mc, CH₂—CO, m, 16+4H); 4.70 (CH₂-arom., s, 2H); 4.99 (CH₂-arom., bs, 2H); 6.03 (CH₂—N₃, bs, 2H); 7.65 (arom., d, 1H, ³J_HH=8); 7.86 (arom., d, 1H, ³J_HH=8); 8.05 (arom., s, 1H); 8.12-8.18 (arom., CH—N₃, m, 1+1H); 8.19 (arom., s, 1H). ¹⁹F δ_F −65.82 (s). NMR (˜0.5 mM cz-TD1063 in ˜50 mM MOPS/NaOH buffer in 10% H₂O, pH 7.0): ¹⁹F δ_F −65.66 (s; ΔH_1/2=4.6 Hz). ESI-HRMS: 618.2754 [M+H]⁺ (theor. [C₂₉H₃₅N₉O₄F₃]⁺=618.2759).

Synthesis of TD1188: In a glass vial (4 mL), TD711(70.0 mg; 128 μmol; 1.0 equiv.) was dissolved in MeCN (1.5 mL) followed by addition of dried K₂CO₃ (71 mg; 514 μmol; 4.0 equiv.). Solution of TD1178 (31 mg; 141 μmol; 1.1 equiv.) in MeCN (1.5 mL) was then added and the resulting suspension was stirred 7 d at RT. Solids were filtered off using syringe microfilter (PTFE) and filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with tert-butyl protected product were combined, evaporated to dryness and twice co-evaporated with MeOH to remove most of MeCN. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and twice co-evaporated with MeOH to remove most of TFA. Residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in zwitterionic form as white fluffy solid. Yield: 9.5 mg (10%; 2 steps; based on TD711). NMR (D₂O, pD ˜5): ¹H δ_H 2.11-4.00 (mc, CH₂—CO, bm, 16+4H); 4.52 (CH₂-arom., bs, 2H); 4.88-6.58 (CH₂-arom., CH₂—N₃, bm, 4H); 7.66 (arom., bd, 1H, ³J_HH=8); 7.68 (arom., d, 1H, ³J_HH=8); 7.75 (arom., bd, 1H, ³J_HH=8); 7.85 (arom., d, 1H, ³J_HH=8); 8.08 (arom., bt, 1H, ³J_HH=8); 8.16 (arom., t, 1H, ³J_HH=8). ¹⁹F δ_F −59.35 (s). ESI-HRMS: 618.2756 [M+H]⁺ (theor. [C₂₈H₃₅N₉O₄F₃]⁺=618.2759). EA (C₂₈H₃₄N₉O₄F₃·0.2TFA·0.4FA·4.3H₂O, M_R=736.3): C 47.0 (46.6); H 6.0 (5.6); N 17.1 (16.8); F 9.3 (10.1).

Synthesis of TD650: In a glass vial (40 mL), TD647·0.2FA·0.9H₂O (130 mg; 200 μmol; 1.0 equiv.) was dissolved in H₂O (20 mL) followed by addition aq. Citric acid (100 mM; 20 mL; 2.0 mmol; 10 equiv.) to reach pH 2.4. Resulting mixture was then stirred 2 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 109 mg (77%; 1 step; based on TD647·0.2FA·0.9H₂O). NMR (D₂O, pD ˜5, 95° C.): ¹H δ_H 2.69-3.63 (mc, CH₂—CO, m, 16+4H); 4.22 (CH₂-arom., s, 2H); 4.58 (CH₂-arom., s, 2H); 6.22 (CH₂—N₃, s, 2H); 7.61 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.60-7.67 (Ph, m, 3H); 7.83 (arom., s, 1H); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86-7.92 (Ph, m, 2H); 8.00 (arom., s, 1H); 8.11 (arom., t, 1H, ³J_HH=8); 8.21 (CH—N₃, s, 1H). ¹³C{¹H} δ_C 48.5 (mc, s); 49.9 (mc, s); 50.2 (mc, s); 50.4 (mc, s); 53.4 (CH₂—N₃, s); 55.6 (CH₂—CO, s); 57.8 (CH₂-arom., s); 59.2 (CH₂-arom., s); 122.6 (arom., s); 124.2 (arom., s); 125.4 (arom., s); 125.9 (arom., s); 127.8 (Ph, s); 129.9 (Ph, s); 130.7 (Ph, s); 134.5 (CH—N₃, s); 137.0 (Ph, s); 138.0 (arom., s); 139.9 (arom., s); 147.1 (arom., s); 152.3 (arom., bs); 153.6 (arom., bs); 153.8 (arom., bs); 156.8 (arom., s); 172.6 (CO, s). ESI-HRMS: 626.3200 [M+H]⁺ (theor. [C₃₃H₄₀N₉O₄]⁺=626.3198). EA (C₃₃H₃₉N₉O₄·0.9FA·2.0H₂O, M_R=703.2). C 57.9 (58.3); H 6.4 (5.9); N 17.9 (17.5).

Synthesis of TD871: In a glass vial (40 mL), TD647·1.3TFA (78.0 mg; 103 μmol; 1.0 equiv.) was dissolved in H₂O (34 mL) followed by addition aq. Borate/CsOH buffer (200 mM; pH 9.0; 6.0 mL; 1.2 mmol; ˜12 equiv.). Resulting mixture was then stirred 6 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 49.3 mg (70%; 1 step; based on TD647·1.3TFA). NMR (D₂O, pD ˜5, 95° C.): ¹H δ_H 2.93-3.56 (mc, CH₂—CO, m, 16+4H); 4.41 (CH₂-arom., s, 2H); 4.49 (CH₂-arom., s, 2H); 6.00 (CH₂—N₃, s, 2H); 7.54 (arom., dd, 1H, ³J_HH=7, ⁴J_HH=2); 7.56-7.66 (Ph, m, 3H); 7.77 (arom., d, 1H, ⁴J_HH=1); 7.79-7.87 (Ph, m, 2H); 7.94 (arom., d, 1H, ⁴J_HH=1); 8.05 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=2); 8.07 (arom., dd, 1H, ³J_HH=8, ³J_HH=7); 8.93 (CH—N₃, S, 1H). ¹³C{¹H} δ_C 50.0 (mc, s); 50.7 (mc, bs); 52.0 (mc, s); 52.3 (mc, s); 54.8 (CH₂—N₃, s); 56.6 (CH₂—CO, s); 59.9 (CH₂-arom., s); 60.2 (CH₂-arom., bs); 121.2 (arom., s); 121.7 (arom., s); 123.3 (arom., s); 124.5 (arom., s); 127.0 (CH—N₃, s); 127.7 (Ph, s); 129.9 (Ph, s); 130.5 (Ph, s); 137.1 (Ph, s); 140.2 (arom., s); 148.0 (arom., s); 150.3 (arom., s); 151.7 (arom., s); 152.5 (arom., bs); 154.9 (arom., s); 155.0 (arom., s); 174.4 (CO, s). ESI-HRMS: 626.3199 [M+H]⁺ (theor. [C₃₃H₄₀N₉O₄]⁺=626.3198). EA (C₃₃H₃₉N₉O₄·0.6FA·2.3H₂O, M_R=696.8): C 58.1 (57.9); H 6.5 (6.2); N 18.1 (18.2).

Example 6: Synthesis of Coordination Compounds

Synthesis of TD734: In a glass vial (20 mL), TD714·0.1FA·xH₂O (6 mg; ˜10 μmol; 1.0 equiv.) was dissolved in H₂O (4 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.00 mL; 500 μmol; ˜50 equiv.) and aq. LuCl₃ (100 mM; 110 μL; 11 μmol; ˜1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as a mixture of two diastereoisomer (˜11:1) in the form of formate salt as white fluffy solid. Yield: 5 mg (≤61% assuming [M]⁺[FA]⁻·xH₂O; M_R=803.6; 1 step; based on TD714·0.1FA·xH₂O). NMR (D₂O, pD ˜4, signals of major isomer): ¹H δ_H 2.50-3.82 (mc, CH₂—CO, CH₂—P, m, 16+2+1H); 3.85-4.00 (CH₂-arom., CH₂—P, m, 1+1H); 4.10 (CH₂-arom., d, 1H, ²J_HH=16); 4.23 (CH₂-arom., d, 1H, ²J_HH=15); 4.99 (CH₂-arom., d, 1H, ²J_HH=15); 5.53 (CH₂—N₃, d, 1H, ²J_HH=15); 7.56 (CH₂—N₃, d, 1H, ²J_HH=15); 7.67 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=2); 7.83 (CH—N₃, s, 1H); 7.98 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=8, ⁴J_HH=2); 7.18 (arom., t, 1H, ³J_HH=8); 8.20 (arom., t, 1H, ³J_HH=8); 8.35 (FA, s, 1H). ¹³C{¹H} δ_C 48.9 (mc, s); 51.3 (mc, s); 51.6 (CH₂—P, d, ¹J_CP=73); 52.0 (mc, s); 52.3 (mc, s); 53.4 (mc, s); 53.5 (CH₂—N₃, s); 53.6 (mc, s); 55.0 (mc, s); 56.3 (mc, s); 59.7 (CH₂-arom., s); 60.0 (CH₂-arom., s); 61.0 (CH₂—CO, s); 125.9 (arom., s); 127.6 (arom., s); 128.9 (arom., s); 130.4 (arom., s); 136.4 (CH—N₃, s); 138.7 (arom., s); 142.0 (arom., s); 142.9 (arom., s); 146.2 (arom., s); 156.8 (arom., s); 157.6 (arom., s); 158.6 (arom., s); 169.5 (FA, s); 178.2 (CO, s). ³¹P{¹H} δ_P 17.8 (s). ESI-HRMS: 758.1822 [M]⁺ (theor. [C₂₆H₃₄N₉O₅P₁Lu₁]⁺=758.1823).

Synthesis of TD925: In a glass vial (20 mL), TD921·4.6H₂O (6.1 mg; 7.4 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) and i-PrOH (1 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 400 μL; 200 μmol; 27 equiv.) and aq. GdCl₃ (100 mM; 95 μL; 9.5 μmol; 1.3 equiv.) and the mixture was stirred 7 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 2.5 mg (≤33% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1010.0; 1 step; based on TD921·4.6H₂O). ESI-HRMS: 897.2158 [M]⁺ (theor. [C₃₇H₄₃N₉O₄P₂Gd₁]⁺=897.2149).

Synthesis of TD560: In a glass vial (20 mL), TD556·0.1FA·1.6H₂O (39 mg; 69 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.40 mL; 1.70 mmol; 25 equiv.) and aq. EuCl₃ (100 mM; 745 μL; 75 μmol; 1.1 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 24 mg (43%; 1 step; based on TD556·0.1FA·1.6H₂O). ESI-HRMS: 700.1867 [M]⁺ (theor. [C₂₇H₃₃N₉O₄Eu₁]⁺=700.1862). EA ([C₂₇H₃₃N₉O₄Eu₁]⁺[FA]⁻·4.5H₂O, M_R=825.7): C 40.7 (40.7); H 5.2 (4.8); N 15.3 (15.0); Eu 18.4 (17.7).

Synthesis of TD561: In a glass vial (20 mL), TD556·0.1FA·1.6H₂O (40 mg; 69 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.40 mL; 1.70 mmol; 25 equiv.) and aq. GdCl₃ (100 mM; 745 μL; 75 μmol; 1.1 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 24 mg (42%; 1 step; based on TD556·0.1FA·1.6H₂O). ESI-HRMS: 705.1893 [M]⁺ (theor. [C₂₇H₃₃N₉O₄Gd₁]⁺=705.1891). EA ([C₂₇H₃₃N₉O₄Gd₁]⁺[FA]⁻·4.6H₂O, M_R=832.8): C 40.4 (40.8); H 5.2 (4.9); N 15.1 (15.5); Gd 18.9 (18.1).

Synthesis of TD562: In a glass vial (20 mL), TD556·0.1FA·1.6H₂O (40 mg; 69 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.40 mL; 1.70 mmol; 25 equiv.) and aq. TbCl₃ (100 mM; 745 μL; 75 μmol; 1.1 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 27 mg (47%; 1 step; based on TD556·0.1FA·1.6H₂O). ESI-HRMS: 706.1906 [M]⁺ (theor. [C₂₇H₃₃N₉O₄Tb₁]⁺=706.1903). EA ([C₂₇H₃₃N₉O₄Tb₁]⁺[FA]⁻·4.7H₂O, M_R=836.2): C 40.2 (40.5); H 5.2 (4.9); N 15.1 (14.7); Tb 19.0 (18.7).

Synthesis of TD1069: In a glass vial (20 mL), TD556·0.1FA·1.6H₂O (20.8 mg; 35.7 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.80 mL; 900 μmol; 25 equiv.) and aq. LuCl₃ (100 mM; 400 μL; 40.0 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 26.6 mg (82%; 1 step; based on TD556·0.1FA·1.6H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.64-3.82 (mc, CH₂—CO, m, 16+4H); 3.95 (CH₂-arom., d, 1H, ²J_HH=15); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.29 (CH₂-arom., d, 1H, ²J_HH=15); 4.85 (CH₂-arom., d, 1H, ²J_HH=16); 5.60 (CH₂—N₃, d, 1H, ²J_HH=15); 7.10 (CH₂—N₃, d, 1H, ²J_HH=15); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH—N₃, s, 1H); 8.02 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.25 (arom., t, 1+1H, ³J_HH=8). ESI-HRMS: 722.2060 [M]⁺ (theor. [C₂₇H₃₃N₉O₄Lu₁]⁺=722.2058). EA ([C₂₇H₃₃N₉O₄Lu₁]⁺[TFA]⁻·0.3TFA·2.4H₂O, M_R=913.0): C 38.9 (38.7); H 4.2 (3.8); N 13.8 (13.7); Lu 19.2 (16.5).

Synthesis of TD751: In a glass vial (20 mL), TD718·2.6H₂O (14 mg; 21 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) followed by addition aq. MES/NaOH buffer (500 mM; pH 5.2; 1.30 mL; 650 μmol; 31 equiv.) and aq. LuCl₃ (100 mM; 236 μL; 24 μmol; 1.1 equiv.) and the mixture was stirred 3 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 13 mg (65%; 1 step; based on TD718·2.6H₂O). NMR (D₂O, pD ˜6): ¹H δ_H 0.10 (CH₃, s, 9H); 2.61-3.83 (mc, CH₂—CO, m, 16+4H); 3.94 (CH₂-arom., d, 1H, ²J_HH=15); 4.24 (CH₂-arom., d, 1H, ²J_HH=16); 4.24 (CH₂-arom., d, 1H, ²J_HH=15); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.54 (CH₂—N₃, d, 1H, ²J_HH=15); 6.92 (CH₂—N₃, d, 1H, ²J_HH=15); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.75 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.98 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.22 (arom., t, 1H, ³J_HH=8); 8.26 (arom., t, 1H, ³J_HH=8); 8.45 (FA, s, 1H). ¹³C{¹H} δ_C-1.85 (CH₃, s); 48.4 (mc, s); 48.7 (mc, s); 50.7 (mc, s); 51.9 (mc, s); 52.0 (CH₂—N₃, s); 53.2 (mc, s); 53.8 (mc, s); 54.4 (mc, s); 55.5 (mc, s); 58.4 (CH₂—CO, s); 59.0 (CH₂-arom., s); 59.1 (CH₂-arom., s); 60.9 (CH₂—CO, s); 125.9 (arom., s); 126.7 (arom., s); 128.3 (arom., s); 130.4 (arom., s); 141.4 (arom., s); 142.3 (arom., s); 142.6 (arom., s); 146.3 (arom., s); 147.5 (arom., s); 155.1 (arom., s); 157.7 (arom., s); 158.7 (arom., s); 171.0 (FA, s); 176.8 (CO, s); 178.6 (CO, s). ESI-HRMS: 794.2445 [M]⁺ (theor. [C₃₀H₄₁N₉O₄Si₁Lu₁]⁺=794.2453). EA ([C₃₀H₄₁N₉O₄Si₁Lu₁]⁺[FA]⁻·6.6H₂O, M_R=958.7): C 38.8 (39.0); H 5.8 (5.3); N 13.1 (13.0); Si 2.9 (3.0); Lu 18.2 (17.4).

Synthesis of TD737: In a glass vial (20 mL), TD728·2.6H₂O (15 mg; 20 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.00 mL; 1.00 mmol; 50 equiv.) and aq. LuCl₃ (100 mM; 220 μL; 22 μmol; 1.1 equiv.) and the mixture was stirred 5 days at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 12 mg (58%; 1 step; based on TD728·2.6H₂O). NMR (D₂O, pD ˜5): δ_H 0.96 (i-Pr, d, 9H, ³J_HH=8); 0.99 (i-Pr, d, 9H, ³J_HH=8); 1.26 (i-Pr, hept, 3H, ³J_HH=8); 2.62-3.84 (mc, CH₂—CO, m, 16+4H); 4.05 (CH₂-arom., s, 2H); 4.29 (CH₂-arom., d, 1H, ²J_HH=17); 4.88 (CH₂-arom., d, 1H, ²J_HH=17); 5.43 (CH₂—N₃, d, 1H, ²J_HH=15); 6.74 (CH₂—N₃, d, 1H, ²J_HH=15); 7.67 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.94 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.20 (arom., t, 1H, ³J_HH=8); 8.22 (arom., t, 1H, ³J_HH=8); 8.43 (FA, s, 1H). ¹³C{¹H} δ_C 12.1 (i-Pr, s); 18.8 (i-Pr, 2×s); 47.9 (mc, bs); 50.0 (mc, bs); 50.4 (mc, bs); 52.2 (mc, bs); 53.0 (CH₂—N₃, s); 54.0 (mc, s); 55.2 (mc, s); 57.2 (mc, s); 57.6 (mc, s); 59.3 (CH₂—CO, s); 60.0 (CH₂-arom., s); 62.3 (CH₂-arom., bs); 64.0 (CH₂—CO, s); 126.1 (arom., s); 127.4 (arom., s); 128.9 (arom., s); 130.8 (arom., s); 141.6 (arom., s); 143.3 (arom., s); 143.8 (arom., s); 144.6 (arom., s); 147.1 (arom., s); 156.1 (arom., s); 158.4 (arom., s); 159.6 (arom., s); 171.5 (FA, s); 178.0 (CO, s); 179.1 (CO, s). ESI-HRMS: 878.3396 [M]⁺ (theor. [C₃₆H₅₃N₉O₄Si₁Lu₁]⁺=878.3392). EA ([C₃₆H₅₃N₉O₄Si₁Lu₁]⁺[FA]⁻·5.9H₂O, M_R=1030.2): C 43.1 (43.4); H 12.2 (11.8); N 12.2 (11.8); Si 2.7 (2.9); Lu 17.0 (16.9).

Synthesis of TD946: In a glass vial (20 mL), TD943·1.5H₂O (28.1 mg; 45.6 μmol; 1.0 equiv.) was dissolved

in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.00 mL; 1.50 mmol; 33 equiv.) and aq. LuCl₃ (100 mM; 540 μL; 54 μmol; 1.2 equiv.) and the mixture was stirred 3 days at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 32.6 mg (77%; 1 step; based on TD943·1.5H₂O). NMR (D₂O, pD ˜5): δ_H 0.69-0.94 (CH₂—CH, m, 2H); 0.94-1.07 (CH₂—CH, m, 2H); 1.65 (CH₂—CH, tt, 1H, ³J_HH=8, ³J_HH=5); 2.58-3.86 (mc, CH₂—CO, m, 16+4H); 3.97 (CH₂-arom., d, 1H, ²J_HH=15); 4.19 (CH₂-arom., d, 1H, ²J_HH=16); 4.29 (CH₂-arom., d, 1H, ²J_HH=15); 4.87 (CH₂-arom., d, 1H, ²J_HH=16); 5.53 (CH₂—N₃, d, 1H, ²J_HH=15); 6.99 (CH₂—N₃, d, 1H, ²J_HH=15); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.93 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.99 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.24 (arom., t, 1H, ³J_HH=8); 8.29 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 762.2375 [M]⁺ (theor. [C₃₀H₃₇N₉O₄Lu₁]⁺=762.2371). EA ([C₃₀H₃₇N₉O₄Lu₁]⁺[TFA]⁻·0.2TFA·1.8H₂O, M_R=930.8): C 41.8 (42.2); H 4.4 (4.2); N 13.5 (13.1); F 7.3 (7.0).

Synthesis of TD961: In a glass vial (20 mL), TD959·1.5H₂O (14.7 mg; 23.0 μmol; 1.0 equiv.) was dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.50 mL; 0.75 mmol; 33 equiv.) and aq. LuCl₃ (100 mM; 280 L; 28 μmol; 1.2 equiv.) and the mixture was stirred 3 days at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 20.1 mg (90%; 1 step; based on TD959·1.8H₂O). NMR (D₂O, pD ˜4): ^6H 1.18 (CH₃, s, 9H); 2.64-3.86 (mc, CH₂—CO, m, 16+4H); 4.01 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=15); 4.35 (CH₂-arom., d, 1H, ²J_HH=17); 4.87 (CH₂-arom., d, 1H, ²J_HH=17); 5.48 (CH₂—N₃, d, 1H, ²J_HH=15); 6.66 (CH₂—N₃, d, 1H, ²J_HH=15); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (arom., dd, 1H, ³J_HH=8, ⁴=1); 7.93 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.22 (arom., t, 1H, ³J_HH=8); 8.26 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 778.2685 [M]⁺ (theor. [C₃₁H₄₁N₉O₄Lu₁]⁺=778.2684). EA ([C₃1H₄1N₉O₄Lu₁]⁺[TFA]⁻·0.2TFA·3.0H₂O, M_R=968.5): C 41.4 (41.5); H 4.9 (4.6); N 13.0 (12.7); F 7.1(7.4).

Synthesis of TD951: In a glass vial (20 mL), TD944·1.5H₂O (14.4 mg; 22.1 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.20 mL; 600 μmol; 27 equiv.) and aq. LuCl₃ (100 mM; 265 μL; 26.5 μmol; 1.2 equiv.) and the mixture was stirred 4 days at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 17.4 mg (80%; 1 step; based on TD944·1.5H₂O). NMR (D₂O, pD ˜2): δ_H 2.69-3.88 (mc, CH₂—CO, m, 16+4H); 3.97 (CH₂-arom., d, 1H, ²J_HH=15); 4.16-4.36 (CH₂-arom., m, 2H); 4.88 (CH₂-arom., d, 1H, ²J_HH17); 5.51 (CH₂—N₃, d, 1H, ²J_HH=15); 6.97 (CH₂—N₃, d, 1H, ²J_HH=15); 7.16-7.25 (Ph, m, 2H); 7.28-7.41 (Ph, m, 3H); 7.49 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.03 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.06 (arom., t, 1H, ³J_HH=8); 8.25 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 798.2379 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Lu₁]⁺=798.2371). EA ([C₃₃H₃₇N₉O₄Lu₁]⁺[TFA]⁻·0.2TFA·3.0H₂O, M_R=988.5): C 43.0 (43.0); H 4.4 (4.3); N 12.8 (12.6); F 6.9 (6.9).

Synthesis of TD994: In a glass vial (20 mL), TD992·0.3FA·1.9H₂O (41.6 mg; 56.8 μmol; 1.0 equiv.) was

dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.85 mL; 1.43 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 625 μL; 62.5 μmol; 1.1 equiv.) and the mixture was stirred 8 days at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 52.3 mg (86%; 1 step; based on TD992·0.3FA·1.9H₂O). NMR (D₂O, pD ˜4): δ_H 1.52-1.78 (Adm., m, 9H); 1.80-1.95 (Adm., m, 6H); 2.60-3.83 (mc, CH₂—CO, m, 16+4H); 3.99 (CH₂-arom., d, 1H, ²J_HH=15); 4.11 (CH₂-arom., d, 1H, ²J_HH=15); 4.33 (CH₂-arom., d, 1H, ²J_HH=17); 4.84 (CH₂-arom., d, 1H, ²J_HH=17); 5.43 (CH₂—N₃, d, 1H, ²J_HH=15); 6.58 (CH₂—N₃, d, 1H, ²J_HH=15); 7.66 (arom., d, 1H, ³J_HH=8); 7.80 (arom., d, 1H, ³J_HH=8); 7.88-7.92 (arom., m, 2H); 8.18 (arom., t, 1H, ³J_HH=8); 8.22 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 856.3154 [M]⁺ (theor. [C₃₇H₄₇N₉O₄Lu₁]⁺=856.3153). EA ([C₃₇H₄₇N₉O₄Lu₁]⁺[TFA]⁻·0.4TFA·3.0H₂O, M_R=1069.4): C 44.7 (44.3); H 5.0 (4.6); N 11.8 (11.5); F 7.5 (7.4); Lu 16.4 (14.0).

Synthesis of TD1221: In a glass vial (20 mL), TD1204·0.3FA·2.7H₂O (22.5 mg; 30.5 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.57 mL; 785 μmol; 26 equiv.) and aq. LuCl₃ (100 mM; 375 μL; 37.5 μmol; 1.2 equiv.) and the mixture was stirred 24 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 24.5 mg (74%; 1 step; based on TD1204·0.3FA·2.7H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.59-3.83 (mc, CH₂—CO, m, 16+4H); 3.95 (CH₂-arom., d, 1H, ²J_HH=15); 4.23 (CH₂-arom., d, 1H, ²J_HH=17); 4.27 (CH₂-arom., d, 1H, ²J_HH=15); 4.85 (CH₂-arom., d, 1H, ²J_HH=17); 5.62 (CH₂—N₃, d, 1H, ²J_HH=15); 7.01 (CH₂—N₃, d, 1H, ²J_HH=15); 7.72 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (arom., d, 1H, ⁴J_HH=2); 7.90 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.97 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.23 (arom., t, 1H, ³J_HH=8); 8.29 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 848.1020 [M]⁺ (theor. [C₂₇H₃₂N₉O₄I₁Lu₁]⁺=848.1024). EA ([C₂₇H₃₂N₉O₄I₁Lu₁]⁺[TFA]⁻·0.5TFA·4.1H₂O, M_R=1092.3): C 33.0 (33.8); H 3.8 (3.6); N 11.5 (11.8); I 11.6 (10.9); F 7.8 (7.0).

Synthesis of TD782: In a glass vial (40 mL), TD764·0.7TFA·1.7H₂O (190 mg; 274 μmol; 1.0 equiv.) was dissolved in H₂O (21 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 15.4 mL; 7.70 mmol; 28 equiv.) and aq. LuCl₃ (100 mM; 3.30 mL; 330 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 224 mg (85%; 1 step; based on TD764·0.7TFA·1.7H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.61-3.84 (mc, CH₂—CO, m, 16+4H); 3.94 (CH₂-arom., d, 1H, ²J_HH=15); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.29 (CH₂-arom., d, 1H, ²J_HH=15); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.58 (CH₂—N₃, d, 1H, ²J_HH=15); 7.10 (CH₂—N₃, d, 1H, ²J_HH=15); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., d, 1H, ⁴J_HH=2); 7.85 (arom., dd, 1H, ³J_HH=8, ^4HJ_HH=1); 7.88 (CH—N₃, s, 1H); 8.13 (arom., d, 1H, ⁴J_HH=2); 8.24 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 756.1664 [M]⁺ (theor. [C₂₇H₃₂N₉O₄Cl₁Lu₁]⁺=756.1668). EA ([C₂₇H₃₂N₉O₄Cl₁Lu₁]⁺[TFA]⁻·5.1H₂O, M_R=961.9): C 36.2 (36.4); H 4.4 (4.0); N 13.1 (12.9); Cl 3.7 (3.7); F 5.9 (6.4); Lu 18.2 (16.8).

Synthesis of TD819: Glass vial (4 mL) was charged with [TD782]⁺[TFA]⁻·5.1H₂O (10.0 mg; 10.4 μmol; 1.0 equiv.), 3-borono-5-nitrobenzoic acid (4.4 mg; 21 μmol; 2.0 equiv.) and XPhos Pd G2 (0.5 mg; ˜0.6 μmol; 6 mol %) and was then three times secured with argon. Under constant flow of argon was then added dry DMF (420 μL) through septum followed by addition of freshly prepared (and briefly washed with argon prior addition) aq. solution of K₃PO₄·H₂O (326 mM; 160 μL; 52 μmol; 5.0 equiv.). The mixture was then stirred 16 h under septum (but without external argon) at 80° C. Resulting heterogenous mixture was diluted with H₂O (2 mL) and the resulting slightly opalescent pale-yellow solution was filtered through syringe microfilter (RC). Filtrate was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 10 mg (≤96% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1000.7; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.66-3.84 (mc, CH₂—CO, m, 16+4H); 4.07 (CH₂-arom., d, 1H, ²J_HH=15); 4.17 (CH₂-arom., d, 1H, ²J_HH=16); 4.39 (CH₂-arom., d, 1H, ²J_HH=15); 4.87 (CH₂-arom., d, 1H, ²J_HH=15); 5.72 (CH₂—N₃, d, 1H, ²J_HH=15); 7.19 (CH₂—N₃, d, 1H, ²J_HH15); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 8.14 (arom., d, 1H, ⁴J_HH=2); 8.26 (arom., t, 1H, ³J_HH=8); 8.45 (arom., d, 1H, ⁴J_HH=2); 8.82 (arom., dm, 1H, ⁴J_HH=2); 8.92 (arom., dd, 1H, ⁴J_HH=2, ⁴J_HH=1); 8.97 (arom., dm, 1H, ⁴J_HH=2). ESI-HRMS: 887.2121 [M]⁺ (theor. [C₃₄H₃₆N₁₀O₈Lu₁]⁺=887.2120).

Synthesis of TD891: Glass vial (4 mL) was charged with [TD782]⁺[TFA]⁻·5.1H₂O (15.0 mg; 15.6 μmol; 1.0 equiv.), 2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)acetic acid (8.0 mg; 30.5 μmol; 2.0 equiv.) and XPhos Pd G2 (0.7 mg; ˜0.9 μmol; 6 mol %) and was then three times secured with argon. Under constant flow of argon was then added dry DMF (600 μL) through septum followed by addition of freshly prepared (and briefly washed with argon prior addition) aq. solution of K₃PO₄·H₂O (391 mM; 200 μL; 78 μmol; 5.0 equiv.). The mixture was then stirred 16 h under septum (but without external argon) at 80° C. Resulting heterogenous mixture was diluted with H₂O (2 mL) and the resulting slightly opalescent pale-yellow solution was filtered through syringe microfilter (RC). Filtrate was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 7.2 mg (41%; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.60-3.82 (mc, CH₂—CO, m, 16+4H); 3.86 (OC—CH₂-arom., s, 2H); 3.99 (CH₂-arom., d, 1H, ²J_HH=15); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.32 (CH₂-arom., d, 1H, ²J_HH=15); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.65 (CH₂—N₃, d, 1H, ²J_HH=15); 7.13 (CH₂—N₃, d, 1H, ²J_HH=15); 7.54 (arom., dm, 2H, ³J_HH=8); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 7.92 (arom., dm, 2H, ³J_HH=8); 7.99 (arom., d, 1H, ⁴J_HH=1); 8.25 (arom., t, 1H, ³J_HH=8); 8.30 (arom., d, 1H, ⁴J_HH=1). ESI-HRMS: 856.2418 [M]⁺ (theor. [C₃₅H₃₉N₉O₆Lu₁]⁺-856.2426). EA ([C₃₅H₃₉N₉O₆Cl₁Lu₁]⁺[TFA]⁻·0.7TFA·4.6H₂O, M_R=1132.4): C 40.7 (40.6); H 4.4 (4.3); N 11.1 (11.3).

Synthesis of TD891-OH: TD891-OH was obtained (in the form of trifluoroacetate salt as white fluffy solid) as by-product during synthesis TD891. Yield: 5.7 mg. NMR (D₂O, pD ˜3): ¹H δ_H 2.60-3.83 (mc, CH₂—CO, CH₂-arom., m, 16+4+1H); 4.13 (CH₂-arom., d, 1H, ²J_HH=16); 4.20 (CH₂-arom., d, 1H, ²J_HH=15); 4.82 (CH₂-arom., d, 1H, ²J_HH=16); 5.43 (CH₂—N₃, d, 1H, ²J_HH=15); 6.97 (CH₂—N₃, d, 1H, ²J_HH=15); 7.09 (arom., d, 1H, ⁴J_HH=2); 7.40 (arom., d, 1H, ⁴J_HH=2); 7.79 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (CH—N₃, s, 1H); 8.23 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 738.2003 [M]⁺ (theor. [C₂₇H₃₃N₉O₈Lu₁]⁺=738.2007).

Synthesis of TD786: In a glass vial (4 mL), [TD782]⁺[TFA]⁻·5.1H₂O (37 mg; 38 μmol; 1.0 equiv.) was dissolved in DMSO (3 mL) followed by addition solid NaN₃ (54 mg; 831 μmol; 20 equiv.) and the mixture was stirred 2 h at 80° C. Mixture was then concentrated to remove most of DMSO. Residue was dissolved in H₂O and lyophilized. Crude product was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 21 mg (55%; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜4): ¹H δ_H 2.62-3.81 (mc, CH₂—CO, m, 16+4H); 3.87 (CH₂-arom., d, 1H, ²J_HH=15); 4.14 (CH₂-arom., d, 1H, ²J_HH=16); 4.25 (CH₂-arom., d, 1H, ²J_HH=15); 4.83 (CH₂-arom., d, 1H, ²J_HH=16); 5.52 (CH₂—N₃, d, 1H, ²J_HH=15); 7.05 (CH₂—N₃, d, 1H, ²J_HH=15); 7.38 (arom., d, 1H, ⁴J_HH=2); 7.71 (arom., d, 1H, ⁴J_HH=2); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH N₃, s, 1H); 8.24 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 763.2075 [M]⁺ (theor. [C₂₇H₃₂N₁₂O₄Lu₁]⁺=763.2072). EA ([C₂₇H₃₂N₁₂O₄Lu₁]⁺[TFA]⁻·0.2TFA·5.2H₂O, M_R=993.0): C 35.6 (35.6); H 4.3 (4.0); N 16.9 (16.6); F 6.9 (6.8).

Synthesis of TD787: Obtained as side product during synthesis of TD786 in the form of trifluoroacetate salt as white fluffy solid. Yield: 5 mg (˜10%; 1 step; based on TD782·5.1H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.59-3.79 (mc, CH₂—CO, CH₂-arom., m, 16+4+1H); 4.02-4.19 (CH₂-arom., m, 2H); 4.25 (CH₂-arom., d, 1H, ²J_HH=15); 4.79 (CH₂-arom., d, 1H, ²J_HH=15); 5.27 (CH₂—N₃, d, 1H, ²J_HH=15); 6.74 (arom., d, 1H, ⁴J_HH=2); 6.83 (CH₂—N₃, d, 1H, ²J_HH=15); 7.03 (arom., d, 1H, ⁴J_HH=2); 7.78 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1) 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (CH N₃, s, 1H); 8.22 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 737.2165 [M]⁺ (theor. [C₂₇H₃₄N₁₀O₄Lu₁]⁺=737.2167).

Synthesis of TD830: In a glass vial (20 mL), TD764·0.7TFA·1.7H₂O (60 mg; 86 μmol; 1.0 equiv.) was dissolved in H₂O (5 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 5.0 mL; 2.50 mmol; 29 equiv.). and freshly prepared aq. ¹⁷⁶YbCl₃ (˜90 μmol; ˜1.0 eq.; obtained by dissolving 18.1 mg of ¹⁷⁶Yb₂O in 0.5 mL of 6 M HCl at 80° C. for several hours, followed by evaporation of the acid and adding 10 mL of H₂O to the residue). Mixture was then stirred 6 h at 80° C. after which was filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 71 mg (≤94% assuming [M]⁺[TFA]⁻·xH₂O; M_R=871.0; 1 step; based on TD764·0.7TFA·1.7H₂O). ESI-HRMS: 757.1680 [M]⁺ (theor. [C₂₇H₃₂N₉O₄Cl₁¹⁷⁶Yb₁]⁺=757.1686).

Synthesis of TD836: In a glass vial (4 mL), [TD830]⁺[TFA]⁻·xH₂O (12.1 mg; ˜14 μmol; 1.0 equiv.) was dissolved in DMSO (500 μL) followed by addition solid NaN₃ (9.0 mg; 138 μmol; ˜10 equiv.) and the mixture was stirred 30 min at 80° C. Mixture was then diluted with H₂O (3 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 9.9 mg (≤81% assuming [M]⁺[TFA]⁻·xH₂O; M_R=877.6; 1 step; based on [TD830]⁺[TFA]⁻·xH₂O). ESI-HRMS: 764.2085 [M]⁺ (theor. [C₂₇H₃₂N₁₂O₄¹⁷⁶Yb₁]⁺=764.2090).

Synthesis of TD888: In a glass vial (20 mL), TD764·0.6TFA·1.0H₂O (56.5 mg; 84.3 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 4.0 mL; 2.00 mmol; 24 equiv.). and aq. TmCl₃ (100 mM; 1.00 mL; 100 μmol; 1.2 equiv.) and the mixture was stirred 6 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 68.0 mg (86%, 1 step; based on TD764·0.6TFA·1.0H₂O). ESI-HRMS: 750.1608 [M]⁺ (theor. [C₂₇H₃₂N₉O₄Cl₁Tm₁]⁺=750.1602). EA ([C₂₇H₃₂N₉O₄Cl₁Tm₁]⁺[TFA]⁻·0.2TFA·2.6H₂O, M_R=933.6): C 37.8 (37.7); H 4.0 (3.8); N 13.5 (13.4); Cl 3.8 (3.9); F 7.3 (7.3); Tm 18.1 (17.8).

Synthesis of TD899: Glass vial (4 mL) was charged with [TD888]⁺[TFA]⁻·0.2TFA·2.6H₂O (15.0 mg; 16.1 μmol; 1.0 equiv.), 2-(4-boronophenyl)acetic acid (4.2 mg; 23.3 μmol; 1.5 equiv.) and XPhos Pd G2 (0.7 mg; ˜0.9 μmol; 6 mol %) and was then three times secured with argon. Under constant flow of argon was then added dry 1,4-Dioxane (600 μL) through septum followed by addition of freshly prepared (and briefly washed with argon prior addition) aq. solution of K₃PO₄·H₂O (391 mM; 200 μL; 78 μmol; 4.9 equiv.). The mixture was then stirred 16 h under septum (but without external argon) at 80° C. Resulting heterogenous mixture was evaporated to dryness. Residue was re-dissolved in H₂O (3 mL), filtered through syringe microfilter (RC) and purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 10.1 mg (57%; 1 step; based on [TD888]⁺[TFA]⁻·0.2TFA·2.6H₂O). ESI-HRMS: 850.2362 [M]⁺ (theor. [C₃₅H₃₉N₉O₆Tm₁]⁺=850.2360). EA ([C₃₅H₃₉N₉O₆Tm₁]⁺[TFA]⁻·0.2TFA·7.0H₂O, M_R=1112.6): C 40.4 (40.6); H 4.8 (4.7); N 11.3 (11.1); F 6.1 (6.4).

Synthesis of TD822: In a glass vial (20 mL), TD810·0.5TFA·0.1FA·2.1H₂O (26 mg; 39 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. AcOH/NaOH buffer (500 mM; pH 5.8; 2.1 mL; 1.05 mmol; 27 equiv.) and aq. EuCl₃ (100 mM; 510 μL; 51 μmol; 1.3 equiv.) and the mixture was stirred 3 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 19 mg (≤59% assuming [M]⁺[TFA]⁻·xH₂O; M_R=836.6; 1 step; based on TD810·0.5TFA·0.1FA·2.1H₂O). ESI-HRMS: 724.1861 [M]⁺ (theor. [C₂₉H₃₃N₉O₄Eu₁]⁺=724.1862).

Synthesis of TD823: In a glass vial (20 mL), TD810·0.5TFA·0.1FA·2.1H₂O (28 mg; 42 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. AcOH/NaOH buffer (500 mM; pH 5.8; 2.3 mL; 1.15 mmol; 28 equiv.) and aq. TbCl₃ (100 mM; 530 μL; 53 μmol; 1.3 equiv.) and the mixture was stirred 2 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 22 mg (≤63% assuming [M]⁺[TFA]⁻·xH₂O; M_R=843.6; 1 step; based on TD810·0.5TFA·0.1FA·2.1H₂O). ESI-HRMS: 730.1899 [M]⁺ (theor. [C₂₉H₃₃N₉O₄Tb₁]⁺=730.1903).

Synthesis of TD831: In a glass vial (20 mL), TD827·0.8FA·1.6H₂O (50 mg; 63 μmol; 1.0 equiv.) was dissolved in a mixture of abs. EtOH (8 mL) and H₂O (7.5 mL) followed by addition aq. AcOH/NaOH buffer (500 mM; pH 5.8; 3.3 mL; 1.65 mmol; 26 equiv.) and aq. EuCl₃ (100 mM; 740 μL; 74 μmol; 1.2 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then diluted with EtOH (100 mL) and filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator. The residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 36 mg (≤58% assuming [M]⁺[TFA]⁻·xH₂O; M_R=993.0; 1 step; based on TD827·0.8FA·1.6H₂O). ESI-HRMS: 880.3189 [M]⁺ (theor. [C₃₈H₅₃N₉O₄Si₁Eu₁]⁺=880.3197).

Synthesis of TD885: In a glass vial (4 mL), [TD831]⁺[TFA]⁻·xH₂O (30.5 mg; 30.7 μmol; 1.0 equiv.) was dissolved in a H₂O (3.4 mL) followed by addition aq. K₂CO₃ (1.0 M; 155 μL; 155 μmol; ˜5 equiv.) and the mixture was stirred 40 min at 80° C. The resulting orange-brown (and not entirely homogenous) mixture was then filtered through syringe microfilter (RC) and the filtrate was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 15.4 mg (≤60% assuming [M]⁺[TFA]⁻·xH₂O; M_R=836.6; 1 step; based on [TD831]⁺[TFA]⁻·xH₂O). ESI-HRMS: 724.1858 [M]⁺ (theor. [C₂₉H₃₃N₉O₄Eu₁]⁺=724.1862).

Synthesis of TD832: In a glass vial (20 mL), TD827·0.8FA·1.6H₂O (47 mg; 59 μmol; 1.0 equiv.) was dissolved in a mixture of abs. EtOH (8 mL) and H₂O (8 mL) followed by addition aq. AcOH/NaOH buffer (500 mM; pH 5.8; 3.1 mL; 1.55 mmol; 26 equiv.) and aq. EuCl₃ (100 mM; 720 μL; 72 μmol; 1.2 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then diluted with EtOH (100 mL) and filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator. The residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 46 mg (≤78% assuming [M]⁺[TFA]⁻·xH₂O; M_R=999.9; 1 step; based on TD827·0.8FA·1.6H₂O). ESI-HRMS: 886.3229 [M]⁺ (theor. [C₃₈H₅₃N₉O₄Si₁Tb₁]⁺=886.3238).

Synthesis of TD886: In a glass vial (4 mL), [TD832]⁺[TFA]⁻·xH₂O (46.2 mg; 46.2 μmol; 1.0 equiv.) was dissolved in a H₂O (3.3 mL) followed by addition aq. K₂CO₃ (1.0 M; 230 μL; 230 μmol; ˜5 equiv.) and the mixture was stirred 40 min at 80° C. The resulting orange-brown (and not entirely homogenous) mixture was then filtered through syringe microfilter (RC) and the filtrate was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 29.3 mg (≤75% assuming [M]⁺[TFA]⁻·xH₂O; M_R=843.6; 1 step; based on [TD832]⁺[TFA]⁻·xH₂O). ESI-HRMS: 730.7901 [M]⁺ (theor. [C₂₉H₃₃N₉O₄Tb₁]⁺=730.1903).

Synthesis of TD829: In a glass vial (20 mL), TD827·0.8FA·1.6H₂O (31 mg; 39 μmol; 1.0 equiv.) was dissolved in a mixture of abs. EtOH (11 mL) and H₂O (6 mL) followed by addition aq. AcOH/NaOH buffer (500 mM; pH 5.8; 2.0 mL; 1.00 mmol; 26 equiv.) and aq. YbCl₃ (100 mM; 400 μL; 40 μmol; 1.0 equiv.) and the mixture was stirred 8 h at 80° C. Mixture was then diluted with MeOH (20 mL) and filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator. The residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 38 mg (≤96% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1014.0; 1 step; based on TD827·0.8FA·1.6H₂O). ESI-HRMS: 901.3372 [M]⁺ (theor. [C₃₈H₅₃N₉O₄Si₁Yb₁]⁺=901.3373).

Synthesis of TD834: In a glass vial (4 mL), [TD829]⁺[TFA]⁻·xH₂O (37.9 mg; 37.4 μmol; 1.0 equiv.) was dissolved in a 50% aq. MeOH (18 mL) followed by addition aq. K₂CO₃ (100 mM; 2.0 mL μL; 200 μmol; ˜5 equiv.) and the mixture was stirred 1 h at 80° C. The resulting mixture was then concentrated to ˜3 mL and then purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 22.5 mg (≤65% assuming [M]⁺[TFA]⁻·xH₂O; M_R=921.8; 1 step; based on [TD829]⁺[TFA]⁻·xH₂O). ESI-HRMS: 809.2570 [M]⁺ (theor. [C₃₁H₄₁N₉O₆Yb₁]⁺=809.2563).

Synthesis of TD833: In a glass vial (20 mL), TD827·0.8FA·1.6H₂O (64.8 mg; 81 μmol; 1.0 equiv.) was dissolved in a mixture of i-PrOH (10 mL) and H₂O (5 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 4.1 mL; 2.05 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 900 μL; 90 μmol; 1.1 equiv.) and the mixture was stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator. The residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 76.3 mg (78%; 1 step; based on TD827·0.8FA·1.6H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.06-1.32 (i-Pr, m, 21H); 2.63-3.81 (mc, CH₂—CO, m, 16+4H); 3.90 (CH₂-arom., d, 1H, ²J_HH=15); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.28 (CH₂-arom., d, 1H, ²J_HH=15); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.55 (CH₂—N₃, d, 1H, ²J_HH=16); 7.09 (CH₂—N₃, d, 1H, ²J_HH=16); 7.76 (arom., d, 1H, J_HH=1); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH—N₃, s, 1H); 8.06 (arom., d, 1H, 4J_HH=1); 8.24 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 902.3386 [M]⁺ (theor. [C₃₈H₅₃N₉O₄Si₁Lu₁]⁺=902.3392). EA ([C₃₈H₅₃N₉O₄Si₁Lu₁]⁺[TFA]⁻·1.0TFA·4.0H₂O, M_R=1202.0): C 42.0 (41.7); H 5.2 (5.0); N 10.5 (10.4); Si 2.3 (1.9); F 9.5 (9.4).

Synthesis of MIS007: In a glass vial (40 mL), [TD833]⁺[TFA]⁻·1.0TFA·4.0H₂O (19 mg; 16 μmol; 1.0 equiv.) was dissolved in a 50% aq. MeCN (20 mL) followed by addition aq. K₂CO₃ (100 mM; 2.0 mL; 200 μmol; ˜10 equiv.) and the mixture was stirred 1 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated to ˜3 mL and then purified by preparative HPLC (C₁₈; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 13 mg (≤81% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1016.0; 1 step; based on [TD833]⁺[TFA]⁻·1.0TFA·4.0H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 2.68-3.84 (mc, CH₂—CO, m, 16+4H); 3.96 (CH₂-arom., d, 1H, ²J_HH==15); 4.17 (CH₂-arom., d, 1H, ²J_HH=16); 4.18 (C≡CH, s, 1H); 4.30 (CH₂-arom., d, 1H, ²J_HH=15); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 5.61 (CH₂—N₃, d, 1H, ²J_HH=16); 7.11 (CH₂—N₃, d, 1H, ²J_HH=16); 7.82 (arom., d, 1H, 4J_HH=2); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 8.11 (arom., d, 1H, 4J_HH=2); 8.27 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 746.2059 [M]⁺ (theor. [C₂₉H₃₃N₉O₄Lu₁]⁺=746.2058).

Synthesis of TD1113: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (4.0 mg; 6.2 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 310 μL; 155 μmol; 25 equiv.) and aq. PrCl₃ (100 mM; 67 μL; 6.7 μmol; 1.1 equiv.) and the mixture was stirred 10 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 0.6 mg (≤10% assuming [M]⁺[TFA]⁻·1.0TFA·xH₂O; M_R=985.9; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜3): ¹⁹F δ_F −66.45 (bs). NMR (˜0.5 mM TD1113 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.49 (bs; ΔH_1/2=135.2 Hz). ESI-HRMS: 756.1593 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Pr₁]⁺=756.1600).

Synthesis of TD1114: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (4.0 mg; 6.2 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 310 μL; 155 μmol; 25 equiv.) and aq. NdCl₃ (100 mM; 67 μL; 6.7 μmol; 1.1 equiv.) and the mixture was stirred 10 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 2.0 mg (≤33% assuming [M]⁺[TFA]⁻·0.9TFA·xH₂O; M_R=975.5; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜3): ¹⁹F δ_F −66.75 (s). NMR (˜0.5 mM TD1114 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.76 (s; ΔH_1/2=47.4 Hz). ESI-HRMS: 757.1595 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Nd₁]⁺=757.1601).

Synthesis of TD1115: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (4.0 aq. MOPS/NaOH buffer (500 mM; pH 7.0; 310 μL; 155 μmol; 25 equiv.) and aq. SmCl₃ (100 mM; 67 μL; 6.7 μmol; 1.1 equiv.) and the mixture was stirred 10 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 3.6 mg (≤63% assuming [M]⁺[TFA]⁻·0.3TFA·xH₂O; M_R=913.2; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −66.03 (s). NMR (˜0.5 mM TD1115 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.06 (s; ΔH_1/2=1.9 Hz). ESI-HRMS: 767.1713 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Sm₁]⁺=767.1721).

Synthesis of TD1072: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. EuCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 8 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 2.7 mg (≤66% assuming [M]⁺[TFA]⁻·0.3TFA·xH₂O; M_R=914.8; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −62.77 (s). NMR (˜0.5 mM TD1072 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −62.79 (s; ΔH_1/2=3.3 Hz). ESI-HRMS: 768.1738 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Eu₁]⁺=768.1736).

Synthesis of TD1179: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (4.0 mg; 6.5 μmol; 1.0 equiv.) was dissolved in H₂O (13 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 326 μL; 163 μmol; 25 equiv.) and aq. GdCl₃ (100 mM; 78 μL; 7.8 μmol; 1.2 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 2.2 mg (≤36% assuming [M]⁺[TFA]⁻·0.9TFA·xH₂O; M_R=988.5; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −62.98 (bs). NMR (˜0.5 mM TD1179 in −50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −62.97 (bs; ΔH_1/2=342.9 Hz). ESI-HRMS: 773.1779 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Gd₁]⁺=773.1765).

Synthesis of TD1073: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. TbCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 6 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 2.8 mg (≤64% assuming [M]⁺[TFA]⁻·0.7TFA·xH₂O; M_R=967.3; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −107.22 (bs). NMR (˜0.5 mM TD1073 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −107.50 (bs; ΔH_1-2=708.6 Hz). ESI-HRMS: 774.1779 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Tb₁]⁺=774.1777).

Synthesis of TD1074: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. DyCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 5 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 3.3 mg (≤75% assuming [M]⁺[TFA]⁻·0.7TFA·xH₂O; M_R=970.9; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −142.86 (s). NMR (˜0.5 mM TD1074 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −143.22 (s; ΔH_1/2=47.2 Hz). ESI-HRMS: 779.1816 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Dy₁]⁺=779.1816).

Synthesis of TD1075: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. HoCl₃(100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 5 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 4.0 mg (≤90% assuming [M]⁺[TFA]⁻·0.8TFA·xH₂O; M_R=984.7; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −85.69 (bs). NMR (˜0.5 mM TD1075 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −85.79 (bs; ΔH_1/2=185.8 Hz). ESI-HRMS: 780.1829 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Ho₁]⁺=780.1827).

Synthesis of TD1076: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. ErCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 4.1 mg (≤92% assuming [M]⁺[TFA]⁻·1.0TFA·xH₂O; M_R=987.1; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −47.48 (s). NMR (˜0.5 mM TD1076 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −47.42 (s; ΔH_1/2=19.3 Hz). ESI-HRMS: 781.1824 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Er₁]⁺=781.1827).

Synthesis of 1077: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. TmCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 4.2 mg (≤92% assuming [M]⁺[TFA]⁻·1.0TFA·xH₂O; M_R=1011.6; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −57.57 (bs). NMR (˜0.5 mM TD1077 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −57.51 (bs; ΔH_1-2=138.72 Hz). ESI-HRMS: 784.1863 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Tm₁]⁺=784.1866).

Synthesis of 1078: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. YbCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 3.7 mg (≤82% assuming [M]⁺[TFA]⁻·0.9TFA·xH₂O; M_R=1004.3; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹⁹F δ_F −59.01 (s). NMR (˜0.5 mM TD1078 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −59.00 (s; ΔH_1/2=18.4 Hz). ESI-HRMS: 789.1913 [M]⁺ (theor. [C₂₈H₃N₉O₄F₃Yb₁]=789.1912).

Synthesis of TD1079: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (14.7 mg; 22.8 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1150 μL; 575 μmol; 25 equiv.) and aq. LuCl₃ (100 mM; 250 μL; 25.0 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 16.1 mg (70%; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.69-3.85 (mc, CH₂—CO, m, 16+4H); 4.12 (CH₂-arom., d, 1H, ²J_HH=15); 4.19 (CH₂-arom., d, 1H, ²J_HH=16); 4.38 (CH₂-arom., d, 1H, ²J_HH=15); 4.88 (CH₂-arom., d, 1H, ²J_HH=16); 5.75 (CH₂—N₃, d, 1H, ²J_HH=15); 7.23 (CH₂—N₃, d, 1H, ²J_HH=15); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 8.12 (arom., d, 1H, ⁴J_HH=2); 8.28 (arom., t, 1H, ³J_HH=8), 8.43 (arom., d, 1H, ⁴J_HH=2). ¹⁹F δ_F −66.10 (s). NMR (˜0.5 mM TD1079 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.13 (s; ΔH_1/2=2.4 Hz). ESI-HRMS: 790.1931 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Lu₁]⁺=790.1932). EA ([C₂₈H₃₂N₉O₄Lu₁F₃]⁺[TFA]⁻·0.2TFA·4.1H₂O, M_R=1000.2): C 36.5 (36.2); H 4.1 (3.6); N 12.6 (12.3); F 12.5

Synthesis of TD1080: In a glass vial (20 mL), TD1063·0.1FA·1.2H₂O (2.9 mg; 4.6 μmol; 1.0 equiv.) was dissolved in H₂O (10 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 225 μL; 113 μmol; 25 equiv.) and aq. YCl₃ (100 mM; 55 μL; 5.5 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 3.6 mg (≤94% 0 assuming [M]⁺[TFA]⁻·0.3TFA·xH₂O; M_R=851.7; 1 step; based on TD1063·0.1FA·1.2H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.66-3.87 (mc, CH₂—CO, m, 16+4H); 4.11 (CH₂-arom., d, 1H, ²J_HH=15); 4.18 (CH₂-arom., d, 1H, ²J_HH=16); 4.42 (CH₂-arom., d, 1H, ²J_HH=15); 4.89 (CH₂-arom., d, 1H, ²J_HH=16); 5.80 (CH₂—N₃, d, 1H, ²J_HH=16); 7.16 (CH₂—N₃, d, 1H, ²J_HH=16); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 8.13 (arom., d, 1H, ⁴J_HH=2); 8.28 (arom., t, 1H, ³J_HH=8), 8.43 (arom., d, 1H, ⁴J_HH=2). ¹⁹F δ_F −66.10 (s). NMR (˜0.5 mM TD1080 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.12 (s; ΔH_1/2=2.1 Hz). ESI-HRMS: 704.1583 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Y,]⁺=704.1582).

Synthesis of TD651: In a glass vial (20 mL), TD647·0.2FA·0.9H₂O (30 mg; 46 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.30 mL; 1.15 mmol; 25 equiv.) and aq. LaCl₃ (100 mM; 500 μL; 50 μmol; 1.1 equiv.) and the mixture was stirred 14 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 15 mg (36%; 1 step; based on TD647·0.2FA·9H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 2.54-3.63 (mc, CH₂—CO, m, 16+3H); 3.96 (CH₂-arom., d, 1H, ²J_HH=15); 4.00 (CH₂-arom., d, 1H, ²J_HH=14); 4.09 (CH₂—CO, 1H, d, ²J_HH=17); 4.23 (CH₂-arom., d, 1H, ²J_HH=15); 4.25 (CH₂-arom., d, 1H, ²J_HH=14); 5.72 (CH₂—N₃, d, 1H, ²J_HH=16); 6.62 (CH₂—N₃, d, 1H, ²J_HH=16); 7.58-7.66 (Ph, m, 3H); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83-7.95 (Ph, arom., m, 2+1H); 8.06 (arom., d, 1H, ⁴J_HH=2); 8.16 (CH N₃, s, 1H); 8.22 (arom., t, 1H, ³J_HH=8); 8.42 (FA, s, 1H). ¹³C{¹H} δ_C 53.5 (CH₂—N₃, s); 56.3 (mc, s); 58.7 (mc, s); 58.9 (mc, s); 59.2 (mc, s); 59.3 (mc, s); 60.0 (mc, s); 61.9 (mc, s); 62.5 (CH₂—CO, s); 63.5 (mc, s); 65.1 (CH₂—CO, s); 65.2 (CH₂-arom., s); 66.6 (CH₂-arom., s); 124.1 (arom., s); 124.6 (arom., s); 127.1 (arom., s); 127.9 (arom., s); 128.1 (Ph, s); 130.2 (Ph, s); 131.5 (Ph, s); 136.1 (arom, s); 136.2 (Ph., s); 136.8 (CH—N₃, s); 142.0 (arom., s); 144.9 (arom., s); 153.6 (arom., s); 157.0 (arom., s); 157.5 (arom., s); 159.0 (arom., s); 171.0 (FA, s); 179.0 (CO, s); 180.4 (CO, s). ESI-HRMS: 762.2024 [M]⁺ (theor. [C₃₃H₃₇N₉O₄La₁]⁺=762.2027). EA ([C₃₃H₃₇N₉O₄La₁]⁺[FA]⁻·4.8H₂O, M_R=894.1): C 45.7 (46.1); H 5.4 (4.7); N 14.1 (13.6); La 15.5 (15.0).

Synthesis of TD870: In a glass vial (20 mL), TD647·1.3TFA (30.5 mg; 39.4 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.30 mL; 1.15 mmol; 29 equiv.) and aq. CeCl₃ (100 mM; 545 μL; 54.5 μmol; 1.4 equiv.) and the mixture was stirred 14 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 21.2 mg (58%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 763.2012 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Ce₁]⁺=763.2017). EA ([C₃₃H₃₇N₉O₄Ce₁]⁺[FA]⁻·6.5H₂O, M_R=925.9): C 44.1 (44.7); H 5.6 (5.1); N 13.6 (13.1); Ce 15.1 (14.5).

Synthesis of TD869: In a glass vial (20 mL), TD647·1.3TFA (26.4 mg; 34.1 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.40 mL; 1.20 mmol; 35 equiv.) and aq. PrCl₃ (100 mM; 500 μL; 50.0 μmol; 1.5 equiv.) and the mixture was stirred 14 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 17.7 mg (56%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 764.2035 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Pr₁]⁺=764.2040). EA ([C₃₃H₃₇N₉O₄Pr₁]⁺[FA]⁻·6.4H₂O, M_R=924.9): C 44.2 (44.7); H 5.5 (5.0); N 13.6 (13.1); Pr 15.2 (14.8).

Synthesis of TD868: In a glass vial (20 mL), TD647·1.3TFA (25.7 mg; 33.2 mol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.30 mL; 1.15 mmol; 35 equiv.) and aq. NdCl₃ (100 mM; 460 μL; 46.0 μmol; 1.4 equiv.) and the mixture was stirred 12 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 19.8 mg (65%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 765.2039 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Nd₁]⁺=765.2040). EA ([C₃₃H₃₇N₉O₄Nd₁]⁺[FA]⁻·5.6H₂O, M_R=913.9): C 44.7 (45.0); H 5.4 (4.6); N 13.8 (13.4); Nd 15.8 (15.2).

Synthesis of TD867: In a glass vial (20 mL), TD647·1.3TFA (25.6 mg; 33.1 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.30 mL; 1.15 mmol; 35 equiv.) and aq. SmCl₃ (100 mM; 460 μL; 46.0 μmol; 1.4 equiv.) and the mixture was stirred 12 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 22.3 mg (73%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 775.2158 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Sm₁]⁺=775.2160). EA ([C₃₃H₃₇N₉O₄Sm₁]⁺[FA]⁻·5.8H₂O, M_R=923.6): C 44.2 (44.7); H 5.4 (4.9); N 13.6 (13.3); Nd 16.3 (15.8).

Synthesis of TD599: In a glass vial (20 mL), TD647·1.3H₂O (50 mg; 77 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.75 mL; 1.88 mmol; 24 equiv.) and aq. EuCl₃ (100 mM; 825 μL; 83 μmol; 1.1 equiv.) and the mixture was stirred 3 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 44 mg (63%; 1 step; based on TD647·1.3H₂O). ESI-HRMS: 776.2171 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Eu₁]⁺=776.2175). EA ([C₃₃H₃₇N₉O₄Eu₁]⁺[FA]⁻·4.6H₂O, M_R=903.6): C 45.2 (45.3); H 5.3 (5.1); N 14.0 (13.7); Eu 16.8 (16.5).

Synthesis of TD451: In a glass vial (2 mL), TD647·2.2H₂O (2.0 mg; 3.1 μmol; 1.0 equiv.) was dissolved in aq. MOPS/NaOH buffer (500 mM; pH 7.0; 155 μL; 77.5 μmol; 25 equiv.) and aq. GdCl₃ (100 mM; 34 μL; 120 μmol; 1.1 equiv.) and the mixture was stirred 2 d at RT. Mixture was then diluted with H₂O and filtered through syringe microfilter (RC). The filtrate was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 0.3 mg.

Synthesis of TD527: In a glass vial (40 mL), TD647·2.2H₂O (75 mg; 113 μmol; 1.0 equiv.) was dissolved in H₂O (32 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 4.60 mL; 2.30 mmol; 20 equiv.) and aq. GdCl₃ (100 mM; 1.20 mL; 120 μmol; 1.1 equiv.) and the mixture was stirred 2 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 58 mg (56%; 1 step; based on TD647·2.2H₂O). ESI-HRMS: 781.2218 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Gd₁]⁺=781.2204). EA ([C₃₃H₃₇N₉O₄Gd₁]⁺[FA]⁻·5.3H₂O, M_R=921.5): C 44.3 (44.7); H 5.3 (4.7); N 13.7 (13.4); Gd 17.1 (16.2).

Synthesis of TD600: In a glass vial (20 mL), TD647·1.3H₂O (50 mg; 77 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.75 mL; 1.88 mmol; 24 equiv.) and aq. TbCl₃ (100 mM; 825 μL; 83 μmol; 1.1 equiv.) and the mixture was stirred 3 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 49 mg (69%; 1 step; based on TD647·1.3H₂O). ESI-HRMS: 782.2211 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Tb₁]⁺=781.2217). EA ([C₃₃H₃₇N₉O₄Tb₁]⁺[FA]⁻·4.9H₂O, M_R=915.9): C 44.6 (44.7); H 5.3 (5.1); N 13.8 (13.6); Tb 17.4 (17.1).

Synthesis of TD866: In a glass vial (20 mL), TD647·1.3TFA (20.0 mg; 25.8 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.84 mL; 920 μmol; 36 equiv.) and aq. DyCl₃ (100 mM; 370 μL; 37.0 μmol; 1.4 equiv.) and the mixture was stirred 46 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 22.2 mg (89%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 787.2248 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Dy₁]⁺=787.2255). EA ([C₃₃H₃₇N₉O₄Dy₁]⁺[FA]⁻·7.7H₂O, M_R=970.0): C 42.1 (42.5); H 5.5 (5.0); N 13.0 (12.6); Dy 16.8 (16.1).

Synthesis of TD648: In a glass vial (20 mL), TD647·0.2FA·0.9H₂O (22 mg; 34 mol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.72 mL; 860 μmol; 25 equiv.) and aq. HoCl₃ (100 mM; 375 μL; 38 μmol; 1.1 equiv.) and the mixture was stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 24 mg (76%; 1 step; based on TD647·0.2FA·9H₂O). ESI-HRMS: 788.2265 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Ho₁]⁺=788.2266). EA ([C₃₃H₃₇N₉O₄Ho₁]⁺[FA]⁻·5.0H₂O, M_R=923.7): C 44.2 (44.2); H 5.2 (4.8); N 13.6 (13.3); Ho 17.9 (17.3).

Synthesis of TD865: In a glass vial (20 mL), TD647·1.3TFA (20.5 mg; 26.5 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.84 mL; 920 μmol; 35 equiv.) and aq. ErCl₃ (100 mM; 370 μL; 37.0 μmol; 1.4 equiv.) and the mixture was stirred 22 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 22.8 mg (90%; 1 step; based on TD647·1.3TFA). ESI-HRMS: 791.2280 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Er₁]⁺=791.2302). EA ([C₃₃H₃₇N₉O₄Er₁]⁺[FA]⁻·6.9H₂O, M_R=960.3): C 42.5 (42.4); H 5.4 (4.9); N 13.1 (12.7); Er 17.4 (16.8).

Synthesis of TD601: In a glass vial (20 mL), TD647·1.3H₂O (49 mg; 75 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.75 mL; 1.88 mmol; 25 equiv.) and aq. TmCl₃ (100 mM; 825 μL; 83 μmol; 1.1 equiv.) and the mixture was stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 51 mg (73%; 1 step; based on TD647·1.3H₂O). ESI-HRMS: 792.2299 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Tm₁]⁺=792.2305). EA ([C₃₃H₃₇N₉O₄Tm₁]⁺[FA]⁻·4.7H₂O, M_R=922.3): C 44.3 (44.4); H 5.2 (5.1); N 13.7 (13.5); Tm 18.3 (18.3).

Synthesis of TD602: In a glass vial (20 mL), TD647·1.3H₂O (49 mg; 75 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.75 mL; 1.88 mmol; 25 equiv.) and aq. YbCl₃ (100 mM; 825 μL; 83 μmol; 1.1 equiv.) and the mixture was stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 53 mg (77%; 1 step; based on TD647·1.3H₂O). ESI-HRMS: 797.2347 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Yb₁]⁺=797.2352). EA ([C₃₃H₃₇N₉O₄Yb₁]⁺[FA]⁻·4.2H₂O, M_R=917.4): C 44.5 (44.1); H 5.1 (5.1); N 13.7 (13.3); Yb 18.4 (18.7).

Synthesis of TD522: In a glass vial (20 mL), TD647·1.3TFA (30.0 mg; 38.8 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.30 mL; 1.15 mmol; 30 equiv.) and aq. LuCl₃ (100 mM; 500 μL; 50.0 μmol; 1.3 equiv.) and the mixture was stirred 4 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 32.6 mg (89%; 1 step; based on TD647·1.3TFA). NMR (D₂O, pD ˜5): ¹H δ_H 2.62-3.83 (mc, CH₂—CO, m, 16+4H); 3.99 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.32 (CH₂-arom., d, 1H, ²J_HH=15); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.66 (CH₂—N₃, d, 1H, ²J_HH=15); 7.13 (CH₂—N₃, d, 1H, ²J_HH=15); 7.60-7.67 (Ph, m, 3H); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH N₃, s, 1H); 7.91-7.97 (Ph, m, 2H); 7.99 (arom., d, 1H, ⁴J_HH=2); 8.25 (arom., t, 1H, ³J_HH=8); 8.31 (arom., d, 1H, ⁴J_HH=2); 8.38 (FA, s, 1H). ¹³C{¹H} δ_C 48.9 (mc, bs); 49.1 (mc, bs); 51.8 (mc, bs); 51.9 (mc, bs); 52.9 (CH₂—N₃, s); 53.8 (mc, s); 53.9 (mc, bs); 54.9 (mc, s); 56.0 (mc, s); 59.2 (CH₂—CO, s); 59.6 (CH₂-arom., s); 59.7 (CH₂-arom., s); 61.0 (CH₂—CO, s); 123.7 (arom., s); 126.5 (arom., s); 127.7 (arom., s); 128.3 (Ph, s); 130.3 (Ph, s); 130.5 (arom., s); 131.8 (Ph, s); 136.0 (Ph, s); 136.4 (CH—N₃, s); 138.4 (arom., s); 142.6 (arom., s); 146.4 (arom., s); 154.7 (arom., s); 156.0 (arom., s); 158.7 (arom., s); 158.8 (arom., s); 170.0 (FA, s); 177.9 (CO, s); 179.4 (CO, s). ESI-HRMS: 798.2377 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Lu₁]⁺=798.2371). EA ([C₃₃H₃₇N₉O₄Lu₁]⁺[FA]⁻·5.5H₂O, M_R=942.8): C 43.3 (43.7); H 5.2 (4.6); N 13.4 (13.1); Lu 18.6 (18.0).

Synthesis of TD776: In a glass vial (4 mL), [TD522]⁺[FA]⁻·5.5H₂O (9.0 mg; 9.5 μmol; 1.0 equiv.) was dissolved in D₂O (500 μL) and evaporated to dryness. Residue was re-dissolved in D₂O (500 μL) followed by addition of neat DBU (29 μL; 194 μmol; 20 equiv.) and the resulting solution was stirred 2 d at 80° C. Mixture was then evaporated to dryness. Residue was re-dissolved in D₂O (500 μL) followed by addition of another portion of neat DBU (15 μL; 100 μmol; ˜10 equiv.) and the resulting solution was further stirred 16 h at 80° C. Mixture was then quenched by addition of FA (75 μL; 2.92 mmol; ˜300 equiv.) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give crude product in the form of formate salt as white fluffy solid (¹H NMR analysis found ˜1 equiv. of DBU or its byproducts apart from otherwise pure deka-deuterated chelate). Bulk of the material was therefore re-purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 7.6 mg (≤87% assuming [M]⁺[TFA]⁻·xH₂O; M_R=921.7; 1 step; based on [TD522]⁺[FA]⁻·5.5H₂O). NMR (D₂O, pD ˜4): ¹H δ_H 2.64-3.83 (mc, m, 16H); 7.59-7.67 (Ph, m, 3H); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (CH—N₃, s, 1H); 7.90-7.96 (Ph, m, 2H); 7.98 (arom., d, 1H, ⁴J_HH=2); 8.24 (arom., t, 1H, ³J_HH=8); 8.30 (arom., d, 1H, ⁴J_HH=2); 8.39 (FA, s, 1H). ¹³C{¹H} δ_C 48.9 (mc, bs); 49.2 (mc, bs); 51.8 (mc, bs); 51.9 (mc, bs); 52.0-52.9 (CD₂-N₃, bm); 53.8 (mc, s); 53.9 (mc, bs); 54.8 (mc, s); 55.9 (mc, s); 58.2-59.7 (CD₂-CO, 2×CD₂-arom., bm); 59.7-60.9 (CD₂-CO, s); 123.8 (arom., s); 126.5 (arom., s); 127.8 (arom., s); 128.3 (Ph, s); 130.3 (Ph, s); 130.5 (arom., s); 131.8 (Ph, s); 136.1 (Ph, s); 136.4 (CH—N₃, s); 138.5 (arom., s); 142.6 (arom., s); 146.4 (arom., s); 154.8 (arom., s); 156.0 (arom., s); 158.7 (arom., s); 158.8 (arom., s); 170.5 (FA, s); 178.0 (CO, s); 179.4 (CO, s). ESI-HRMS: 808.3004 [M]⁺ (theor. [C₃₃H₂₇D₁₀N₉O₄Lu₁]⁺=808.2998).

Synthesis of TD688: In a glass vial (2 mL), [TD522]⁺[FA]⁻·5.5H₂O (1 mg; ˜1 μmol; 1.0 equiv.) was dissolved in MeOH (1 mL) followed by addition of solid NaBH₄ (4 mg; −100 mmol; ˜100 equiv.). The resulting open vial was stirred 1 h at RT after which further portions of NaBH₄ were added until all starting material was consumed (analyzed by LC-MS). The mixture was then diluted with H₂O (2 mL), neutralized with neat FA (200 μL) and filtered through syringe microfilter (RC). Filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: <1 mg. NMR (D₂O, pD ˜6): ¹H δ_H 1.42-2.23 (Pip., m, 6H); 2.52-3.70 (mc, CH₂—CO, CH₂—Pip., m, 16+3+2H); 3.76 (Pip., m, 1H); 4.16 (CH₂—CO, d, ²J_HH=17); 4.22 (CH₂-arom., d, 1H, ²J_HH=16); 4.32 (CH₂-arom., d, 1H, ²J_HH=16); 4.78 (Pip., m, 1H); 5.66 (CH₂—N₃, d, 1H, ²J_HH=16); 6.88 (CH₂—N₃, d, 1H, ²J_HH=16); 7.68-7.74 (Ph, m, 3H); 7.91 (CH—N₃, s, 1H); 7.98 (arom., d, 1H, ⁴J_HH=2); 7.98-8.02 (Ph, m, 2H); 8.25 (arom., d, 1H, ⁴J_HH=2); 8.52 (FA, s). ¹³C{¹H} δ_C 22.8 (Pip., s); 27.0 (Pip., s); 29.5 (Pip., s); 50.1 (Pip., s); 51.4 (CH₂—N₃, s); 52.1 (mc, s); 53.4 (mc, s); 54.4 (mc, s); 54.5 (Pip., s); 55.4 (mc, s); 55.6 (mc, s); 56.0 (mc, s); 56.1 (mc, s); 56.8 (mc, s); 56.0 (CH₂-Pip., s); 64.7 (CH₂—CO, s); 64.8 (CH₂-arom., s); 65.4 (CH₂-Pip., s); 119.8 (arom., s); 123.7 (arom., s); 126.9 (Ph, s); 129.0 (Ph, s); 130.5 (Ph, s); 131.6 (CH—N₃, s); 135.7 (Ph, s); 138.9 (arom., s); 153.1 (arom., s); 155.9 (arom., s); 159.0 (arom., s); 170.5 (FA, s); 178.8 (CO, s); 179.5 (CO, s). ESI-HRMS: 804.2841 [M]⁺ (theor. [C₃₃H₄₃N₉O₄Lu₁]⁺=804.2840).

Synthesis of TD739: In a glass vial (2 mL), [TD522]⁺[FA]⁻·5.5H₂O (10 mg; 11 μmol; 1.0 equiv.) was dissolved in CD₃OD (1 mL) followed by addition of solid NaBD₄ (44 mg; 1.05 mmol; ˜100 equiv.). The resulting open vial was stirred 1 h at RT after which another portion of NaBD₄ (28 mg; 0.67 mmol; ˜60 equiv.) was added. Mixture was further stirred with 1 h at RT. The mixture was then diluted with H₂O (2 mL), neutralized with neat FA (160 μL; ˜400 equiv.) and filtered through syringe microfilter (RC). Filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product (major diastereoisomer) were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 6 mg (˜60%; 1 step; based on [TD522]⁺[FA]⁻·5.5H₂O). NMR (D₂O, pD ˜5): 1.33-1.77 (Pip., m, 1H); 1.93-2.09 (Pip., m, 2H); 2.42-3.62 (mc, CH₂—CO, CH₂—Pip. m, 16+3H+1H); 4.07 (CH₂—CO, d, 1H, ²J_HH=17); 4.19 (CHD-arom., s, 1H); 5.56 (CH₂—N₃, d, 1H, ²J_HH=16); 6.78 (CH₂—N₃, d, 1H, ²J_HH=16); 7.59-7.65 (Ph, m, 3H); 7.82 (CH N₃, s, 1H); 7.87 (arom., d, 1H, ⁴J_HH=2); 7.88-7.93 (Ph, m, 2H); 8.14 (arom., d, 1H, ⁴J_HH=2); 8.43 (FA, s, 1H). ¹³C{¹H} δ_C 23.4 (Pip., bs); 27.7 (Pip., bs); 30.3 (Pip., bs); 50.9 (Pip., bs); 52.7 (CH₂—N₃, s); 53.4 (mc, s); 54.7 (mc, s); 55.3 (Pip., bs); 55.7 (mc, s); 56.7 (mc, s); 56.8 (mc, s); 57.3 (mc, s); 57.4 (mc, s); 58.1 (mc, s); 61.2 (CH₂—CO, s); 65.8 (CHD-arom., bs); 66.0 (CH₂-Pip., s); 66.8 (CH₂—CO, s); 121.1 (arom., s); 125.0 (arom., s); 128.2 (Ph, s); 130.3 (Ph, s); 131.8 (Ph, s); 132.9 (arom., s); 135.9 (Ph, s); 140.2 (arom., s); 154.3 (arom., s); 157.2 (arom., s); 160.3 (arom., s); 171.4 (FA, s); 180.1 (CO, s); 180.8 (CO, s). ESI-HRMS: 810.3215 [M]⁺ (theor. [C₃₃H₃₇D₆N₉O₄Lu₁]⁺=810.3217).

Synthesis of TD649: In a glass vial (20 mL), TD647·0.2FA·0.9H₂O (38 mg; 59 μmol; 1.0 equiv.) was dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.96 mL; 1.48 mmol; 25 equiv.) and aq. YCl₃ (100 mM; 650 μL; 65 μmol; 1.1 equiv.) and the mixture was stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 32 mg (65%; 1 step; based on TD647·0.2FA·9H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 2.58-3.86 (mc, CH₂—CO, m, 16+4H); 3.99 (CH₂-arom., d, 1H, ²J_HH=15); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.37 (CH₂-arom., d, 1H, ²J_HH=15); 4.85 (CH₂-arom., d, 1H, ²J_HH=16); 5.71 (CH₂—N₃, d, 1H, ²J_HH=16); 7.07 (CH₂—N₃, d, 1H, ²J_HH=16); 7.58-7.68 (Ph, m, 3H); 7.78-7.86 (arom., m, 2H); 7.89 (CH N₃, s, 1H); 7.91-7.97 (Ph, m, 2H); 7.99 (arom., d, 1H, ⁴J_HH=2); 8.26 (arom., t, 1H, ³J_HH=8); 8.31 (arom., d, 1H, ⁴J_HH=2); 8.42 (FA, s, 1H). ¹³C{¹H} δ_C 49.0 (mc, s); 49.2 (mc, s); 51.4 (mc, s); 51.7 (mc, s); 53.0 (CH₂—N₃, s); 53.9 (mc, s); 54.1 (mc, s); 54.7 (mc, s); 55.7 (mc, s); 59.5 (CH₂—CO, s); 59.6 (CH₂-arom., s); 59.8 (CH₂-arom., s); 61.4 (CH₂—CO, s); 123.9 (arom., s); 126.5 (arom., s); 127.6 (arom., s); 128.4 (Ph, s); 130.1 (arom., s); 130.3 (Ph, s); 131.8 (Ph, s); 136.2 (Ph, s); 136.8 (CH—N₃, s); 138.2 (arom., s); 142.8 (arom., s); 146.0 (arom., s); 155.0 (arom., s); 155.6 (arom., s); 158.6 (arom., s); 158.7 (arom., s); 171.2 (FA, s); 177.7 (CO, s); 179.0 (CO, s). ESI-HRMS: 712.2017 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Y₁]⁺=712.2022). EA ([C₃₃H₃₇N₉O₄Y₁]⁺[FA]⁻·4.5H₂O, M_R=838.7): C 48.7 (48.6); H 5.6 (5.2); N 15.0 (14.7); Y 10.6 (10.3).

Synthesis of TD890: In a glass vial (4 mL), TD650·1.1FA·1.6H₂O (15.2 mg; 21.6 μmol; 1.0 equiv.) was dissolved in H₂O (2 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.10 mL; 550 μmol; 25 equiv.) and aq. Zn(NO₃)₂ (51.7 mM; 460 μL; 23.8 μmol; 1.1 equiv.) and the mixture was stirred 2 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with no additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 15.5 mg (91%; 1 step; based on TD650·1.1FA·1.6H₂O). NMR (D₂O, pD ˜8): ¹H δ_H 2.43-3.38 (mc, CH₂—CO, bm, 16+4H); 4.14 (CH₂-arom., s, 2H); 4.25 (CH₂-arom., bs, 2H); 6.48 (CH₂—N₃, bs, 2H); 7.60 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.62-7.68 (Ph, m, 3H); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., d, 1H, ⁴J_HH=2); 7.91-7.98 (Ph, m, 2H); 8.09 (arom., t, 1H, ³J_HH=8); 8.21 (CH—N₃, s, 1H); 8.31 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 688.2339 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Zn₁]⁺=688.2333). EA ([C₃₃H₃₇N₉O₄Zn₁]·5.5H₂O, M_R=788.2): C 50.3 (50.2); H 6.1 (5.8); N 16.0 (15.7); Zn 8.3 (8.5).

Synthesis of TD1195: In a glass vial (4 mL), TD650·1.1FA·1.6H₂O (9.0 mg; 12.8 μmol; 1.0 equiv.) was dissolved in H₂O (780 μL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 650 μL; 325 μmol; 25 equiv.) and aq. MnCl₂ (25.0 mM; 570 μL; 14.3 μmol; 1.1 equiv.) and the mixture was stirred 1 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 7.5 mg (74%; 1 step; based on TD650·1.1FA·1.6H₂O). ESI-HRMS: 679.2423 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Mn₁]⁺=679.2422). EA ([C₃₃H₃₇N₉O₄Mn₁]·6.4H₂O, M_R794.0): C 49.9 (49.5); H 6.3 (5.9); N 15.9 (15.7); Mn 6.9 (6.2).

Synthesis of TD880: In a glass vial (4 mL), TD650·1.1FA·1.6H₂O (35.0 mg; 49.8 μmol; 1.0 equiv.) was dissolved in aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.50 mL; 1.25 mmol; 25 equiv.) and aq. CdCl₂ (62.6 mM; 875 μL; 54.8 μmol; 1.1 equiv.) and the mixture was stirred 1 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with no additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 37.1 mg (90%; 1 step; based on TD650·1.1FA·1.6H₂O). NMR (D₂O, pD ˜7): ¹H δ_H 2.24-3.54 (mc, CH₂—CO, m, 16+4H); 3.60-3.79 (CH₂-arom., m, 2H); 4.03 (CH₂-arom., d, 1H, ²J_HH=13); 4.75 (CH₂-arom., d, 1H, ²J_HH=14); 5.51 (CH₂—N₃, d, 1H, ²J_HH=15); 6.95 (CH₂—N₃, d, 1H, ²J_HH=15); 7.58-7.67 (Ph, m, 3H); 7.71 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.80 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (arom., d, 1H, ⁴J_HH=2); 7.93-7.98 (Ph, m, 2H); 8.04 (CH—N₃, s, 1H); 8.15 (arom., t, 1H, ³J_HH=8); 8.21 (arom., d, 1H, ⁴J_HH=2); ¹³C{¹H} δ_C 47.8 (mc, s); 48.3 (mc, s); 49.3 (mc, s); 50.3 (mc, s); 50.9 (mc, s); 51.1 (mc, s); 51.2 (mc, s); 51.5 (mc, s); 53.4 (CH₂—N₃, s); 56.6 (CH₂—CO, s); 57.4 (CH₂-arom., s); 57.6 (CH₂—CO, s); 58.6 (CH₂-arom., s); 124.3 (arom., s); 125.2 (arom., s); 128.2 (Ph, s); 128.3 (arom., s); 128.9 (arom., s); 130.2 (Ph, s); 131.3 (Ph, s); 135.3 (CH—N₃, s); 136.6 (Ph, s); 138.8 (arom., s); 141.3 (arom., s); 147.4 (arom., s); 153.6 (arom., s); 156.9 (arom., s); 157.9 (arom., s); 158.3 (arom., s); 175.7 (CO, s); 177.4 (CO, s). ESI-HRMS: 738.2079 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Cd₁]⁺=738.2075). EA ([C₃₃H₃₇N₉O₄Cd₁]5.1H₂O, M_R=828.0): C 47.9 (47.6); H 5.7 (5.0); N 15.2 (14.6); Cd 13.6 (13.5).

Synthesis of TD863: In a glass vial (20 mL), TD650·1.1FA·1.6H₂O (8.2 mg; 11.7 μmol; 1.0 equiv.) was dissolved in H₂O (2 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.35 mL; 675 μmol; 58 equiv.) and aq. Ca(NO₃)₂(100 mM; 200 μL; 20 μmol; 1.7 equiv.) and the mixture was stirred 24 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with no additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 7.4 mg (81%; 1 step; based on TD650·1.1FA·1.6H₂O). NMR (D₂O, pD ˜6): ¹H δ_H 2.20-3.58 (mc, CH₂—CO, m, 16+4H); 3.62 (CH₂-arom., d, 1H, ²J_HH=14); 3.76 (CH₂-arom., d, 1H, ²J_HH=15); 4.09 (CH₂-arom., d, 1H, ²J_HH=14); 4.54 (CH₂-arom., d, 1H, ²J_HH=15); 5.56 (CH₂—N₃, d, 1H, ²J_HH=16); 7.02 (CH₂—N₃, d, 1H, ²J_HH=16); 7.57-7.65 (Ph, m, 3H); 7.66 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.72 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., d, 1H, ⁴J_HH=2); 7.89 (CH N₃, s, 1H); 7.90-7.95 (Ph, m, 2H); 8.09 (arom., t, 1H, ³J_HH=8); 8.12 (arom., d, 1H, ⁴J_HH=2); ¹³C{¹H} δ_C 48.4 (mc, s); 48.5 (mc, s); 50.6 (mc, s); 50.7 (mc, s); 52.6 (mc, s); 52.7 (mc, s); 53.0 (mc, s); 53.3 (CH₂—N₃, s); 53.6 (mc, s); 57.9 (CH₂—CO, s); 59.1 (CH₂-arom., s); 59.2 (CH₂-arom., s); 59.3 (CH₂—CO, s); 123.3 (arom., s); 124.7 (arom., s); 127.0 (arom., s); 128.1 (Ph, s); 128.2 (arom., s); 130.1 (Ph, s); 130.9 (Ph, s); 136.7 (CH—N₃, s); 137.3 (Ph, s); 139.4 (arom., s); 140.9 (arom., s); 146.7 (arom., s); 153.1 (arom., s); 155.5 (arom., s); 159.3 (arom., s); 159.5 (arom., s); 178.4 (CO, s); 179.7 (CO, s). ESI-HRMS: 664.2663 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Ca₁]⁺=664.2667). EA ([C₃₃H₃₇N₉O₄Ca₁]6.7H₂O, M_R=784.5): C 50.5 (50.5); H 6.5 (6.0); N 16.1 (15.6); Ca 5.1 (4.8).

Synthesis of TD1214: In a glass vial (20 mL), TD650·1.1FA·1.6H₂O (9.0 mg; 12.8 μmol; 1.0 equiv.) was dissolved in H₂O (780 μL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 650 μL; 325 μmol; 25 equiv.) and aq. Na₂[PdCl₄](25 mM; 570 μL; 14.3 μmol; 1.1 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 6.4 mg (58%; 1 step; based on TD650·1.1FA·1.6H₂O). NMR (D₂O, pD ˜5): 1.54-3.82 (mc, CH₂—CO, bm, 16+4H); 4.21-5.10 (CH₂-arom., bm, 4H overlapped with water signal); 5.69 (CH₂—N₃, bs, 1H); 7.42-7.54 (Ph, arom., m, 3+1H); 7.60 (arom., d, 1H, ³J_HH=8); 7.65 (CH₂—N₃, bs, 1H); 7.69-7.76 (Ph, m, 2H); 8.01 (arom., d, 1H, ³J_HH=8); 8.08-8.15 (arom., m, 2H); 8.47 (CH—N₃, s, 1H). ESI-HRMS: 730.2088 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Pd₁]⁺=730.2076). EA ([C₃₃H₃₇N₉O₄Pd₁]·0.2FA·7.0H₂O, M_R=865.2): C 46.1(46.4); H 6.0 (5.7); N 14.6 (14.4); Pd 12.3 (9.6).

Synthesis of TD876: In a glass vial (20 mL), TD650·1.1FA·1.6H₂O (8.2 mg; 11.7 μmol; 1.0 equiv.) was dissolved in H₂O (2.5 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 580 μL; 290 μmol; 25 equiv.) and aq. Pb(NO₃)₂(52.4 mM; 300 μL; 15.7 μmol; 1.3 equiv.) and the mixture was stirred 5 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with no additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 10.4 mg (94%; 1 step; based on TD650·1.1FA·1.6H₂O). NMR (D₂O, pD ˜6): SH 2.40-3.62 (mc, CH₂—CO, bm, 16+4H); 4.20 (CH₂-arom., bm, 4H); 5.72 (CH₂—N₃, bd, 1H, ²J_HH=15); 6.18 (CH₂—N₃, bd, 1H, ²J_HH=15); 7.56-7.67 (Ph, in, 3H); 7.74 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.79 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86-7.90 (Ph, in, 2H); 7.91 (arom., d, 1H, ⁴J_HH=2); 7.99 (CH—N₃, s, 1H); 8.08 (arom., d, 1H, ⁴J_HH=2); 8.16 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 832.2806 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Pb₁]⁺=832.2808). EA ([C₃₃H₃₇N₉O₄Pb₁]·6.4H₂O, M_R=946.2): C 41.9 (42.6); H 5.3 (4.7); N 13.3 (12.6); Pb 21.9 (21.4).

Synthesis of TD1238: Synthesis: In a glass vial (20 mL), TD1188·0.2TFA·0.4FA·4.3H₂O (6.5 mg; 8.6 μmol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 950 μL; 475 μmol; 56 equiv.) and solid Tl(NO₃)₃·3H₂O (4.2 mg; 9.5 μmol; 1.1 equiv.) and the mixture was stirred 2 h at 80° C. Then, another portion of Tl(NO₃)₃·3H₂O (19.0 mg; 43 μmol; 5.0 equiv.) was added and the mixture was further stirred 20 h at 80° C. Mixture was then filtered through syringe microfilter (RC) and the filtrate was evaporated to dryness. Residue was re-dissolved in H₂O and directly purified by preparative (HPLC C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white solid. Yield: 1.4 mg (≤18% assuming [M]⁺[TFA]⁻·xH₂O; M_R=933.0; 1 step; based on TD1188·0.2TFA·0.4FA·4.3H₂O). NMR (D₂O, pD ˜4, two set of signals on ¹H, but one on ¹⁹F): SH 2.17-5.34 (mc, CH₂—CO, CH₂-arom., m, 16+4H+4H); 5.54-5.70 (CH₂—N₃, m, 1H); 6.93-7.07 (CH₂—N₃, m, 1H); 7.69-8.44 (arom., m, 6H). ¹⁹F δ_F −58.70 (s). ESI-HRMS: 820.2265 [M]⁺ (theor. [C₂₈H₃₂N₉O₄F₃Tl₁]⁺=820.2264).

Synthesis of TD735: In a glass vial (20 mL), TD722·0.7TFA·2.0H₂O (100 mg; 130 μmol; 1.0 equiv.) was dissolved in H₂O (30 mL) followed by 27 equiv.) and aq. LuCl₃ (100 mM; 1.50 mL; 150 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 134.2 mg (91%; 1 step; based on TD722·0.7TFA·2.0H₂O). NMR (D₂O, pD ˜4): ¹H δ_H 2.65-3.84 (mc, CH₂—CO, m, 16+4H); 4.01 (CH₂-arom., d, 1H, ²J_HH=15); 4.04 (CH₂—NH₂, d, 1H, ²J_HH=15); 4.23 (CH₂-arom., d, 1H, ²J_HH=16); 4.31 (CH₂—NH₂, d, 1H, ²J_HH=15); 4.33 (CH₂-arom., d, 1H, ²J_HH=15); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 5.68 (CH₂—N₃, d, 1H, ²J_HH=15); 7.08 (CH₂—N₃, d, 1H, ²J_HH=15); 7.60-7.69 (Ph, m, 3H); 7.72 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.91 (arom., dd, 1H, ³J_HH=8, ^4HJ_HH=1); 7.92-7.99 (Ph, m, 2H); 8.03 (arom., d, 1H, ⁴J_HH=2); 8.31 (arom., t, 1H, ³J_HH=8); 8.33 (arom., d, 1H, ⁴J_HH=2). ¹³C{¹H} δ_C 34.8 (CH₂—C≡C, s); 48.9 (mc, s); 49.2 (mc, s); 51.8 (mc, s); 52.0 (mc, s); 53.4 (CH₂—N₃, s); 53.9 (mc, s); 54.1 (mc, s); 55.2 (mc, s); 56.1 (mc, s); 59.2 (CH₂—CO, s); 59.7 (CH₂-arom., s); 60.0 (CH₂-arom., s); 61.1 (CH₂—CO, s); 124.0 (arom., s); 126.8 (arom., s); 128.2 (arom., s); 128.4 (Ph, s); 130.3 (Ph, s); 130.8 (arom., s); 131.9 (Ph, s); 136.0 (Ph, s); 136.2 (arom, s); 140.5 (arom., s); 142.8 (arom., s); 144.4 (arom., s); 155.0 (arom., s); 156.0 (arom., s); 158.9 (arom., s); 160.0 (arom., s); 170.7 (FA, s); 178.8 (CO, s); 179.3 (CO, s). ESI-HRMS: 827.2637 [M](theor. [C₃₄H₄₀N₁₄O₄Lu₁]⁺=827.2636). EA ([C₃₄H₄₀N₁₀O₄Lu₁]⁺[TFA]⁻·1.2TFA·3.1H₂O, M_R=1133.3): C 40.7 (40.9); H 4.2 (3.9); N 12.4 (12.1); Lu 11.1 (11.0).

Synthesis of TD1059: In a glass vial (20 mL), TD1054·0.3TFA·0.8FA·2.3H₂O (10.0 mg; 12.9 μmol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 800 μL; 400 μmol; 31 equiv.) and aq. LuCl₃ (100 mM; 150 μL; 15.0 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 10.8 mg (71%; 1 step; based on TD1054·0.3TFA·0.8FA·2.3H₂O). NMR (D₂O, pD ˜6): ¹H δ_H1.18 (CH₃, s, 3H); 1.79 (CH₃, s, 3H); 2.64-3.85 (mc, CH₂—CO, m, 16+4H); 4.03 (CH₂-arom., d, 1H, ²J_HH=15); 4.30 (CH₂-arom., d, 1H, ²J_HH=16); 4.36 (CH₂-arom., d, 1H, ²J_HH=18); 4.86 (CH₂-arom., d, 1H, ²J_HH=18); 5.62 (CH₂—N₃, d, 1H, ²J_HH=15); 6.83 (CH₂—N₃, d, 1H, ²J_HH=15); 7.60-7.68 (Ph, m, 3H); 7.83 (arom., d, 1H, ³J_HH=8); 7.89 (arom., d, 1H, ³J_HH=8); 7.91-7.98 (Ph, m, 2H); 8.03 (arom., d, 1H, ⁴J_HH=2); 8.28 (arom., t, 1H, ³J_HH=8); 8.30 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 855.2951 [M]⁺ (theor. [C₃₆H₄₄N₁₀O₄Lu₁]⁺=855.2949). EA ([C₃₇H₄₅N₁₀O₄Lu₁]⁺[TFA]⁻·1.0TFA·4.6H₂O, M_R=1178.6): C 41.8 (41.4); H 4.7 (4.2); N 11.9 (11.7); Lu 14.8 (13.2).

Synthesis of TD1124: In a glass vial (20 mL), TD1105·0.1FA·2.0H₂O (35.2 mg; 47.1 mol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.35 mL; 1.18 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 520 μL; 52.0 μmol; 1.1 equiv.) and the mixture was stirred 4 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 41.2 mg (77%; 1 step; based on TD1105·0.1FA·2.0H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.17 (CH₃, s, 3H); 1.78 (CH₃, s, 3H); 2.64-3.84 (mc, CH₂—CO, m, 16+4H); 3.97 (CH₂-arom., d, 1H, ²J_HH=15); 4.25 (CH₂-arom., d, 1H, ²J_HH=15); 4.35 (CH₂-arom., d, 1H, ²J_HH=17); 4.86 (CH₂-arom., d, 1H, ²J_HH=17); 5.56 (CH₂—N₃, d, 1H, ²J_HH=15); 6.80 (CH₂—N₃, d, 1H, ²J_HH=15); 7.73 (arom., d, 1H, ³J_HH=8); 7.82 (arom., d, 1H, ³J_HH=8); 7.88 (arom., d, 1H, ³J_HH=8); 7.99 (arom., d, 1H, ³J_HH=8); 8.24 (arom., t, 1H, ³J_HH=8); 8.27 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 779.2636 [M]⁺ (theor. [C₃₀H₄₀N₁₀O₄Lu₁]⁺=779.2636). EA ([C₃₀H₄₀N₁₀O₄Lu₁]⁺[TFA]⁻·1.5TFA·3.9H₂O, M_R=1133.9): C 37.1 (37.3); H 4.4 (3.9); N 12.4 (12.0); F 12.6 (12.1).

Synthesis of TD1137: In a glass vial (20 mL), TD1127·1.8TFA·0.1FA·(45.9 mg; 52.2 μmol; 1.0 equiv.) was dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.15 mL; 1.58 mmol; 30 equiv.) and aq. LuCl₃ (100 mM; 690 μL; 69.0 μmol; 1.3 equiv.) and the mixture was stirred 2 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 58.2 mg (98%; 1 step; based on TD1127·1.8TFA·0.1FA). NMR (D₂O, pD ˜4): ¹H δ_H 1.92-2.13 (CH₂, m, 3H); 2.17-2.33 (CH₂, m, 1H); 2.63-3.83 (mc, CH₂—CO, CH₂, CH, m, 16+4+4+1H); 3.98 (CH₂-arom., d, 1H, ²J_HH=15); 4.22 (CH₂-arom., d, 1H, ²J_HH=15); 4.34 (CH₂-arom., d, 1H, ²J_HH=17); 4.87 (CH₂-arom., d, 1H, ²J_HH=17); 5.50 (CH₂—N₃, d, 1H, ²J_HH=15); 6.93 (CH₂—N₃, d, 1H, ²J_HH=15); 7.67-7.76 (arom., m, 2H); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.98 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.23 (arom., t, 1H, ³J_HH=8); 8.27 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 805.2786 [M]⁺ (theor. [C₃₂H₄₂N₁₀O₄Lu₁]⁺=805.2793). EA ([C₃₂H₄₂N₁₀O₄Lu₁]⁺[TFA]·1.0TFA·5.5H₂O, M_R=1131.8): C 38.2 (38.7); H 4.8 (4.5); N 12.4 (11.9); F 10.1 (9.9).

Synthesis of TD1182: In a glass vial (20 mL), TD1176·0.8FA·4.4H₂O (39.3 mg; 55.4 μmol; 1.0 equiv.) was dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.77 mL; 1.39 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 610 μL; 61.0 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 44.8 mg (77%; 1 step; based on TD1176·0.8FA·4.4H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.55-3.78 (mc, CH₂—CO, CH₃, CH₂-arom., m, 16+4+6+2H); 4.11 (CH₂-arom., d, 1H, ²J_HH=16); 4.13 (CH₂-arom., d, 1H, ²J_HH=14); 5.31 (CH₂—N₃, d, 1H, ²J_HH=15); 6.73 (arom., d, 1H, ⁴J_HH=2); 6.83 (CH₂—N₃, d, 1H, ²J_HH=15); 7.07 (arom., d, 1H, ⁴J_HH=2); 7.78 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.89 (CH—N₃, s, 1H); 8.22 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 765.2487 [M]⁺ (theor. [C₂₉H₃₉N₁₀O₄Lu₁]⁺=765.2486). EA ([C₂₉H₃₈N₁₀O₄Lu₁]⁺[TFA]⁻·1.0TFA·3.4H₂O, M_R=1053.9): C 37.6 (37.5); H 4.4 (4.1); N 13.3 (13.1); F 10.8 (10.5).

Synthesis of TD1152: In a glass vial (20 mL), TD1148·0.1FA·1.0H₂O (27.0 mg 41.0 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.05 mL; 1.03 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 450 μL; 45.0 μmol; 1.1 equiv.) and the mixture was stirred 3 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 24.5 mg (60%; 1 step; based on TD1148·0.1FA·1.0H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.43 (CH₃, d, 6H, ³J_HH=6); 2.65-3.85 (mc, CH₂—CO, m, 16+4H); 4.06 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.34 (CH₂-arom., d, 1H, ²J_HH=15); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 5.34 (CH, hept, 1H, ³J_HH=6); 5.69 (CH₂—N₃, d, 1H, ²J_HH=15); 7.17 (CH₂—N₃, d, 1H, ²J_HH=15); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH N₃, S, 1H); 8.22 (arom., d, 1H, ⁴J_HH=2); 8.25 (arom., t, 1H, ³J_HH=8); 8.53 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 808.2425 [M]⁺ (theor. [C₃₁H₃₉N₉O₆Lu₁]⁺=808.2426). EA ([C₃₁H₃₉N₉O₆Lu₁]⁺[TFA]⁻·0.3TFA·2.5H₂O, M_R=1000.9): C 40.3 (40.7); H 4.5 (4.2); N 12.6 (12.2); F 7.4 (7.6).

Synthesis of TD1123: In a glass vial (20 mL), TD1092·0.1FA·1.1H₂O (25.9 mg; 41.0 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.05 mL; 1.03 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 450 μL; 45.0 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 24.7 mg (60%; 1 step; based on TD1092·0.1FA·1.1H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.65-3.86 (mc, CH₂—CO, m, 16+4H); 4.09 (CH₂-arom., d, 1H, ²J_HH=15); 4.18 (CH₂-arom., d, 1H, ²J_HH=16); 4.36 (CH₂-arom., d, 1H, ²J_HH=15); 4.87 (CH₂-arom., d, 1H, ²J_HH=16); 5.73 (CH₂—N₃, d, 1H, ²J_HH=15); 7.19 (CH₂—N₃, d, 1H, ²J_HH=15); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH N₃, s, 1H); 8.21 (arom., d, 1H, ⁴J_HH=2); 8.27 (arom., t, 1H, ³J_HH=8); 8.50 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 766.1948 [M]⁺ (theor. [C₂₈H₃₃N₉O₆Lu₁]⁺=766.1956). EA ([C₂8H₃₃N₉O₆Lu₁]⁺[TFA]⁻·0.6TFA·3.6H₂O, M_R=1012.8): C 37.0 (36.7); H 4.1(3.6); N 12.4 (12.0); F 9.0 (8.6).

Synthesis of TD897: In a glass vial (20 mL), TD742·0.1FA·3.2H₂O (48.6 mg; 66.4 μmol; 1.0 equiv.) was dissolved in H₂O (15 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 3.4 mL; 1.70 mmol; 26 equiv.) and aq. TmCl₃ (100 mM; 800 μL; 80.0 μmol; 1.2 equiv.) and the mixture was stirred 8 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 65.2 mg (88%; 1step; based on TD742·0.1FA·3.2H₂O). ESI-HRMS: 836.2206 [M]⁺ (theor. [C₃₄H₃₇N₉O₆Tm₁]⁺=836.2203). EA ([C₃₄H₄₀N₁₀O₄Tm₁]⁺[TFA]⁻·1.1TFA·2.6H₂O, M_R=1121.9): C 40.9 (40.9); H 3.9 (3.8); N 11.2 (11.2); Tm 15.1 (15.2); F 10.7 (10.7).

Synthesis of TD748: In a glass vial 20 mL), TD742·0.2FA·1.6H₂O (85 mg; 120 μmol; 1.0 equiv.) was

dissolved in H₂O (12 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 6.00 mL; 3.00 mmol; 25 equiv.) and aq. LuCl₃ (100 mM; 1.3 mL; 130 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 105 mg (75%; 1step; based on TD742·0.1FA·2.9H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.64-3.86 (mc, CH₂—CO, m, 16+4H); 3.98 (CH₂-arom., d, 1H, ²J_HH=15); 4.18 (CH₂-arom., d, 1H, ²J_HH=16); 4.34 (CH₂-arom., d, 1H, ²J_HH=15); 4.87 (CH₂-arom., d, 1H, 2J_HH=16); 5.71 (CH₂—N₃, d, 1H, 2J_HH=15); 7.17 (CH₂—N₃, d, 1H, 2J_HH 15); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.92 (arom., d, 1H, ⁴J_HH=2); 7.94 (CH N₃, s, 1H); 7.97 (arom., dm, 2H, ³J_HH=9); 8.15 (arom., dm, 2H, ³J_HH=9); 8.27 (arom., t, 1H, ³J_HH=8); 8.43 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 842.2259 [M]⁺ (theor. [C₃₄H₃₇N₉O₆Lu₁]⁺=842.2269).EA ([C₃₄H₄₀N₁₀O₄Lu₁]⁺[TFA]⁻·1.4TFA·3.2H₂O, M_R=1172.9): C 39.7 (40.0); H 3.9 (3.5); N 10.7 (10.3); Lu 14.9 (14.9); F 11.7 (11.8).

Synthesis of TD785: In a glass vial (20 mL), TD742·0.1FA·2.9H₂O (13 mg; 18 μmol; 1.0 equiv.) was

dissolved in H₂O (18 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.20 mL; 600 μmol; 31 equiv.) and aq. YCl₃ (100 mM; 197 μL; 20 μmol; 1.1 equiv.) and the mixture was stirred 22 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 13 mg (71%; 1step; based on TD742·0.1FA·2.9H₂O). NMR (D₂O, pD ˜2): ¹H δ_H 2.60-3.88 (mc, CH₂—CO, m, 16+4H); 3.98 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.38 (CH₂-arom., d, 1H, ²J_HH=15); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 5.94 (CH₂—N₃, d, 1H, ²J_HH=16); 7.09 (CH₂—N₃, d, 1H, ²J_HH=16); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.91 (CH N₃, s, 1H); 7.98 (arom., d, 1H, ⁴J_HH=2); 8.00 (arom., dm, 2H, ³J_HH=9); 8.02 (arom., dm, 2H, ³J_HH=9); 8.26 (arom., t, 1H, ³J_HH=8); 8.40 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 756.1925 [M]⁺ (theor. [C₃₄H₃₇N₉O₆Y₁]⁺=756.1920). EA ([C₃₄H₃₇N₉O₆Y₁]⁺[TFA]⁻·0.6TFA·4.8H₂O, M_R=1024.5): C 43.6 (43.9); H 4.6 (4.2); N 12.3 (12.0); Y 8.7 (7.9); F 8.9 (8.5).

Synthesis of TD904: In a glass vial (20 mL), TD744·1.0TFA·1.3H₂O (38.6 mg; 46.2 μmol; 1.0 equiv.) was dissolved in H₂O (16 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.80 mL; 1.40 mmol; 30 equiv.) and aq. LuCl₃ (100 mM; 550 μL; 55.0 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 42.2 mg (75%; 1 step; based on TD744·1.0TFA·1.3H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.62-3.87 (mc, CH₂—CO, m, 16+4H); 4.03 (CH₂—NH₂, d, 1H, ²J_HH=15); 4.05 (CH₂-arom., d, 1H, ²J_HH=15); 4.24 (CH₂-arom., d, 1H, ²J_HH=16); 4.32 (CH₂—NH₂, d, 1H, ²J_HH=15); 4.35 (CH₂-arom., d, 1H, ²J_HH=15); 4.87 (CH₂-arom., d, 1H, ²J_HH=16); 5.71 (CH₂—N₃, d, 1H, ²J_HH=15); 7.10 (CH₂—N₃, d, 1H, ²J_HH=15); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.92 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.03 (arom., dm, 2H, ³J_HH=9); 8.07 (arom., d, 1H, ⁴J_HH=2); 8.21 (arom., dm, 2H, ³J_HH=9); 8.31 (arom., t, 1H, ³J_HH=8); 8.40 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 871.2536 [M]⁺ (theor. [C₃₅H₄₀N₁₀O₆Lu₁]⁺=471.2535). EA ([C₃₅H₄₀N₁₀O₆Lu₁]⁺[TFA]⁻·1.1TFA·6.0H₂O, M_R=1218.2): C 38.6 (38.6); H 4.4 (4.1); N 11.5 (11.2); F 9.8 (9.5).

Synthesis of 905: In a glass vial (2 mL), [TD904]⁺[TFA]⁻·1.1TFA·6.0H₂O (10.0 mg; 8.2 μmol; 1.0 equiv.) was dissolved in aq. Borate/NaOH buffer (200 mM; pH 9.0; 2.00 mL; 400 mmol; 50 equiv.). followed by addition of freshly prepared solution of FmocCl (3.3 mg; 12.8 μmol; 1.6 equiv.) in MeCN (1.5 mL). The resulting clear solution was stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 9.8 mg (≤99% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1207.0; 1step; based on [TD904]⁺[TFA]⁻·1.1TFA·6.0H₂O). NMR (CD₃CN; compound is soluble in D₂O but shows broad ¹H signals): ¹H δ_H 2.52-3.64 (mc, CH₂—CO, m, 16+4H); 3.89 (CH₂-arom., d, 1H, ²J_HH=15); 4.03 (CH₂—NH-Fmoc, dd, 1H, ²J_HH=15, ³J_HH=3); 4.05 (CH₂-arom., d, 1H, ²J_HH=16); 4.18 (Fmoc, t, 1H, ³J_HH=7); 4.26-4.35 (Fmoc, m, 2H); 4.36 (CH₂-arom., d, 1H, ²J_HH=15); 4.52 (CH₂—NH-Fmoc, dd, 1H, ²J_HH=15, ³J_HH=7); 4.78 (CH₂-arom., d, 1H, ²J_HH=16); 5.50 (CH₂—N₃, d, 1H, ²J_HH=15); 6.54 (NH-Fmoc, dd, 1H, ³J_HH=7, ³J_HH=3); 7.27-7.33 (Fmoc, m, 2H); 7.35-7.43 (Fmoc, CH₂—N₃, m, 2+1H); 7.57-7.65 (Fmoc, CH₂-arom., m, 2+1H); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.78-7.84 (Fmoc, m, 2H); 7.91 (arom., d, 1H, ⁴J_HH=2); 7.97 (arom., dm, 2H, ³J_HH=9); 8.14 (arom., t, 1H, ³J_HH 8); 8.18 (arom., dm, 2H, ³J_HH=9); 8.26 (arom., d, 1H, ⁴J_HH=2). ESI-HRMS: 1093.3219 [M]⁺ (theor. [C₅₀H₅₀N₁₀O₈Lu₁]⁺=1093.3215).

Synthesis of TD757: In a glass vial (2 mL), [TD748]⁺[FA]⁻·6.4H₂O (0.7 mg; 0.7 μmol; 1.0 equiv.) was dissolved in DMSO (75 μL) followed by addition of 4-Fluoro-L-phenylalanine hydrochloride (50 mm in DMSO; 22 μL; 1.1 μmol; 1.5 equiv.), DIPEA (100 mm in DMSO; 22 μL; 2.2 μmol; 3.1 equiv.) and HATU (freshly prepared 50 mM in DMSO; 24 μL; 1.2 μmol; 1.7 equiv.) and the resulting yellow solution was stirred 5 min at RT. Mixture was then diluted with H₂O (750 μL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 0.7 mg (≤90% assuming [M]⁺[FA]⁻·xH₂O; M_R=1066.9; 1 step; based on [TD748]⁺[FA]⁻·6.4H₂O). NMR (D₂O, pD ˜4): ¹H δ_H 2.56-3.79 (mc, CH₂—CO, CH₂—CH, m, 16+4+2H); 3.82 (CH₃, s, 3H); 4.02 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.35 (CH₂-arom., d, 1H, ²J_HH=15); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 4.96 (CH₂—CH, dd, 1H, ³J_HH=10, ³J_HH=5); 5.68 (CH₂—N₃, d, 1H, ²J_HH=15); 7.04-7.20 (CH₂—N₃, arom., m, 1+2H); 7.27-7.34 (arom., dd, 2H, ³J_HF=9, ³J_HH=6); 7.78-7.88 (arom., m, 4H); 7.90 (CH—N₃, s, 1H); 7.95-8.06 (arom., m, 3H); 8.26 (arom., t, 1H, ³J_HH=8); 8.35 (arom., d, 1H, ⁴J_HH=2); 8.46 (FA, s, 1H). ¹⁹F δ_F −116.5 (tt, ³J_FH=9, ⁴J_FH=5). ESI-HRMS: 1021.3014 [M]⁺ (theor. [C₄₄H₄₇N₁₀O₇F₁Lu₁]⁺=1021.3015).

Synthesis of TD793: In a glass vial (2 mL), [TD782]⁺[TFA]⁻·5.1H₂O (4.4 mg; 4.6 μmol; 1.0 equiv.) was dissolved in DMSO (460 μL) followed by addition of N-Boc-cysteine (50 mM in DMSO; 185 μL; 9.3 μmol; 2.0 equiv.) and DIPEA (8 μL; 46 μmol; 10 equiv.) and the resulting solution was stirred 16 h RT. Mixture was then diluted with H₂O (2 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 2.0 mg (≤41% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1054.8; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.28-1.54 (CH₃, m, 9H); 2.63-3.95 (mc, CH₂—CO, CH₂—S, CH₂-arom., m, 16+4+2+1H); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.26 (CH₂-arom., d, 1H, ²J_HH=15); 4.48-4.63 (NH—CH—COOH, m, 1H); 4.84 (CH₂-arom., d, 1H, ²J_HH=16); 5.45-5.59 (CH₂—N₃, m, 1H); 7.03 (CH₂—N₃, d, 1H, ²J_HH=15); 7.59-7.65 (arom., m, 1H); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 7.90-7.95 (arom., m, 1H); 8.26 (arom., t, 1H, ³J_HH=8). ESI-HRMS: 941.2614 [M]⁺ (theor. [C₃₅H₄₆N₁₀O₈S₁Lu₁]⁺=941.2623).

Synthesis of TD875: In a glass vial (20 mL), TD871·0.6FA·2.3H₂O (10.0 mg; 14.4 μmol; 1.0 equiv.) was dissolved in H₂O (2 mL) followed by addition of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 750 μL; 375 μmol; 26 equiv.) and aq. GdCl₃ (100 mM; 180 μL; 18.0 μmol; 1.3 equiv.). The resulting suspension was stirred 20 d at 80° C. Then, the mixture was diluted with additional H₂O (16 mL) followed by another portion of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 750 μL; 375 μmol; 26 equiv.) and aq. GdCl₃ (100 mM; 180 μL; 18.0 μmol; 1.3 equiv.). The resulting suspension was further stirred 10 d at 80° C. Mixture was the filtered through syringe microfilter (RC). The filtrate was evaporated to dryness and then resuspended in H₂O (3.6 mL). Mixture was once more filtered through syringe microfilter (RC) and the filtrate was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 2.1 mg (≤18% assuming [M]⁺[FA]⁻·xH₂O; M_R=826.0; 1 step; based on TD871·0.6FA·2.3H₂O). ESI-HRMS: 781.2205 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Gd₁]⁺=781.2204).

Synthesis of TD874: In a glass vial (20 mL), TD871·0.6FA·2.3H₂O (10.0 mg; 14.4 μmol; 1.0 equiv.) was dissolved in H₂O (2 mL) followed by addition of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 750 μL; 375 μmol; 26 equiv.) and aq. LuCl₃ (100 mM; 180 μL; 18.0 μmol; 1.3 equiv.). The resulting suspension was stirred 20 d at 80° C. Then, the mixture was diluted with additional H₂O (16 mL) followed by another portion of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 750 μL; 375 μmol; 26 equiv.) and aq. LuCl₃ (100 mM; 180 μL; 18.0 μmol; 1.3 equiv.). The resulting suspension was further stirred 10 d at 80° C. Mixture was the filtered through syringe microfilter (RC). The filtrate was evaporated to dryness and then resuspended in H₂O (3.6 mL). Mixture was once more filtered through syringe microfilter (RC) and the filtrate was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 8.6 mg (≤71% assuming [M]⁺[FA]⁻·xH₂O; M_R=843.2; 1 step; based on TD871·0.6FA·2.3H₂O). NMR (D₂O, pD ˜6): ¹H δ_H 2.13-3.76 (mc, CH₂—CO, CH₂-arom., m, 16+3+1H); 4.13 (CH₂—CO, d, 1H, ²J_HH=18); 4.32 (CH₂-arom., d, 1H, ²J_HH=16); 4.45 (CH₂-arom., d, 1H, ²J_HH=16); 4.67 (CH₂-arom., d, 1H, ²J_HH=13); 5.81 (CH₂— N₃, d, 1H, ²J_HH=14); 6.08 (CH₂— N₃, d, 1H, ²J_HH=14); 7.56-7.64 (Ph, arom., m, 3+1H); 7.67 (arom., d, 1H, ⁴J_HH=2); 7.79-7.85 (Ph, m, 2H); 7.90 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.09 (arom., d, 1H, ⁴J_HH=2); 8.16 (arom., t, 1H, ³J_HH 8); 8.45 (FA, s, 1H); 8.72 (CH N₃, s, 1H). ESI-HRMS: 798.2376 [M]⁺ (theor. [C₃₃H₃₇N₉O₄Lu₁]⁺=798.2371).

Synthesis of TD900: In a glass vial (4 mL), TD871·0.6FA·2.3H₂O (4.3 mg; 6.2 μmol; 1.0 equiv.) was dissolved in aq. MOPS/NaOH buffer (500 mM; pH 7.0; 640 μL; 320 μmol; 52 equiv.) and aq. CdCl₂ (62.6 mM; 120 μL; 7.5 μmol; 1.2 equiv.) and the mixture was stirred 1 h at 80° C. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with no additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 4.2 mg (≤92% assuming [M]·xH₂O; M_R=736.1; 1 step; based on TD871·0.6FA·2.3H₂O). NMR (D₂O, pD ˜7): ¹H δ_H 2.00-4.41 (mc, CH₂—CO, CH₂-arom., bm, 16+4+4H); 5.93 (CH₂—N₃, bs, 2H); 7.44 (arom., dd, 1H, ³J_HH8, ⁴J_HH=1); 7.53-7.63 (Ph, m, 3H); 7.73-7.84 (Ph, arom., m, 2+1H); 7.88-7.96 (arom., m, 2H); 8.01 (arom., t, 1H, ³J_HH=8); 9.74 (CH N₃, s, 1H. ESI-HRMS: 738.2081 [M+H]⁺ (theor. [C₃₃H₃₈N₉O₄Cd₁]⁺=738.2075).

Synthesis of TD685: In a glass vial (20 mL), TD669·0.1FA·xH₂O (17 mg; ˜27 μmol; 1.0 equiv.) was dissolved in H₂O (17 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 2.10 mL; 1.05 mmol; ˜40 equiv.) and aq. YCl₃ (100 mM; 290 μL; 29 μmol; ˜1.1 equiv.) and the mixture was stirred 6 weeks at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 4 mg (≤21% assuming [M]⁺[FA]⁻·xH₂O; M_R=761.7; 1 step; based on TD669·0.1FA·xH₂O). NMR (D₂O, pD ˜5): ¹H SH 2.63-3.09 (mc, CH₂—CH₂—N—CH₂—C≡CH, m, 4+2H); 3.11 (C≡CH, t, 1H, ⁴J_HH=2); 3.13-3.75 (mc, CH₂—CH₂—N—CH₂—C—CH, CH₂—CO, 12+2+2H); 3.78 (CH₂—CO, d, 1H, ²J_HH=19); 3.79 (CH₂—C—CH, dm, 1H, ²J_HH=18); 3.91 (CH₂—C≡CH, dd, 1H, ²J_HH=18, ⁴J_HH=2); 4.01 (CH₂—CO, d, 1H, ²J_HH=19); 4.09 (CH₂-arom., d, 1H, ²J_HH=15); 4.25 (CH₂-arom., d, 1H, ²J_HH=15); 4.39 (CH₂—C—N₃, d, 1H, ²J_HH=15); 4.75 (CH₂—C—N₃, d, 1H, ²J_HH=15); 5.67 (CH₂—N₃, d, 1H, ²J_HH=15); 7.00 (CH₂—N₃, d, 1H, ²J_HH=15); 7.67-7.73 (Ph, m, 3H); 7.94 (arom., d, 1H, ⁴J_HH=2); 7.96-8.00 (Ph, m, 2H); 8.13 (CH—N₃, s, 1H); 8.30 (arom., d, 1H, ⁴J_HH=2); 8.52 (FA, s, 1H). ¹³C{¹H} δ_C 41.2 (CH₂—C—CH, s); 47.8 (CH₂—C—N₃, s); 52.6 (CH₂—CH₂—N—CH₂—C—CH, s); 54.1 (CH₂—CH₂—N—CH₂—C—CH, s); 54.4 (CH₂—N₃, s); 55.1 (mc, s); 57.2 (mc, s); 58.0 (mc, s); 59.0 (mc, s); 59.4 (mc, s); 59.5 (mc, s); 59.9 (mc, s); 60.1 (mc, bs); 66.0 (CH₂—CO, s); 67.2 (CH₂—CO, s); 67.6 (CH₂-arom., s); 75.3 (C≡CH, s); 81.8 (C≡CH, s); 124.8 (arom., s); 127.7 (arom., s); 130.0 (Ph, s); 132.1 (Ph, s); 133.6 (Ph, s); 143.4 (arom., s); 137.5 (Ph, s); 138.1 (CH—N₃, s); 156.1 (arom., s); 158.6 (arom., s); 161.4 (arom., s); 173.3 (FA, s); 181.2 (CO, s); 181.5 (CO, s). ESI-HRMS: 716.2327 [M]⁺ (theor. [C₃₃H₄₁N₉O₄Y₁]⁺=716.2335).

Synthesis of TD780: In a glass vial (4 mL), [TD685]⁺[FA]⁻·xH₂O (3 mg; ˜4 μmol; 1.0 equiv.) was dissolved in aq. MES/NaOH buffer (500 mM; pH 5.2; 375 μL; 188 μmol; ˜50 equiv.) followed by addition of t-BuOH (240 μL), Benzyl azide (500 mM in t-BuOH; 12 μL; 6 μmol; ˜1.6 equiv.) and aq. solution of CuSO₄ (500 mm; 3 μL; 1.5 μmol; ˜0.4 equiv.). To the resulting faint light blue solution was added freshly prepared aq. solution of Sodium ascorbate (100 mM; 15 μL; 1.5 μmol; ˜0.4 equiv.) and the color of the solution immediately changed to yellow-green. Mixture was stirred 1 h at RT after which was diluted with H₂O (2.4 mL) and filtered through syringe microfilter (RC). The filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 3 mg (≤74% assuming [M]⁺[TFA]⁻·xH₂O; M_R=962.8; 1 step; based on TD685·xH₂O). NMR (D₂O, pD ˜3): ¹H δ_H 2.46-4.59 (mc, CH₂—CO, CH₂-arom., CH₂—CH₂—N—(CH₂—C≡C)₂, m, 16+4+2+8H); 5.60 (CH₂—N₃, d, 1H, ²J_HH=16); 5.71 (CH₂-Ph, s, 2H); 6.94 (CH₂—N₃, d, 1H, ²J_HH=15); 7.37-7.50 (Ph, m, 5H); 7.59-7.65 (Ph, m, 3H); 7.88 (arom., d, 1H, ⁴J_HH=2); 7.89-7.93 (Ph, m, 2H); 8.21 (arom., d, 1H, ⁴J_HH=2); 8.34 (CH—N₃, s, 1H); 8.35 (CH—N₃, s, 1H). ESI-HRMS: 849.2970 [M]⁺ (theor. [C₄₀H₄₈N₁₂O₄]⁺=849.2975).

Synthesis of 1,4-TD1413: In a glass vial (20 mL), TD1408·0.1FA·2.4H₂O (10.0 mg; 16.4 μmol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 820 μL; 410 μmol; 25 equiv.) and aq. LuCl₃ (100 mM; 196 μL; 19.6 μmol; 1.2 equiv.). The resulting suspension was stirred 1 w at 80° C. Mixture was the filtered through syringe microfilter (RC). The filtrate was evaporated to dryness and the residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 9.3 mg (≤73% assuming [M]⁺[FA]⁻·xH₂O; M_R=781.6; 1 step; based on TD1408·0.1FA·2.4H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 1.73-3.16 (mc, CH₂—CO, m, 12+1H); 3.27 (CH₂—CO, d, ²J_HH=13); 3.42-3.77 (mc, CH₂—CH₂—N₃, CH₂—CO, m, 4+2+1H); 4.03 (CH₂—CH₂—N₃, ddd, 1H, ²J_HH=14, ³J_HH=12, ³J_HH=16); 4.10 (CH₂-arom., d, 1H, ²J_HH=17); 4.19 (CH₂-arom., d, 1H, ²J_HH=16); 4.34 (CH₂-arom., d, 1H, ²J_HH=16); 4.56 (CH₂—CO, d, 1H, ²J_HH=13); 4.92-5.03 (CH₂—CH₂—N₃, CH₂-arom., m, 1+1H); 7.18 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.54-7.60 (arom., m, 2H); 7.71-7.77 (arom., m, 2H); 8.11 (arom., t, 1H, ³J_HH=8); 8.13 (CH—N₃, s, 1H); 8.44 (FA, s, 1H). ESI-HRMS: 736.2217 [M]⁺ (theor. [C₂₈H₃₅N₉O₄Lu₁]⁺=736.2214).

Synthesis of 1,5-TD1413: Obtained as a side product during synthesis of 1,4-TD1413 in the form of formate salt as white fluffy solid. Yield: 4.0 mg (≤31% assuming [M]⁺[FA]⁻·xH₂O; M_R=781.6; 1 step; based on TD1408·0.1FA·2.4H₂O). NMR (D₂O, pD ˜6): ¹H δ_H 2.62-4.60 (mc, CH₂—CO, CH₂-arom., CH₂—CH₂—N₃, CH₂—CH₂—N₃, m, 16+4+3+2+1H); 4.85 (CH₂-arom., m, 1H); 5.45 (CH₂—CH₂—N₃, bs, 1H); 7.44 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.67-7.78 (arom., m, 2H); 7.81-7.90 (arom., CH—N₃, m, 1+1H); 8.02 (arom., t, 1H, ³J_HH=8); 8.25 (arom., t, 1H, ³J_HH=8); 8.45 (FA, s, 1H). ESI-HRMS: 736.2218 [M]⁺ (theor. [C₂₈H₃₅N₉O₄Lu₁]⁺=736.2214).

Synthesis of 1,5-TD1414: In a glass vial (20 mL), TD1408·0.1FA·2.4H₂O (10.0 mg; 16.4 mol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition of aq. MOPS/NaOH buffer (500 mM; pH 7.0; 820 μL; 410 μmol; 25 equiv.) and aq. YCl₃ (100 mM; 196 μL; 19.6 μmol; 1.2 equiv.). The resulting suspension was stirred 1 w at 80° C. Mixture was the filtered through syringe microfilter (RC). The filtrate was evaporated to dryness and the residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 6.6 mg (≤58% assuming [M]⁺[FA]⁻·xH₂O; M_R=695.6; 1 step; based on TD1408·0.1FA·2.4H₂O). NMR (D₂O, pD ˜6): ¹H δ_H 2.56-4.00 (mc, CH₂—CO, CH₂—CH₂—N₃, CH₂-arom., m, 16+4+2+1H); 4.06 (CH₂-arom., d, 1H, ²J_HH=15); 4.38 (CH₂-arom., d, 1H, ²J_HH=16); 4.42-4.54 (CH₂—CH₂—N₃, m, 1H); 4.93 (CH₂-arom., d, 1H, ²J_HH=15); 5.72-5.91 (CH₂—CH₂—N₃, m, 1H); 7.45 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.69-7.80 (arom., m, 2H); 7.84 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (CH—N₃, s, 1H); 8.01 (arom., t, 1H, ³J_HH=8); 8.26 (arom., t, 1H, ³J_HH=8); 8.46 (FA, s, 1H). ESI-HRMS: 650.1867 [M]⁺ (theor. [C₂₈H₃₅N₉O₄Y₁]⁺=650.1865).

Synthesis of 1,4-TD1414: Obtained as a side product during synthesis of 1,5-TD1414 in the form of formate salt as white fluffy solid. Yield: 4.0 mg (535% assuming [M]⁺[FA]⁻·xH₂O; M_R=695.6; 1 step; based on TD1408·0.1FA·2.4H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 1.76-3.19 (mc, CH₂—CO, m, 12+1H); 3.23 (CH₂—CO, d, ²J_HH=13); 3.43-3.79 (mc, CH₂—CH₂—N₃, CH₂—CO, m, 4+2+1H); 4.06-4.24 (CH₂—CH₂—N₃, CH₂-arom., m, 1+2H); 4.34 (CH₂-arom., d, 1H, ²J_HH=15); 4.60 (CH₂—CO, d, 1H, ²J_HH=12); 4.89-5.05 (CH₂—CH₂—N₃, CH₂-arom., m, 1+1H); 7.17 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.50-7.58 (arom., m, 2H); 7.72 (arom., t, 1H, ³J_HH=8); 7.74 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.09 (arom., t, 1H, ³J_HH=8); 8.14 (CH—N₃, s, 1H); 8.43 (FA, s, 1H). ESI-HRMS: 650.1868 [M]⁺ (theor. [C₂₈H₃₅N₉O₄Y₁]⁺=650.1865).

Synthesis of TD1350: In a glass vial (20 mL), TD1346·0.1FA·3.0H₂O (6.9 mg; 10.8 μmol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 550 μL; 275 μmol; 25 equiv.) and aq. LuCl₃ (100 mM; 120 μL; 12.0 μmol; 1.1 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 41.4 mg (84%; 1 step; based on TD1346-0.1FA-3.0H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.03 (CH₃, d, 3H, ³J_HH=7); 1.12 (CH₃, d, 3H, ³J_HH=7); 2.69-3.81 (mc, CH—CH₃, m, 16+2H); 3.90 (CH₂-arom., d, 1H, ²J_HH=15); 4.10 (CH₂-arom., d, 1H, ²J_HH=16); 4.23 (CH₂-arom., d, 1H, ²J_HH=15); 4.78 (CH₂-arom., d, 1H, ²J_HH=16); 5.58 (CH₂—N₃, d, 1H, ²J_HH=15); 7.11 (CH₂—N₃, d, 1H, ²J_HH=15); 7.70 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.78 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.84 (CH—N₃, s, 1H); 8.01 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.22 (arom., t, 1+1H, ³J_HH=8). ESI-HRMS: 750.2370 [M]⁺ (theor. [C₂₉H₃₇N₉O₄Lu₁]⁺=750.2371). EA ([C₂₉H₃₇N₉O₄Lu₁]⁺[TFA]⁻·0.3TFA·2.1H₂O, M_R=935.6): C 40.6 (40.6); H 4.5 (4.2); N 13.5 (13.2); F 7.9 (8.1).

Synthesis of TD1452: In a glass vial (40 mL), TD1451·0.1FA·2.7H₂O (101 mg; 112 μmol; 1.0 equiv.) was dissolved in H₂O (30 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 7.0 mL; 3.50 mmol; 31 equiv.) and aq. LuCl₃ (100 mM; 1.40 mL; 140 μmol; 1.3 equiv.) and the mixture was stirred 18 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as faint yellow fluffy solid. Yield: 115 mg (76%; 1 step; based on TD1451·0.1FA·2.7H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.12 (CH₃—CH, d, 3H, ³J_HH=7); 1.18 (CH₃—C—NH₂, s, 3H); 1.19 (CH₃—CH, d, 3H, ³J_HH=7); 1.80 (CH₃—C—NH₂, s, 3H); 2.77-3.90 (mc, CH—CO, m, 16+2H); 4.08 (CH₂-arom., d, 1H, ²J_HH=15); 4.31 (CH₂-arom., d, 1H, ²J_HH=15); 4.44 (CH₂-arom., d, 1H, ²J_HH=18); 4.87 (CH₂-arom., d, 1H, ²J_HH=18); 5.71 (CH₂—N₃, d, 1H, ²J_HH=15); 6.97 (CH₂—N₃, d, 1H, ²J_HH=15); 8.05 (arom., d, 1H, ⁴J_HH=2); 8.11 (arom., d, 1H, ⁴J_HH=1); 8.16 (arom., d, 1H, ⁴J_HH=2); 8.41 (arom., d, 1H, ⁴J_HH=1); ¹⁹F δ_F −66.1 (s). NMR (˜0.5 mM TD1452 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.12 (s). ESI-HRMS: 919.2725 [M]⁺ (theor. [C₃₄H₄₃N₁₀O₆F₃Lu₁]⁺=919.2721). EA ([C₃₃H₄₃N₁₀O₆Lu₁F₃]⁺[TFA]⁻·1.5TFA·8.3H₂O, M_R=1353.2): C 34.6 (35.4); H 4.6 (3.7); N 10.4 (9.7); F 14.7 (14.3).

Synthesis of TD1453: In a glass vial (20 mL), TD1451·0.1FA·2.7H₂O (21.7 mg; 24.1 μmol; 1.0 equiv.) was dissolved in H₂O (18 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 1.50 mL; 750 μmol; 31 equiv.) and aq. ErCl₃ (100 mM; 300 μL; 30.0 μmol; 1.2 equiv.) and the mixture was stirred 10 d at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 22.6 mg (˜70% assuming [M]⁺[TFA]⁻·1.5TFA·8.3H₂O; M_R=1345; 1 step; based on TD1451·0.1FA·2.7H₂O). NMR (˜0.5 mM TD1453 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −47.85 (s). ESI-HRMS: 910.2620 [M]⁺ (theor. [C₃₄H₄₃N₁₀O₆F₃Er₁]⁺=910.2617).

Synthesis of TD1472: In a glass vial (4 mL), [TD1452]⁺[TFA]⁻·1.5TFA·8.3H₂O (20.0 mg; 14.8 μmol; 1.0 equiv.) was dissolved in DMSO (1.5 mL) followed by addition of AcOH (42 μL; 735 μmol; 50 equiv.) and DIPEA (181 μL; 1.04 mmol; 70 equiv.). Freshly prepared solution of PyAOP (200 mM in DMSO; 368 μL; 73.7 μmol; 5.0 equiv.) was then added and the resulting mixture was stirred 5 min at RT. The resulting biphasic mixture was diluted with DMF (800 μL), and the resulting solution was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 11.5 mg (64%; 1 step; based on [TD1452]⁺[TFA]⁻·1.5TFA·8.3H₂O). NMR (˜0.5 mM TD1472 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.10 (s). EA ([C₃₆H₄₅N₁₀O₇Lu₁F₃]⁺[TFA]⁻·0.8TFA·3.1H₂O, M_R=1221.8): C 38.9 (39.1); H 4.3 (4.5); N 11.5 (11.3).

Synthesis of TD1473: In a glass vial (4 mL), [TD1452]⁺[TFA]⁻·1.5TFA·8.3H₂O (16.2 mg; 12.0 μmol; 1.0 equiv.) was dissolved in a MeOH (1.20 mL) followed by addition of SOCl₂ (8.8 μL; 121 μmol; 10 equiv.). The resulting clear solution was stirred 2 d at 50° C. Mixture was then diluted with H₂O (2 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 13.2 mg (91%; 1 step; based on [TD1452]⁺[TFA]⁻·1.5TFA·8.3H₂O). NMR (˜0.5 mM TD1473 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.13 (s). EA ([C₃₅H₄₅N₁₀O₆Lu₁F₃]⁺[TFA]⁻·0.2TFA·7.2H₂O, M_R=1199.2): C 37.5 (37.1); H 5.0 (4.0); N 11.7 (10.7).

Synthesis of TD1475: In a glass vial (4 mL), TD1453 (assuming [TD1453]⁺[TFA]⁻·1.5TFA·8.3H₂O; M_R=1345; 20.6 mg; 15.3 μmol; 1.0 equiv.) was dissolved in a MeOH (1.50 mL) followed by addition of SOCl₂ (11.2 μL; 154 μmol; 10 equiv.). The resulting clear solution was stirred 2 d at 50° C. Mixture was then diluted with H₂O (2 mL) and directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 15.5 mg (˜85% assuming [M]⁺[TFA]⁻·0.2TFA·7.2H₂O; M_R=1192; 1 step; based on [TD1453]). NMR (˜0.5 mM TD1475 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −48.45 (s).

Synthesis of TD1506: In a glass vial (20 mL), TD1504 (assuming M·2.0H₂O; M_R=657.7, 8.7 mg; 13.2 μmol; 1.0 equiv.) was dissolved in H₂O (19 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 595 μL; 398 μmol; 30 equiv.) and aq. LuCl₃ (100 mM; 159 μL; 15.9 μmol; 1.2 equiv.) and the mixture was stirred 16 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with products (both diastereoisomers were fully separated) were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 6.9+3.4 mg (≤62+31% assuming [M]⁺[FA]⁻·xH₂O; M_R=836.6; 1 step; based on TD1504·2.0H₂O). NMR (first isomer, D₂O, pD ˜4): ¹H δ_H 1.06 (CH₃, d, 3H, ³J_HH=7); 2.53-2.65 (CH₂—CO, m, 2H); 2.76-3.84 (mc, CH—CH₂, CH—CH₃, m, 16+1+1H); 3.96 (CH₂-arom., d, 1H, ²J_HH=15); 4.13 (CH₂-arom., d, 1H, ²J_HH=16); 4.27 (CH₂-arom., d, 1H, ²J_HH=15); 4.77 (CH₂-arom., d, 1H, ²J_HH=16); 5.61 (CH₂—N₃, d, 1H, ²J_HH=15); 7.11 (CH₂—N₃, d, 1H, ²J_HH=15); 7.78 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.81 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.85 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.87 (CH—N₃, s, 1H); 8.03 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.25 (arom., t, 1H, ³J_HH=8); 8.28 (arom., t, 1H, ³J_HH=8); 8.40 (FA, s, 1H). NMR (second isomer, D₂O, pD ˜5): ¹H δ_H 1.14 (CH₃, d, 3H, ³J_HH=7); 2.38-2.61 (CH₂—CO, m, 2H); 2.76-3.82 (mc, CH—CH₂, CH—CH₃, m, 16+1+1H); 3.92 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.25 (CH₂-arom., d, 1H, ²J_HH=15); 4.80 (CH₂-arom., d, 1H, ²J_HH=16); 5.61 (CH₂—N₃, d, 1H, ²J_HH=15); 7.14 (CH₂—N₃, d, 1H, ²J_HH=15); 7.73 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.90 (CH—N₃, s, 1H); 8.03 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 8.24 (arom., t, 1H, ³J_HH=8); 8.27 (arom., t, 1H, ³J_HH=8); 8.45 (FA, s, 1H). ESI-MS (LC-MS): 794.2 [M]⁺ (theor. [C₃₀H₃₇N₉O₆Lu₁]⁺=794.2).

Synthesis of TD1512: In a glass vial (2 mL), [TD782]⁺[TFA]⁻·5.1H₂O (0.5 mg; 0.52 μmol; 1.0 equiv.) was dissolved in solution of freshly prepared DIPEA (100 mM in DMSO; 104 μL; 10.4 μmol; 20 equiv.) followed by addition of freshly prepared solution of NaSH (500 mM in DMSO; 4.2 μL; 2.1 μmol; 4 equiv.) and the resulting mixture was stirred 15 min at RT. Mixture was diluted with H₂O (800 μL) and purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 0.2 mg (≤44% assuming [M]⁺[TFA]⁻·xH₂O; M_R=867.6; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜4): ¹H δ_H 2.63-3.79 (mc, CH₂—CO, CH₂-arom., m, 16+4+1H); 4.05-4.17 (CH₂-arom., m, 2H); 4.79 (CH₂-arom., d, 1H, ²J_HH=15); 5.28 (CH₂—N₃, d, 1H, ²J_HH=15); 6.83 (CH₂—N₃, d, 1H, ²J_HH=15); 7.47 (arom., d, 1H, ⁴J_HH=2); 7.72 (arom., d, 1H, ⁴J_HH=2); 7.79 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.83 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH—N₃, s, 1H); 8.23 (arom., t, 1H, ³J_HH=8). ESI-MS (LC-MS): 754.2 [M]⁺ (theor. [C₂₇H₃₃N₉O₄S₁Lu₁]⁺=754.2).

Synthesis of TD1512-SO₃H: In a glass vial (2 mL), [TD782]⁺[TFA]⁻·5.1H₂O (1.0 mg; 1.0 μmol; 1.0 equiv.) was dissolved in H₂O (156 μL) followed by addition of aq. solution of Na₂S (100 mM; 52 μL; 5.2 μmol; 5 equiv.) and the resulting mixture was stirred at 80° C. overnight. Mixture was diluted with H₂O (800 μL) and purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 0.3 mg (≤32% assuming [M]⁺[TFA]⁻·xH₂O; M_R=915.6; 1 step; based on [TD782]⁺[TFA]⁻·5.1H₂O). NMR (D₂O, pD ˜7): ¹H δ_H 2.60-3.83 (mc, CH₂—CO, CH₂-arom., m, 16+4H); 4.09 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.35 (CH₂-arom., d, 1H, ²J_HH=15); 4.82 (CH₂-arom., d, 1H, ²J_HH=16); 5.72 (CH₂—N₃, d, 1H, ²J_HH=15); 7.16 (CH₂—N₃, d, 1H, ²J_HH=15); 7.82 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.86 (arom., dd, 1H, ³J_HH=8, ⁴J_HH=1); 7.88 (CH—N₃, s, 1H); 8.06 (arom., d, 1H, ⁴J_HH=2); 8.25 arom., t, 1H, ³J_HH=8); 8.36 (arom., d, 1H, ⁴J_HH=2). ESI-MS (LC-MS): 802.1 [M]⁺ (theor. [C₂₇H₃₃N₉O₇S₁Lu₁]⁺=802.2).

Example 7: Synthesis of Chains of Coordination Compounds

Synthesis of TD837: In a glass vial (4 mL), aq. solution of [TD836]⁺[TFA]⁻·xH₂O (˜20 mM; 274 μL; ˜5.5 μmol; 1.0 equiv.) was mixed with aq. solution of [TD823]⁺[TFA]⁻·xH₂O (˜20 mM; 274 μL; ˜5.5 μmol; 1.0 equiv.) followed by addition of aq. MES/NaOH buffer (500 mM; pH 5.2; 548 μL; 274 μmol; ˜50 equiv.), t-BuOH (1.1 mL) and aq. solution of CuSO₄ (100 mM; 11 μL; 1.1 μmol; ˜0.2 equiv.). To the resulting solution was added freshly prepared aq. solution of sodium ascorbate (100 mM; 11 μL; 1.1 μmol; ˜0.2 equiv.) and the mixture was stirred 2 h at RT. The mixture was then concentrated to ˜1 mL and then purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 4.7 mg (≤50% assuming [M]²⁺[TFA]₂²⁻·xH₂O; M_R=1721; 1 step; based on [TD836]⁺[TFA]⁻·xH₂O). ESI-HRMS: 747.1998 [M]²⁺ (theor. [C₅₆H₆₅N₂₁O₈Tb₁¹⁷⁶Yb₁]2+=747.1997).

Synthesis of TD889: In a glass vial (4 mL), aq. solution of [TD836]⁺[TFA]⁻·xH₂O (˜20 mM; 274 μL; ˜5.5 μmol; 1.0 equiv.) was mixed with aq. solution of [TD886]⁺[TFA]⁻·xH₂O (˜20 mM; 274 μL; ˜5.5 μmol; 1.0 equiv.) followed by addition of aq. MES/NaOH buffer (500 mM; pH 5.2; 548 μL; 274 μmol; ˜50 equiv.), t-BuOH (1.1 mL) and aq. solution of CuSO₄ (100 mM; 28 μL; 2.8 μmol; ˜0.5 equiv.). To the resulting solution was added freshly prepared aq. solution of sodium ascorbate (100 mM; 28 μL; 2.8 μmol; ˜0.5 equiv.) and the mixture was stirred 30 min at RT. The mixture was then concentrated to ˜1 mL and then purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 7.8 mg (≤82% assuming [M]²⁺[TFA]₂²⁻·xH₂O; M_R=1721; 1 step; based on [TD836]⁺[TFA]⁻·xH₂O). ESI-HRMS: 747.2002 [M]²⁺ (theor. [C₅₆H₆₅N₂₁O₈Tb₁¹⁷⁶Yb₁]²⁺=747.1997)

Synthesis in TD1483: In a glass vial (4 mL), [TD1472]⁺[TFA]⁻·0.8TFA·3.1H₂O (7.8 mg; 6.4 μmol; 1.0 equiv.) and [TD1473]⁺[TFA]⁻·0.2TFA·7.2H₂O (7.5 mg; 6.4 mol; 1.0 equiv.) were dissolved in DMSO (335 μL) followed by addition of DIPEA (400 mm in DMF; 240 μL; 96 μmol; 15 equiv.). Freshly prepared solution of PyAOP (200 mM in DMSO; 64 μL; 12.8 μmol; 2.0 equiv.) was then added and the resulting mixture was vortexed for 1 min and further left standing for 5 min at RT. Mixture was then diluted with H₂O (1 mL), vortexed for 1 min and further left standing for 5 min at RT. Reaction mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid. Yield: 10.8 mg (≤80% assuming [M]²⁺[TFA]₂⁻·xH₂O; M_R=2090; 1 step; based on [TD1472]⁺[TFA]⁻·0.8TFA·3.1H₂O). NMR (˜0.5 mM TD1483 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −66.10 (CF₃, s, 3F); ˜66.11 (CF₃, s, 3F).

Synthesis of TD1484: In a glass vial (4 mL), TD1483 (˜20 mM in DMSO; 20 μL; 0.4 μmol; 1.0 equiv.), TD1473 (˜20 mM in DMSO; 20 μL; 0.4 μmol; 1.0 equiv.), DIPEA (400 mM in DMF; 15 μL; 6.0 μmol; 15 equiv.) and DMSO (21 μL) were mixed together followed by addition of PyAOP (200 mm in DMSO; 4 μL; 0.8 μmol; 2.0 equiv.) and the resulting mixture was stirred 30 min at RT. Mixture was then diluted with H₂O (2 mL) and further stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized. All of the obtained product was used for ¹⁹F NMR characterization. NMR (˜0.5 mM TD1484 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −65.86 (CF₃, s, 3F); ˜66.09 (CF₃, s, 3F); ˜66.10 (CF₃, s, 3F).

Synthesis of TD1512-SS: Obtained as a side product (in the form of trifluoroacetate salt) during synthesis and purification of TD1512. Yield: 0.1 mg. ESI-MS (LC-MS): 753.3 [M]2+(theor. [C₅₄H₆₄Lu₂N₁₈O₈S₂]²⁺=753.2).

Synthesis: In a glass vial (4 mL), TD1483 (˜20 mM in DMSO; 20 μL; 0.4 μmol; 1.0 equiv.) TD1475 (˜20 mM in DMSO; 20 μL; 0.4 μmol; 1.0 equiv.), DIPEA (400 mM in DMF; 15 μL; 6.0 μmol; 15 equiv.) and DMSO (21 μL) were mixed together followed by addition of PyAOP (200 mM in DMSO; 4 μL; 0.8 μmol; 2.0 equiv.) and the resulting mixture was stirred 30 min at RT. Mixture was then diluted with H₂O (2 mL) and further stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized. All of the obtained product was used for ¹⁹F NMR characterization. NMR (˜0.5 mM TD1485 in ˜50 mM MOPS/NaOH buffer in 10% D₂O, pH 7.0): ¹⁹F δ_F −48.05 (CF₃, s, 3F); ˜65.13 (CF₃, s, 3F); ˜67.24 (CF₃, s, 3F).

Example 8: Synthesis of Dimers of Coordination Compounds

Synthesis of sc-TD647: Obtained as side product during synthesis of TD647. Yield: −8 mg. NMR (D₂O): ¹H δ_H 2.69-3.65 (mc and CH₂—CO, 32+8H); 3.68 (C≡CH, s, 1H); 3.70 (CH₂-arom., bs, 2H); 3.75-4.12 (CH₂-arom., 6H); 4.59 (CH₂—N₃., s, 2H); 5.89 (CH₂—N₃, s, 2H); 7.36-7.97 (Ph and arom., 10+8H); 8.15 (arom., bs, 1H); 8.32 (arom., bs, 1H); 8.64 (CH—N₃, s, 1H). ESI-HRMS: 1251.6313 [M+H]⁺ (theor. [C₆₆H₇₉N₁₈O₈]⁺=1251.6323).

Synthesis of TD613: In a glass vial (20 mL), sc-TD647·xH₂O (5.0 mg; ˜4 μmol; 1.0 equiv.) was dissolved in H₂O (14 mL) followed by addition aq. MOPS/NaOH buffer (500 mM; pH 7.0; 800 μL; 400 mmol; ˜100 equiv.) and aq. LuCl₃ (100 mM; 88 μL; 8.8 μmol; ˜2.2 equiv.) and the mixture was stirred 1 h at 80° C. Mixture was then filtered through syringe microfilter (RC). The filtrate was concentrated on rotary evaporator and then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with FA additive). Fractions with product were joined and directly lyophilized to give product in the form of formate salt as white fluffy solid. Yield: 4 mg (˜60%; 1 step; based on sc-TD647·xH₂O). ESI-HRMS: 798.2368 [M]²⁺ (theor. [C₆₆H₇₄N₁₈O₈Lu₂^]2+=798.2371).

Synthesis of TD598: Obtained as side product during synthesis of TD651 in the form of formate salt as white fluffy solid. Yield: 6 mg. NMR (D₂O, pD ˜5): ¹H δ_H 2.47-3.99 (mc, CH₂—CO, CH₂-arom, m, 32+8+4H); 4.42

(CH₂-arom., d, 2H, ²J_HH=17); 4.75 (CH₂-arom., d, 2H, 2J_HH=17); 5.90 (CH₂—N₃, d, 2H, 2J_HH=16); 6.20 (CH₂—N₃, d, 2H, ²J_HH=16); 7.07 (arom., d, 2H, ⁴J_HH=2); 7.44 (arom., d, 2H, ⁴J_HH=2); 7.47-7.63 (Ph, m, 10H); 7.66 (arom., dd, 2H, ³J_HH=8, ⁴J_HH=1); 7.89 (arom., dd, 2H, ³J_HH=8 ⁴J_HH=1); 8.15 (arom., t, 2H, ³J_HH=8); 8.42 (FA, s); 8.74 (CH N₃, s, 2H). ¹³C{¹H} δ_C 49.3 (mc, s); 49.4 (mc, s); 51.0 (mc, s); 51.6 (mc, s); 52.5 (mc, s); 53.9 (mc, s); 54.0 (mc, s); 54.3 (mc, s); 55.6 (CH₂—N₃, s); 59.2 (CH₂-arom., s); 59.8 (CH₂—CO, s); 61.2 (CH₂-arom., s); 61.9 (CH₂—CO, s); 120.7 (arom., s); 121.2 (arom., s); 122.2 (arom., s); 125.4 (arom., s); 126.7 (CH—N₃, s); 128.2 (Ph, s); 129.6 (Ph, s); 131.6 (Ph, s); 135.2 (Ph, s); 143.0 (arom., s); 145.5 (arom., s); 148.9 (arom., s); 150.2 (arom., s); 157.2 (arom., s); 157.3 (arom., s); 158.9 (arom., s); 170.8 (FA, s); 177.9 (CO, s); 180.5 (CO, s). ESI-HRMS: 762.2025 [M]²⁺ (theor. [C₆₆H₇₄N₁₈O₈La₂^]2+=762.2027).

Example 9: Synthesis of Conjugates of Coordination Compounds with Peptides

Synthesis of TD981: In a glass vial #1(20 mL), HO—R(N_ω—NO₂)-Fmoc (886 mg; 2.01 mmol; 1.1 equiv.) was dissolved (with the help of vortexing/gentle heating) in DMSO (6 mL) followed by addition of DBU (550 μL; 3.68 mmol; 2.0 equiv.) and the resulting solution was briefly vortexed and further stirred 2 mins at RT. In a glass vial #2 (20 mL), HO-DR(Pbf-Fmoc (1.20 g; 1.85 mmol; 1.0 equiv. was dissolved (with the help of vortexing/gentle heating) in a mixture of DMSO (9 mL) and NMM (1.0 mL; 9.09 mmol; 4.9 equiv.) followed by addition of solid PyAOP (965 mg; 1.85 mmol; 1.0 equiv.). The mixture was briefly vortexed and the resulting slightly yellow solution was further stirred 2 mins at RT). Solution from vial #1 was then added in one portion (via syringe) to the intensively stirred solution in vial #2. Resulting bright yellow solution was further gentle stirred 5 mins at RT after which neat TFA (430 μL; 5.62 mmol; 3.0 equiv.) was added. Mixture was then directly purified by flash chromatography (C18; H₂O-MeCN gradient with TFA additive). Fractions with pure product were joined and directly lyophilized. Fractions containing impure product were joined, lyophilized and subsequently re-purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive) and re-lyophilized. Both solids were then joined and homogenized to give product as off-white solid. Yield: 1.21 g (63%; 2 steps; based on HO-^DR(Pbf)-H). ESI-MS (LC-MS): 850.4 [M+H]⁺ (theor. [C₄₀H₅₂N₉O₁₀S₁]⁺=850.3). EA (C₄₀H₅₁N₉O₁₀S₁·1.4TFA·1.4H₂O, M_R=1034.8): C 49.7 (50.0); H 5.4 (5.1); N 12.2 (11.8); F 7.7 (7.8).

Synthesis of TD982: In a glass vial (20 mL), TD981·1.4TFA·1.4H₂O (360 mg; 348 μmol; 1.1 equiv.) and NH₄Cl (27 mg; 505 μmol; 1.5 equiv.) were dissolved (with the help of vortexing/gentle heating) in DMSO (2 mL) followed by addition of NMM (140 μL; 1.27 mmol; 3.0 equiv.) and of solid PyAOP (264 mg; 506 μmol; 1.5 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 5 mins at RT followed by addition of DBU (380 μL; 2.54 mmol; 7.3 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 2 mins at RT after which neat TFA (160 μL; 2.09 mmol; 6.0 equiv.) was added. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with pure product were joined and directly lyophilized to give product as white fluffy solid. Yield: 237 mg (74%; 2 steps; based on TD981·1.4TFA·1.4H₂O). ESI-MS (LC-MS): 627.4 [M+H]⁺ (theor. [C₂₅H₄₂N₁₀O₇S₁]⁺=627.3). EA (C₂₅H₄₂N₁₀O₇S₁·2.3TFA·1.9H₂O, M_R=923.2): C 38.5 (38.7); H 5.3 (4.9); N 15.2 (14.8); F 14.2 (14.0).

Synthesis of TD986: In a glass vial (20 mL), TD981·1.4TFA·1.4H₂O (258 mg; 249 μmol; 1.0 equiv.) and TD982·2.3TFA·1.9H₂O (222 mg; 240 μmol; 1.0 equiv.) were dissolved (with the help of vortexing/gentle heating) in DMSO (2 mL) followed by addition of NMM 220 μL; 2.00 mmol; 8.3 equiv.) and of solid PyAOP (136 mg; 261 μmol; 1.1 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 15 mins at RT followed by addition of DBU (221 μL; 1.48 mmol; 6.2 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 15 mins at RT after which another portion of DBU (36 μL; 241 μmol; 1.0 equiv.) was added. Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 5 mins at RT after which neat TFA (58 μL; 758 μmol; 3.2 equiv.) was added. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with pure product were joined and directly lyophilized. The resulting tetraarginine intermediate NH₂—R(N_ω—NO₂)^DR(Pbf)R(N_ω—NO₂)^DR(Pbf)-H (≤238 μmol; 1.0 equiv.) was transferred to a glass vial (20 mL) followed by addition of TD981·1.4TFA·1.4H₂O (259 mg; 250 μmol; ≥1.1 equiv.), DMSO (2 mL; dissolved with the help of vortexing/gentle heating), NMM (276 μL; 2.51 mmol; ≥10.5 equiv.) and of solid PyAOP (144 mg; 277 μmol; ≥1.2 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 20 mins at RT followed by addition of DBU (263 μL; 1.76 mmol; ≥7.0 equiv.). Mixture was briefly vortexed and the resulting bright yellow solution was further stirred 5 mins at RT after which neat TFA (77 μL; 1.00 mmol; ≥4.0 equiv.) was added. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with pure product were joined and directly lyophilized to give product as white fluffy solid. Yield: 368 mg (66%; 4 steps; based on TD982·2.3TFA·1.9H₂O). ESI-MS (LC-MS): 923.6 [M+2H]²⁺ (theor. [C₇₅H₁₂₀N₂₈O₂₁S₃^]2+=923.4). EA (C₇₅H₁₂₀N₂₈O₂₁S₃·3.2TFA·5.3H₂O, M_R=2306.4): C 42.4 (42.8); H 5.8 (5.4); N 17.0 (16.6); F 7.9 (7.6).

Synthesis of TD802: In a glass vial (4 mL), [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O (3.3 mg; 2.8 μmol; 1.0 equiv.) and H₂N-GVHFYA-H·1.0TFA·xH₂O (3.4 mg; ˜4.2 μmol; ˜1.5 equiv.) were dissolved in DMSO (1 mL) followed by addition of DIPEA (5.0 μL; 29 μmol; ˜10 equiv.) and PyOAP (freshly prepared 100 mm in DMSO; 52 μL; 5.2 μmol; 1.9 equiv.) and the resulting yellow solution was stirred 20 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 4.4 mg (≤96% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1629.5; 1 step; based on [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 0.93 (^VCH₃, d, 3H, ³J_HH=7); 0.95 (^VCH₃, d, 3H, ³J_HH=7); 1.42 (^ACH₃, d, 3H, ³J_HH=7); 2.03 (^VCH—(CH₃)₂, dhept, 1H, ³J_HH=7, ³J_HH=7); 2.62-3.81 (mc, CH₂—CO, ^HCH₂, ^FCH₂, CH₂, m, 16+4+2+2+2H); 3.84 (^GCH₂, d, 1H, ²J_HH=17); 3.95 (^GCH₂, d, 1H, ²J_HH=17); 4.01 (CH₂-arom., d, 1H, ²J_HH=15); 4.02 (^VCH, d, 1H, ³J_HH=7); 4.15 (CH₂-arom., d, 1H, ²J_HH=16); 4.35 (CH₂-arom., d, 1H, ²J_HH=15); 4.45 (^ACH, q, 1H, ³J_HH=7); 4.52-4.66 (^HCH, ^FCH, ^YCH, m, 1+1+1H); 4.85 (CH₂-arom., d, 1H, ²J_HH=16); 5.67 (CH₂—N₃, d, 1H, ²J_HH=15); 6.59 (^Yarom., dm, 2H, ³J_HH=8); 6.96 (^Yarom., dm, 2H, ³J_HH=8); 7.08-7.18 (CH₂—N₃, ^Farom., m, 1+2H); 7.19 (^Harom., s, 1H); 7.23-7.30 (^Farom. m, 3H); 7.81 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.82-7.87 (arom., m, 3H); 7.89 (CH N₃, s, 1H); 8.00 (arom., dm, 2H, ³J_HH=8); 8.03 (arom., d, 1H, ⁴J_HH=2); 8.24 (arom., t, 1H, ³J_HH=8); 8.33 (arom., d, 1H, ⁴J_HH=2); 8.48 (^Harom., bs, 1H). ESI-HRMS: 1515.5593 [M](theor. [C₆₈H₈₀N₁₈O₁₂Lu₁]⁺=1515.5605).

Synthesis of TD792: In a glass vial (4 mL), [TD785]⁺[TFA]⁻·0.6TFA·4.8H₂O (3.0 mg; 2.9 μmol; 1.0 equiv.) and H₂N-GVHFYA-H 1.0TFA·xH₂O peptide (3.4 mg; ˜4.2 μmol; ˜1.4 equiv.) were dissolved in DMSO (1 mL) followed by addition of DIPEA (5.0 μL; 29 μmol; ˜10 equiv.) and PyOAP (freshly prepared 100 mM in DMSO; 52 μL; 5.2 μmol; 1.8 equiv.) and the resulting yellow solution was stirred 20 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 4.0 mg (≤89% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1543.3; 1 step; based on [TD785]⁺[TFA]0.6TFA·4.8H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 0.93 (^VCH₃, d, 3H, ³J_HH=7); 0.95 (^VCH₃, d, 3H, ³J_HH=7); 1.42 (^ACH₃, d, 3H, ³J_HH=7); 2.03 (^VCH—(CH₃)₂, dhept, 1H, ³J_HH=7, ³J_HH=7); 2.62-3.81 (mc, CH₂—CO, ^HCH₂, ^FCH₂, CH₂, m, 16+4+2+2+2H); 3.84 (^GCH₂, d, 1H, ²J_HH=17); 3.95 (^GCH₂, d, 1H, ²J_HH=17); 4.01 (CH₂-arom., d, 1H, ²J_HH=15); 4.02 (^VCH, d, 1H, ³J_HH=7); 4.14 (CH₂-arom., d, 1H, ²J_HH=16); 4.39 (CH₂-arom., 20 d, 1H, ²J_HH=15); 4.45 (^ACH, q, 1H, ³J_HH=7); 4.52-4.67 (^HCH, ^FCH, ^YCH, m, 1+1+1H); 4.85 (CH₂- arom., d, 1H, ²J_HH=16); 5.72 (CH₂—N₃, d, 1H, ²J_HH=16); 6.59 (^Yarom., dm, 2H, ³J_HH=8); 6.96 (^Yarom., dm, 2H, ³J_HH=8); 7.09 (CH₂—N₃, d, 1H, ²J_HH=16); 7.10-7.16 (^Farom., m, 2H); 7.21 (^Harom., s, 1H); 7.24-7.30 (^Farom m, 3H); 7.78-7.86 (arom., m, 4H); 7.89 (CH N₃, s, 1H); 8.00 (arom., dm, 2H, ³J_HH=8); 8.03 (arom., d, 1H, ⁴J_HH=2); 8.25 (arom., t, 1H, ³J_HH=8); 8.33 (arom., d, 1H, ⁴J_HH=2); 8.53 (^Harom., t, 1H, ⁴J_HH=2). ESI-HRMS: 1429.5264 [M](theor. [C₆₈H₈₀N₁₈O₁₂Y₁]⁺=1429.5256).

Synthesis of TD901: In a glass vial (4 mL), [TD899]⁺[TFA]⁻·0.2TFA·7.0H₂O (1.6 mg; 1.4 μmol; 1.0 equiv.) and H₂N-GVHFYA-H 1.0TFA·xH₂O (1.6 mg; ˜2.0 μmol; ˜1.4 equiv.) were dissolved in DMSO (500 μL) followed by addition of DIPEA (2.3 μL; 13 μmol; 9 equiv.) and PyOAP (freshly prepared 100 mm in DMSO; 25 μL; 2.5 μmol; 1.7 equiv.) and the resulting yellow solution was stirred 40 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 2.0 mg (≤85% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1637.5; 1 step; based on [TD899]⁺[TFA]⁻·0.2TFA·7.0H₂O). ESI-HRMS: 762.2885 [M+H]²⁺ (theor. [C₆₉H₈₃N₁₈O₁₂Tm₁]²⁺=762.2887).

Synthesis of TD902: In a glass vial (4 mL), [TD891]⁺[TFA]⁻·0.7TFA·4.6H₂O (1.6 mg; 1.4 μmol; 1.0 equiv.) and H₂N-GVHFYA-H 1.0TFA·xH₂O (1.6 mg; ˜2.0 mol; ˜1.4 equiv.) were dissolved in DMSO (500 μL) followed by addition of DIPEA (2.3 μL; 13 μmol; 9.4 equiv.) and PyOAP (freshly prepared 100 mM in DMSO; 25 μL; 2.5 μmol; 1.8 equiv.) and the resulting yellow solution was stirred 40 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product as white fluffy solid. Yield: 1.8 mg (≤78% assuming [M]⁺[TFA]⁻·xH₂O; M_R=1643.5; 1 step; based on [TD891]⁺[TFA]⁻·0.7TFA·4.6H₂O). NMR (D₂O, pD ˜4, assignment was complicated by two distinguishable diastereomeric set of most of the signals): ¹H δ_H 0.91 (^VCH₃, d, 3H, ³J_HH=7); 0.93 (^VCH₃, d, 3H, ³J_HH=7); 1.36 (^ACH₃, d, 3H, ³J_HH=7); 1.90-4.21 (^VCH—(CH₃)₂, mc, CH₂—CO, ^HCH₂, ^FCH₂, ^YCH₂, ^GCH₂, CH₂-arom., ^VCH, ACH, m, 1+16+4+2+2+2+2+5+1+1H); 4.21-4.56 (^HCH, ^FCH, ^YCH, m, 1+1+1H); 4.81-4.90 (CH₂-arom., m, 1H); 5.52-5.62 (CH₂—N₃, m, 1H); 6.77-7.18 (^Yarom., CH₂—N₃, ^Farom., ^Harom., ^Farom., m, 4+1+2+1+3H); 7.34-8.10 (arom., CH—N₃, 8+1H); 8.21-8.30 (arom., m, 1H); 8.52-8.58 (^Harom., m, 1H). ESI-HRMS: 765.2919 [M+H]²⁺ (theor. [C₆₉H₈₃N₁₈O₁₂Lu₁]²⁺=765.2917).

Synthesis of TD975: In a glass vial (4 mL), [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O (7.1 mg; 6.1 μmol; 1.0 equiv.) and H₂N— −[^LR(Pbf)^DR(Pbf)]₃-H·1.0TFA·xH₂O (21 mg; ˜8.1 μmol; ˜1.3 equiv.) were dissolved in DMSO (1 mL) followed by addition of NMM (20 μL; 182 μmol; 30 equiv.) and PyOAP (15.5 mg; 29.7 μmol; 5.0 equiv.) and the resulting yellow solution was stirred 20 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with Pbf protected product were joined, evaporated to dryness and twice co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and the residue was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid (the amount of TFA was determined by qNMR using external capillary solution of 1,3,5-tris(trifluoromethyl)benzene in CCl₄). Yield: 13.0 mg (˜85% assuming [M]⁺[TFA]⁻·5.4TFA·xH₂O; M_R=2510; 2 steps; based on [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O). NMR (D₂O, pD ˜3): ¹H δ_H 1.41-2.07 (^RCH₂, m, 24H); 2.63-3.88 (mc, CH₂—CO, ^RCH₂, m, 16+4+12H); 4.05 (CH₂-arom., d, 1H, ²J_HH=15); 4.18 (CH₂-arom., d, 1H, ²J_HH=16); 4.21-4.57 (^RCH, CH₂-arom., m, 5+1H); 4.53 (^RCH, t, 1H, ³J_HH=7); 4.87 (CH₂-arom., d, 1H, ²J_HH=16); 5.69 (CH₂—N₃, d, 1H, ²J_HH=15); 7.19 (CH₂—N₃, d, 1H, ²J_HH=15); 7.82 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.88 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.91 (CH—N₃, s, 1H); 8.03 (arom., dm, 2H, ³J_HH=8); 8.06-8.12 (arom., m, 3H); 8.27 (arom., t, 1H, ³J_HH=8); 8.39 (arom., d, 1H, ⁴J_HH=2). MALDI-HRMS: 1777.8487 [M]⁺ (theor. [C₇₀H₁₁₀N₃₄O₁₁Lu₁]⁺=1777.8496).

Synthesis of TD989: In a glass vial (4 mL), [TD897]⁺[TFA]⁻·1.1TFA·2.6H₂O (15.0 mg; 13.4 μmol; 1.0 equiv.) and TD986·3.2TFA·5.3H₂O (30.9 mg; 13.4 μmol; 1.0 equiv.) were dissolved in DMSO (1.5 mL) followed by addition of solution of NMM (400 mM, 335 μL; 134 μmol; ˜10 equiv.) in DMSO and freshly prepared solution of PyOAP (110 mM; 210 μL; 23.1 μmol; 1.7 equiv.) in DMSO and the resulting yellow solution was stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with fully protected product were joined, evaporated to dryness and twice co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and stirred overnight at RT to remove Pbf groups. Resulting blue solution was evaporated to dryness and the residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with partly protected product were joined, and evaporated to dryness. Residue was re dissolved in H₂O (10 mL) and transferred via syringe through septum to a glass flask (25 mL) already filled with Pd/C (30 mg) and argon secured. Hydrogen gas was then left bubbling through the suspension for 2 days at RT. Mixture was then filtered through syringe microfilter (RC), and the filtrate was evaporated to dryness. Residue was purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid (the amount of TFA was set arbitrary from analogous TD975). Yield: 14.6 mg (˜45% assuming [M]⁺[TFA]⁻·5.4TFA·xH₂O; M_R=2505; 3 steps; based on [TD897]⁺[TFA]⁻·1.1TFA·2.6H₂O). MALDI-HRMS: 1771.8412 [M]⁺ (theor. [C₇₀H₈₃N₃₄O₁₁Tm₁]⁺=1771.8435).

Synthesis of TD1011: In a glass vial (4 mL), [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O (15.0 mg; 12.8 μmol; 1.0 equiv.) and TD986·3.2TFA·5.3H₂O (31 mg; 13.4 μmol; 1.0 equiv.) were dissolved in DMSO (1.5 mL) followed by addition of solution of NMM (400 mM, 340 μL; 136 μmol; 11 equiv.) in DMSO and freshly prepared solution of PyOAP (110 mM; 210 μL; 23.1 μmol; 1.8 equiv.) in DMSO and the resulting yellow solution was stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with Pbf protected product were joined, evaporated to dryness and twice co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and the residue was suspended in 20% MeCN (3 mL). Mixture was filtered through syringe microfilter (RC) and the filtrate was directly purified by preparative HPLC (C18; H₂O—MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid (the amount of TFA was determined by qNMR using external capillary solution of 1,3,5-tris(trifluoromethyl)benzene in CCl₄). Yield: 18.4 mg (˜55% assuming [M]⁺[TFA]⁻·4.5TFA·xH₂O; M_R=2540; 2 steps; based on [TD748]⁺[TFA]⁻·1.4TFA·3.2H₂O). NMR (D₂O, pD ˜5): ¹H δ_H 1.39-2.07 (^RCH₂, m, 24H); 2.63-3.85 (mc, CH₂—CO, ^RCH₂, m, 16+4+12H); 4.04 (CH₂-arom., d, 1H, ²J_HH=15); 4.16 (CH₂-arom., d, 1H, ²J_HH=16); 4.21-4.66 (^RCH, CH₂-arom., m, 6+1H); 4.86 (CH₂-arom., d, 1H, ²J_HH=16); 5.69 (CH₂—N₃, d, 1H, ²J_HH=15); 7.18 (CH₂—N₃, d, 1H, ²J_HH=15); 7.81 (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.86j (arom., dd, 1H, ³J_HH=8; ⁴J_HH=1); 7.90 (CH N₃, s, 1H); 7.95-8.09 (arom., m, 5H); 8.25 (arom., t, 1H, ³J_HH=8); 8.37 (arom., d, 1H, ⁴J_HH=2). MALDI-HRMS: 1912.8054 [M]⁺ (theor. [C₇₀H₁₀₇N₃₇O₁₇Lu₁]⁺=1912.8048).

Synthesis of TD1010: In a glass vial (4 mL),), [TD897]1[TFA]⁻·1.1TFA·2.6H₂O (10.0 mg; 8.9 μmol; 1.0 equiv.) and TD986·3.2TFA·5.3H₂O (21 mg; 9.1 μmol; 1.0 equiv.) were dissolved in DMSO (1.0 mL) followed by addition of solution of NMM (400 mM, 230 μL; 92 μmol; 10 equiv.) in DMSO and freshly prepared solution of PyOAP (110 mM; 140 μL; 15.4 μmol; 1.7 equiv.) in DMSO and the resulting yellow solution was stirred 30 min at RT. Mixture was then directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with Pbf protected product were joined, evaporated to dryness and twice co-evaporated with MeOH. Residue was dissolved in TFA (3 mL) and the resulting clear mixture was stirred 16 h at RT. Mixture was evaporated to dryness and the residue was suspended in 20% MeCN (3 mL). Mixture was filtered through syringe microfilter (RC) and the filtrate was directly purified by preparative HPLC (C18; H₂O-MeCN gradient with TFA additive). Fractions with product were joined and directly lyophilized to give product in the form of trifluoroacetate salt as white fluffy solid (the amount of TFA was set arbitrary from analogous TD1011). Yield: 11.6 mg (˜50% assuming [M]⁺[TFA]⁻·4.5TFA·xH₂O; M_R=2530; 2 steps; based on [TD897]⁺[TFA]⁻·1.1TFA·2.6H₂O). MALDI-HRMS: 1906.7973 [M]⁺ (theor. [C₇₀H₁₀₇N₃₇O₁₇Tm₁]⁺=1906.7982).

Example 10: Charts

CHART 1
Formation of 1,5-cz-[Ln(Lig)] from Lig and LnIII ions (metal dependent click-zip): conversion
determined after 1 hour at 80° C. by analytical HPLC (H2O—MeCN system with 0.1% FA additive;
detection at λ; rounded to integers; aliquots from reaction mixtures were diluted with H2O, vortexed,
centrifuged and then injected to HPLC). Initial component concentrations: 0.5 mm aq. Lig (1.0 equiv.);
1.0 mM aq. LnIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass
vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
Lig	λ, nm	LaIII	CeIII	PrIII	NdIII	SmIII	EuIII	GdIII	TbIII	DyIII	HoIII	ErIII	TmIII	YbIII	LuIII
TD425	275	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD556	275	1%	1%	1%	2%	3%	4%	5%	11%	16%	24%	37%	52%	64%	71%
TD576	280	?	?	?	?	?	?	?	?	?	?	?	?	?	?
TD582 ↓	275	0%	0%	5%	6%	12%	14%	15%	18%	18%	16%	15%	14%	12%	5%
TD604	280	0%	0%	0%	0%	0%	0%	0%	1%	1%	1%	1%	2%	2%	1%
TD647	280	1%	1%	1%	1%	3%	4%	5%	9%	13%	21%	32%	48%	61%	64%
TD669	275	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD714 *	270	0%	1%	2%	3%	5%	7%	9%	17%	23%	26%	34%	40%	40%	37%
TD722	280	0%	0%	0%	0%	1%	1%	2%	3%	5%	9%	17%	27%	38%	49%
TD728 /	275	0%	0%	0%	0%	0%	0%	0%	0%	1%	1%	1%	1%	2%	2%
TD742	285	1%	1%	1%	1%	3%	4%	5%	9%	15%	22%	34%	48%	55%	66%
TD778 ‡	285	24%	20%	13%	9%	4%	4%	4%	9%	13%	17%	25%	31%	30%	26%
TD779 ‡	280	0%	0%	0%	0%	1%	2%	3%	6%	8%	10%	12%	9%	9%	5%
TD801 ↑	275	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD827 /	275	1%	2%	2%	3%	7%	9%	11%	21%	30%	43%	56%	68%	75%	77%
TD921 ↓	275	0%	0%	5%	4%	1%	1%	0%	1%	1%	1%	1%	1%	1%	1%
TD943	280	0%	0%	0%	0%	0%	0%	0%	1%	1%	2%	2%	3%	3%	5%
TD944	270	0%	0%	0%	0%	0%	0%	0%	0%	0%	1%	1%	1%	2%	2%
TD959	275	0%	0%	0%	0%	1%	1%	1%	1%	1%	2%	3%	4%	5%	6%
TD992	275	0%	0%	0%	0%	1%	1%	1%	1%	1%	2%	2%	4%	5%	6%
TD1054	280	0%	0%	0%	1%	2%	3%	3%	6%	10%	16%	26%	39%	53%	63%
TD1063	278	0%	1%	1%	2%	3%	4%	5%	10%	15%	22%	33%	45%	53%	54%
TD1092	280	0%	0%	0%	1%	1%	2%	2%	3%	5%	7%	12%	19%	24%	26%
		0%	0%	0%	0%	2%	2%	3%	6%	8%	13%	19%	26%	30%	30%
TD1105	275	0%	0%	0%	1%	1%	1%	1%	2%	2%	3%	4%	5%	7%	8%
		0%	0%	0%	0%	0%	0%	0%	0%	0%	1%	2%	3%	5%	9%
TD1127	278	0%	0%	0%	0%	0%	1%	1%	1%	2%	3%	4%	7%	10%	13%
TD1148	280	0%	0%	0%	1%	3%	4%	5%	9%	14%	21%	33%	45%	54%	57%
		0%	0%	0%	0%	0%	0%	1%	1%	2%	3%	4%	5%	5%	6%
TD1160	280	—	—	—	—	0%	—	—	0%	—	—	—	—	—	3%
						3%			9%						61%
TD1176	285	0%	0%	1%	2%	5%	6%	7%	14%	20%	31%	46%	63%	75%	85%
TD1204	278	0%	0%	0%	0%	1%	1%	1%	2%	2%	4%	6%	11%	15%	18%
? No complex (either Ln(TD576) or 1,5-cz-[Ln(TD576)]) was detected, although consumption of the starting ligand was observed (slowest for La, fastest for Lu). Reaction mixtures did not contain visible precipitate. Addition of organic co-solvent (MeOH or MeCN) to reaction mixtures and/or HPLC aliquots did not have significant effect. This behaviour was also observed in the case of a less hydrophobic analogue TD581.
↓ Obtained data might not accurately reflect abundance of 1,5-cz-[Ln(Lig)] in the whole mixture as non-negligible variation of overall signal intensity was observed throughout the series.
↑ Propionate pendants arms detach during course of the reaction, yielding a mixture of 1,4-cz-TD801 and 1,5-TD801 and their corresponding derivatives with either one or both propionate arms removed.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
‡ Pendant arms of 1,5-cz-[Ln(Lig)] are coordinated in deprotonated iminol form (each bearing −1 charge). As a consequence, these species undergo hydrolysis to acetate arms (i.e. in situ yielding 1,5-cz-[Ln(TD647)]).
# ; Values in italics: 1,5-cz-[Ln(Lig)] with hydrolysed group in the side chain (Me ester in the case of TD1092, i-Pr ester in the case of TD1148, t-Bu ester in the case of TD1160 and Boc in the case of TD1105).
— Not performed.

CHART 2
Formation of 1,5-cz-[Ln(Lig)] from Lig and LnIII ions (metal dependent click-zip): conversion
determined after 1 week at 80° C. by analytical HPLC (H2O-MeCN system with 0.1% FA additive; detection
at λ; rounded to integers; aliquots from reaction mixtures were diluted with H2O, vortexed, centrifuged
and then injected to HPLC). Initial component concentrations: 0.5 mM aq. Lig (1.0 equiv.); 1.0 mM aq.
LnIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass vials
with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
Lig	λ, nm	LaIII	CeIII	PrIII	NdIII	SmIII	EuIII	GdIII	TbIII	DyIII	HoIII	ErIII	TmIII	YbIII	LuIII
TD425	275	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD556	275	50%	25%	64%	81%	92%	92%	91%	95%	94%	95%	95%	95%	95%	95%
TD582 ↓	275	0%	0%	17%	60%	86%	87%	86%	82%	85%	79%	74%	68%	59%	26%
TD604	280	15%	17%	16%	16%	27%	51%	50%	69%	67%	69%	66%	71%	72%	74%
TD647	280	49%	50%	69%	79%	86%	89%	92%	91%	92%	95%	95%	96%	96%	96%
TD669	275	n.d.	n.d.	n.d.	n.d.	33%	25%	24%	err.	20%	14%	12%	11%	10%	7%
TD714 *	270	4%	40%	80%	73%	82%	85%	85%	92%	91%	93%	93%	94%	93%	93%
TD722	280	2%	1%	3%	4%	9%	14%	19%	54%	65%	82%	91%	96%	96%	96%
TD728 /	275	13%	5%	23%	24%	34%	35%	32%	49%	54%	60%	72%	84%	88%	88%
TD742	285	40%	43%	66%	76%	87%	89%	91%	93%	93%	94%	94%	94%	93%	94%
TD764	278	25%	20%	35%	50%	73%	79%	86%	91%	93%	94%	95%	96%	96%	96%
TD778 ‡	285	0%	0%	0%	0%	1%	3%	11%	15%	18%	30%	32%	31%	27%	34%
TD779 ‡	280	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD801 ↑	275	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD827 /	275	46%	22%	79%	84%	91%	92%	93%	95%	96%	96%	96%	97%	97%	97%
TD921 ↓	275	0%	0%	55%	43%	42%	31%	28%	41%	37%	31%	26%	18%	15%	10%
TD943	280	5%	4%	10%	16%	29%	36%	40%	56%	65%	77%	88%	94%	97%	97%
TD944	270	4%	3%	6%	8%	16%	19%	23%	37%	51%	68%	84%	93%	95%	94%
TD959	275	18%	11%	27%	34%	48%	51%	54%	68%	76%	84%	93%	97%	98%	99%
TD992	275	22%	20%	33%	40%	55%	59%	61%	73%	81%	89%	95%	98%	99%	99%
TD1054	280	4%	4%	10%	11%	22%	28%	33%	55%	70%	79%	88%	94%	97%	98%
TD1063	278	5%	1%	35%	52%	57%	73%	74%	83%	86%	90%	93%	93%	95%	95%
TD1092	280	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
		40%	37%	62%	73%	88%	91%	92%	93%	94%	94%	94%	95%	96%	97%
TD1105	275	0%	0%	0%	0%	1%	1%	2%	1%	0%	1%	1%	1%	1%	1%
		11%	8%	21%	23%	44%	49%	57%	74%	82%	87%	92%	94%	97%	98%
TD1127	278	18%	7%	15%	25%	46%	53%	56%	72%	80%	86%	91%	93%	95%	97%
TD1148	280	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
		36%	27%	61%	71%	86%	90%	90%	91%	93%	94%	94%	95%	95%	96%
TD1160	280	—	—	—	—	0%	—	—	0%	—	—	—	—	—	0%
						85%			89%						91%
TD1176	285	73%	60%	82%	85%	92%	93%	91%	94%	96%	96%	96%	96%	97%	96%
TD1204	278	0%	0%	0%	1%	4%	5%	5%	10%	17%	23%	39%	62%	76%	83%
Legend:
↓ Obtained data might not accurately reflect abundance of 1,5-cz-[Ln(Lig)] in the whole mixture as non-negligible variation of overall signal intensity was observed throughout the series.
↑ Propionate pendants arms detach during course of the reaction, yielding a mixture of 1,4-cz-TD801 and 1,5- TD801 and their corresponding derivatives with either one or both propionate arms removed.
n.d. Could not be precisely determined due to signal overlapping and/or decomplexation during HPLC analysis.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
‡ Pendant arms of 1,5-cz-[Ln(Lig)] are coordinated in deprotonated iminol form (each bearing −1 charge). As a consequence, these species undergo hydrolysis to acetate arms (i.e. in situ yielding 1,5-cz-[Ln(TD647)]).
err. Accidental evaporation of the whole reaction solvent due to untighten vial cap.
Values in italics: 1,5-cz-[Ln(Lig)] with hydrolysed group in the side chain (Me ester in the case of TD1092, i-Pr ester in the case of TD1148, t-Bu ester in the case of TD1160 and Boc in the case of TD1105).
— Not performed.

CHART 3
Formation of 1,5-cz-[Ln(Lig)] from Lig and LnIII ions (metal dependent click-zip): conversion
determined after 1 hour at 80° C. (A) and 18 hours at 80° C. (B) by analytical HPLC (H2O-MeCN
system with 0.1% FA additive; detection at λ; rounded to integers; aliquots from reaction mixtures were diluted
with H2O, vortexed, centrifuged and then injected to HPLC). Initial component concentrations: 0.5 mM aq.
Lig (1.0 equiv.); 1.0 mM aq. LnIII (2.0 equiv.); 50 mM aq. MES/NaOH buffer pH 5.2 (100 equiv.). Performed
in glass vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
A	λ, nm	LaIII	CeIII	PrIII	NdIII	SmIII	EuIII	GdIII	TbIII	DyIII	HoIII	ErIII	TmIII	YbIII	LuIII
TD750	270	—	—	—	—	—	—	3%	—	—	—	—	—	—	19%
B	λ, nm	LaIII	CeIII	PrIII	NdIII	SmIII	EuIII	GdIII	TbIII	DyIII	HoIII	ErIII	TmIII	YbIII	LuIII
TD750	270	—	—	—	—	—	—	9%	—	—	—	—	—	—	71%
Legend:
— Not performed.

CHART 4
Formation of 1,5-cz-[M(Lig)] from Lig and MIII ions (metal
dependent click-zip): conversion determined after 1 hour at 80°
C. by analytical HPLC (H2O—MeCN system with 0.1% FA additive;
detection at λ; rounded to integers; aliquots from reaction mixtures
were diluted with H2O, vortexed, centrifuged and then injected to
HPLC). Initial component concentrations: 0.5 mm aq. Lig (1.0
equiv.); 1.0 mM aq. MIII (2.0 equiv.); 50 mM aq. MOPS/NaOH
buffer pH 7.0 (100 equiv.). Performed in glass vials with magnetic
stirrers. Metal ions are sorted by decreasing ionic radius.
Lig	λ, nm	†BiIII	YIII	InIII	ScIII	RuIII	IrIII	GaIII
TD425	275	—	0%	—	0%	—	—	—
TD556	275	—	22%	—	2%	—	—	—
TD582	275	—	11%	—	0%	—	—	—
TD604	280	—	1%	—	1%	—	—	—
TD639	275	—	0%	—	0%	—	—	—
TD647	280	29%	20%	0%	7%	—	—	0%
TD669	275	—	0%	—	0%	—	—	—
TD714 *	270	—	22%	—	prec.	—	—	—
TD722	280	—	9%	—	3%	—	—	—
TD728 /	275	5%	1%	—	0%	0%	0%	—
TD742	285	—	22%	—	7%	—	—	—
TD764	278	31%	—	—	—	—	—	—
TD778 ‡	285	—	17%	—	0%	—	—	—
TD779 ‡	280	—	4%	—	0%	—	—	—
TD801	275	—	0%	—	0%	—	—	—
TD827 /	275	—	42%	—	2%	—	—	—
TD921	275	—	0%	—	0%	—	—	—
TD943	280	—	1%	—	0%	—	—	—
TD944	270	—	1%	—	0%	—	—	—
TD959	275	—	1%	—	0%	—	—	—
TD992	275	—	2%	—	0%	—	—	—
TD1054	280	—	16%	—	4%	—	—	—
TD1063	278	—	20%	—	1%	—	—	—
TD1063	278	—	20%	—	1%	—	—	—
TD1092	280	—	6%	—	1%	—	—	—
			12%		0%
TD1105	275	—	2%	—	0%	—	—	—
			1%		0%
TD1127	278	—	2%	—	0%	—	—	—
TD1148	280	—	18%	—	0%	—	—	—
			3%		0%
TD1160	280	—	1%	—	—	—	—	—
			17%
TD1176	285	—	30%	—	6%	—	—	—
TD1204	278	—	3%	—	0%	—	—	—
Legend:
prec. Could not be reasonably determined due to formation of precipitate.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
† Performed in a mixture of 4% DMSO in aq. MOPS/NaOH Buffer pH 7.0.
‡ Pendant arms of 1,5-cz-[Ln(Lig)] are coordinated in deprotonated iminol form (each bearing −1 charge). As a consequence, these species undergo hydrolysis to acetate arms (i.e. in situ yielding 1,5-cz-[Ln(TD647)]).
Values in italics: 1,5-cz-[Ln(Lig)] with hydrolysed group in the side chain (Me ester in the case of TD1092, i-Pr ester in the case of TD1148, t-Bu ester in the case of TD1160 and Boc in the case of TD1105).
— Not performed.

CHART 5
Formation of 1,5-cz-[M(Lig)] from Lig and MIII (metal dependent
click-zip): conversion determined after 1 week at 80° C. by analytical
HPLC (H2O—MeCN system with 0.1% FA additive; detection at λ;
rounded to integers; aliquots from reaction mixtures were diluted
with H2O, vortexed, centrifuged and then injected to HPLC). Initial
component concentrations: 0.5 mm aq. Lig (1.0 equiv.); 1.0 mM aq.
MIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.).
Performed in glass vials with magnetic stirrers. Metal ions are
sorted by decreasing ionic radius.
Lig	λ, nm	†BiIII	YIII	InIII	ScIII	RuIII	IrIII	GaIII
TD425	275	—	0%	—	0%	—	—	—
TD556	275	—	95%	—	23%	—	—	—
TD582	275	—	68%	—	0%	—	—	—
TD604	280	—	58%	—	10%	—	—	—
TD639	275	—	0%	—	0%	—	—	—
TD647	280	73%	93%	8%	35%	—	—	0%
TD669	275	—	12%	—	0%	—	—	—
TD714 *	270	—	89%	—	prec.	—	—	—
TD722	280	—	71%	—	14%	—	—	—
TD728 /	275	29%	50%	—	2%	0%	0%	—
TD742	285	—	94%	—	52%	—	—	—
TD764	278	85%	95%	—	5%	—	—	—
TD778 ‡	285	—	27%	—	0%	—	—	—
TD779 ‡	280	—	0%	—	0%	—	—	—
TD801	275	—	0%	—	0%	—	—	—
TD827 /	275	—	96%	—	55%	—	—	—
TD921	275	—	14%	—	0%	—	—	—
TD943	280	—	74%	—	5%	—	—	—
TD944	270	—	63%	—	4%	—	—	—
TD959	275	—	82%	—	1%	—	—	—
TD992	275	—	87%	—	2%	—	—	—
TD1054	280	—	80%	—	61%	—	—	—
TD1063	278	—	91%	—	8%	—	—	—
TD1092	280	—	0%	—	0%	—	—	—
			95%		17%
TD1105	275	—	0%	—	0%	—	—	—
			87%		60
TD1127	278	—	83%	—	29%	—	—	—
TD1148	280	—	0%	—	0%	—	—	—
			94%		11%
TD1160	280	—	0%	—	—	—	—	—
			90%
TD1176	285	—	95%	—	31%	—	—	—
TD1204	278	—	22%	—	16%	—	—	—
Legend:
prec. Could not be reasonably determined due to formation of precipitate.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
† Performed in a mixture of 4% DMSO in aq. MOPS/NaOH Buffer pH 7.0.
‡ Pendant arms of 1,5-cz-[Ln(Lig)] are coordinated in deprotonated iminol form (each bearing −1 charge). As a consequence, these species undergo hydrolysis to acetate arms (i.e. in situ yielding 1,5-cz-[Ln(TD647)]).
Values in italics: 1,5-cz-[Ln(Lig)] with hydrolysed group in the side chain (Me ester in the case of TD1092, i-Pr ester in the case of TD1148, t-Bu ester in the case of TD1160 and Boc in the case of TD1105).
— Not performed.

CHART 6
Formation of 1,5-cz-[M(Lig)] from Lig and MII ions (metal dependent click-zip):
conversion determined after 1 hour at 80° C. by analytical HPLC (H2O—MeCN
system with 0.1% FA additive; detection at λ; rounded to integers; aliquots from
reaction mixtures were diluted with H2O, vortexed, centrifuged and then injected to
HPLC). Initial component concentrations: 0.5 mm aq. Lig (1.0 equiv.); 1.0 mM aq.
MII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass
vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
Lig	λ, nm	BaII	PbII	SrII	CaII	CdII	PdII	MnII	PtII	ZnII	CuII	NiII
TD639	275	0%	—	0%	0%	—	—	—	—	—	—	—
TD647	280	0%	2%	0%	16%	64%	—	—	—	0%	prec.	0%
TD714 *	270	0%	—	0%	0%	89%	—	—	—	—	—	—
TD728 /	275	—	0%	—	0%	1%	1%	0%	0%	—	—	—
TD764	278	—	1%	—	16%	53%	10%	1%	—	—	—	—
TD921	275	0%	—	0%	0%	92%	—	—	—	—	—	—
TD959	275	—	—	—	1%	2%	—	—	—	—	—	—
Legend:
prec. Could not be reasonably determined due to formation of precipitate.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
— Not performed.

CHART 7
Formation of 1,5-cz-[M(Lig)] from Lig and MII ions (metal dependent click-zip):
conversion determined after 1 week at 80° C. by analytical HPLC (H2O—MeCN
system with 0.1% FA additive; detection at λ; rounded to integers; aliquots from
reaction mixtures were diluted with H2O, vortexed, centrifuged and then injected to
HPLC). Initial component concentrations: 0.5 mM aq. Lig (1.0 equiv.); 1.0 mM aq.
MII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass
vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
Lig	λ, nm	BaII	PbII	SrII	CaII	CdII	PdII	MnII	PtII	ZnII	CuII	NiII
TD639	275	0%	—	0%	0%	—	—	—	—	—	—	—
TD647	280	0%	54%	0%	87%	86%	—	—	—	0%	prec.	0%
TD714	270	0%	—	0%	6%	92%	—	—	—	—	—	—
TD728 /	275	—	14%	—	37%	36%	1%	1%	0%	—	—	—
TD764	278	—	37%	—	95%	96%	9%	35%	—	—	—	—
TD921	275	0%	—	0%	0%	96%	—	—	—	—	—	—
TD959	275	—	—	—	83%	96%	—	—	—	—	—	—
Legend:
prec. Could not be reasonably determined due to formation of precipitate.
* Sum of two diastereoisomers.
/ Performed in a mixture of 50% i-PrOH in aq. MOPS/NaOH Buffer pH 7.0.
— Not performed.

CHART 8
Formation of 1,5-cz-[Ln(Lig)] from 1,5-cz-Lig (metal dependent direct complexation): conversion determined
after 1 hour at 80° C. (A), 1 week at 80° C. (B) and~6 months at 80° C. (B) by analytical HPLC
(H2O—MeCN system with 0.1% FA additive; detection at λ; rounded to integers; aliquots from reaction mixtures were
diluted with H2O, vortexed, centrifuged and then injected to HPLC). Initial component concentrations: 0.5 mM aq.
1,5-cz-Lig (1.0 equiv.); 1.0 mM aq. LnIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.).
Performed in glass vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
	λ, nm	LaIII	CeIII	PrIII	NdIII	SmIII	EuIII	GdIII	TbIII	DyIII	HoIII	ErIII	TmIII	YbIII	LuIII
A
TD650	280	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
B
TD650	280	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
C
TD650	280	—	—	—	—	—	—	0%	—	—	—	—	—	—	0%
Legend:
— Not performed.

CHART 9
Formation of 1,5-cz-[Ln(Lig)] from 1,5-cz-Lig (metal dependent direct complexation): conversion
determined after 1 min at RT (A), 1 hour at RT (B), 1 hour at 80° C. (C) and 1 week at 80°
C. (D) by analytical HPLC (H2O—MeCN system with 0.1% FA additive; detection at λ; rounded to
integers; aliquots from reaction mixtures were diluted with H2O, vortexed, centrifuged and then injected to
HPLC). Initial component concentrations: 0.5 mM aq. 1,5-cz-Lig (1.0 equiv.); 1.0 mM aq. MII or
MIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass vials with
magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
	λ, nm	BaII	PbII	SrII	†BiIII	CaII	CdII	YIII	InIII	ScIII	ZnII	CuII	NiII	GaII
A
TD650	280	—	98%	—	—	—	—	—	—	—	—	43%	—	—
B
TD650	280	—	99%	—	2%	0%	58%	—	—	—	59%	47%	0%	—
C
TD650	280	—	98%	—	96%	23%	98%	—	—	—	91%	49%	9%	—
D
TD650	280	0%	98%	0%	90%	96%	99%	0%	0%	0%	99%	78%	11%	0%
Legend:
†Performed in a mixture of~4% DMSO in aq. MOPS/NaOH Buffer pH 7.0.
— Not performed.

CHART 10

Formation of 1,4-cz-[Ln(Lig)] from 1,4-cz-Lig (metal dependent direct complexation): conversion

determined after 1 week at 80° C. (A) by analytical HPLC (H2O—MeCN system with 0.1% FA additive;

detection at λ; rounded to integers; aliquots from reaction mixtures were diluted with H2O, vortexed,

centrifuged and then injected to HPLC). Initial component concentrations: 0.5 mm aq. 1,4-cz-Lig (1.0 equiv.);

1.0 mM aq. LnIII (2.0 equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass

vials with magnetic stirrers. Metal ions are sorted by decreasing ionic radius.

A

λ, nm

LaIII

CeIII

PrIII

NdIII

SmIII

EuIII

GdIII

TbIII

DyIII

HoIII

ErIII

TmIII

YbIII

LuIII

TD622

275

0%

0%

3%

6%

34%

45%

46%

61%

66%

68%

70%

71%

51%

53%

CHART 11
Formation of 1,4-cz-[Ln(Lig)] from 1,4-cz-Lig (metal dependent direct complexation):
conversion determined after 1 hour at 80° C. (A) and 1 week at 80° C. (B) by analytical
HPLC (H2O—MeCN system with 0.1% FA additive; detection at λ; rounded to integers; aliquots
from reaction mixtures were diluted with H2O, vortexed, centrifuged and then injected to HPLC). Initial
component concentrations: 0.5 mm aq. 1,4-cz-Lig (1.0 equiv.); 1.0 mM aq. MII or MIII (2.0
equiv.); 50 mM aq. MOPS/NaOH buffer pH 7.0 (100 equiv.). Performed in glass vials with
magnetic stirrers. Metal ions are sorted by decreasing ionic radius.
	λ, nm	BaII	PbII	SrII	†BiIII	CaII	CdII	YIII	InIII	ScIII	ZnII	CuII	NiII	GaII
A
TD622	275	—	98%	—	98%	20%	98%	—	—	—	88%	42%	41%	—
B
TD622	275	0%	99%	0%	91%	21%	99%	51%	13%	0%	99%	48%	44%	8%
Legend:
†Performed in a mixture of~4% DMSO in aq. MOPS/NaOH Buffer pH 7.0.
— Not performed.

CHART 12
Formation of 1,5-cz-[Lu(Lig)] from Lig (metal dependent click-zip) with various
absolute concentrations: conversion determined after 1 hour at 80° C. (A), 1 day
at 80° C. (B) and 1 week at 80° C. (C) by analytical HPLC (H2O—MeCN system
with 0.1% FA additive; detection at 280 nm; rounded to integers; aliquots from reaction mixtures
were diluted with H2O, vortexed, centrifuged and then injected to HPLC). Performed with
constant ratio of reagents (Lig:LuIII:aq. MOPS/NaOH buffer pH 7.0 = 1.0:1.5:50).
Performed in glass vials with magnetic stirrers.
Lig, mM	5.0 × 101	5.0 × 100	5.0 × 10−1	5.0 × 10−2	5.0 × 10−3
LuIII, mM	7.5 × 101	7.5 × 100	7.5 × 10−1	7.5 × 10−2	7.5 × 10−3
aq. MOPS/NaOH buffer pH 7.0, mM	2.5 × 103	2.5 × 102	2.5 × 101	2.5 × 100	2.5 × 10−1
TD647 (A)	71%	74%	70%	60%	15%
TD647 (B)	84%	96%	97%	96%	59%
TD647 (C)	86%	96%	97%	96%	57%

CHART 13
pH dependent formation of 1,5- and 1,4-cz-Lig isomers from Lig (pH dependent click-zip): conversion
determined after 1 hour at 80° C. (A) and 1 day at 80° C. (B) by analytical HPLC (H2O—MeCN
system with 0.1% FA additive; detection at λ; rounded to integers; aliquots from reaction mixtures were
diluted with H2O, vortexed and then injected to HPLC). Initial component concentrations: 0.5 mM aq.
Lig (1.0 equiv.); 1.0M HClO4 (pH ~0)/0.1M HClO4 (pH ~1)/50 mM aq. buffer (100 equiv.).
Performed in glass vials with magnetic stirrers.
	System	aq. HClO4	aq. Citrate/NaOH buffer	aq. Borate/NaOH buffer
	λ, nm	pH	~0	~1	2.2	3.0	3.8	4.6	5.4	6.2	7.0	8.6	9.4	10.2
A
TD425	275	1.5	13%	13%	13%	10%	3%	1%	1%	0%	0%	0%	1%	1%
		1.4	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
TD647	280	1.5	9%	44%	17%	6%	1%	1%	1%	1%	1%	2%	8%	17%
		1.4	2%	3%	2%	1%	1%	1%	1%	1%	2%	3%	3%	2%
B
TD425	275	1.5	88%	90%	93%	89%	57%	15%	6%	6%	8%	10%	11%	12%
		1.4	0%	0%	0%	0%	0%	0%	0%	1%	4%	5%	4%	2%
TD647	280	1.5	72%	91%	88%	69%	22%	13%	12%	11%	19%	26%	60%	80%
		1.4	8%	5%	6%	6%	6%	5%	6%	12%	23%	32%	17%	5%

CHART 14
Alkali metal dependent formation of 1,5-cz-Lig and 1,4-cz-Lig isomers
from Lig (alkali metal dependent click-zip) at pH 10.2: conversion
determined after 1 hour at 80° C. (A) and 1 day at 80° C. (B)
by analytical HPLC (H2O—MeCN system with 0.1% FA additive;
detection at λ; rounded to integers; aliquots from reaction mixtures
were diluted with H2O, vortexed and then injected to HPLC). Initial
component concentrations: 0.5 mm aq. Lig (1.0 equiv.); 50 mM aq.
Borate/(MI)2CO3 buffer (MI = LiI − CsI; 100 equiv.).
Performed in plastic Eppendorf test tubes with magnetic stirrers.
	System	aq. Borate/(MI)2CO3 buffer (pH 10.2)
A	λ, nm	MI	LiI	NaI	KI	RbI	CsI
TD425	275	1.5	0%	1%	0%	1%	1%
		1.4	0%	0%	1%	1%	1%
TD647	280	1.5	0%	15%	1%	0%	0%
		1.4	0%	1%	2%	2%	2%
TD921	275	1.5	12%	30%	2%	2%	2%
		1.4	1%	2%	2%	2%	2%
	System	aq. Borate/(MI)2CO3 buffer (pH 10.2)
B	λ, nm	MI	ΨLiI	NaI	KI	RbI	CsI
TD425	275	1.5	2%	9%	10%	10%	11%
		1.4	0%	1%	10%	10%	10%
TD647	280	1.5	9%	85%	10%	6%	7%
		1.4	2%	1%	40%	41%	39%
TD582	275	1.5	53%	69%	11%	10%	10%
		1.4	3%	2%	25%	25%	26%
TD581	280	1.5	10%	25%	7%	7%	6%
		1.4	19%	26%	32%	32%	31%
TD703	270	1.5	24%	75%	14%	14%	13%
		1.4	14%	10%	20%	20%	20%
TD714	270	1.5	15%	81%	10%	9%	9%
		1.4	12%	7%	46%	45%	44%
TD921	275	1.5	86%	89%	23%	21%	21%
		1.4	6%	4%	31%	31%	31%
Legend:
ΨReaction mixture contained a visible precipitate, which was shown to be analyte free (all forms).

CHART 15
Relaxitivities of GdIII chelates TD451 and
TD527 determined by standard
inversion recovery pulse sequence on relaxometer
(the minispec mq20 NMR analyzer; 0.5 T; Bruker) at 40.0° C.
(concentration of chelates: 1.0 mM in aq. MOPS/NaOH buffer, pH 7.0).
species	formally	relaxivity, mM−1s−1
TD451	[Gd(TD647)])	2.39
TD527	1,5-cz-	1.48
	[Gd(TD647)])

CHART 17
Dissociation of chelates in aq. 6.0M HCl at 80° C. (acid decomplexation kinetic inertness): fraction of intact
chelate determined after 1 hour, 1 day, 1 week and 1 month by analytical HPLC (H2O—MeCN system with 0.1% FA additive;
detection at 280 nm; rounded to integers; aliquots from reaction mixtures were appropriately diluted to prevent re-
complexation, vortexed, centrifuged and then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	formally	λ, nm	1 hour	1 day	1 week	1 month	t1/2, hours f
TD875 A	1,4-cz-[GdIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD874 A	1,4-cz-[LuIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD900 A	1,4-cz-[CdII(TD647)]	278	0%	0%	0%	0%	too unstable
TD651 B	1,5-cz-[LaIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD870 B	1,5-cz-[CeIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD869 B	1,5-cz-[PrIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD868 B	1,5-cz-[NdIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD867 B	1,5-cz-[SmIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD599 B	1,5-cz-[EuIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD527 B	1,5-cz-[GdIII(TD647)]	278	2%	0%	0%	0%	1.7E −1
TD600 B	1,5-cz-[TbIII(TD647)]	278	72%	0%	0%	0%	2.7E 0
TD866 B	1,5-cz-[DyIII(TD647)]	278	95%	25%	0%	0%	1.2E 1 ± 1.3E−1
TD648 B	1,5-cz-[HoIII(TD647)]	278	99%	81%	17%	0%	6.8E 1 ± 2.7E0
TD865 B	1,5-cz-[ErIII(TD647)]	278	99%	95%	71%	24%	3.4E 2 ± 2.5E0
TD601 B	1,5-cz-[TmIII(TD647)]	278	100%	99%	92%	69%	1.4E 3 ± 1.2E1
TD602 B	1,5-cz-[YbIII(TD647)]	278	100%	100%	98%	90%	4.7E 3 ± 2.1E1
TD522 B	1,5-cz-[LuIII(TD647)] ∞	278	100%	100%	99%	98%	3.3E 4 ± 1.4E3
TD649 B	1,5-cz-[YIII(TD647)]	278	98%	69%	7%	0%	4.5E 1 ± 3.1E−1
TD876 A	1,5-cz-[PbII(TD647)]	278	0%	0%	0%	0%	too unstable
TD863 A	1,5-cz-[CaII(TD647)]	278	0%	0%	0%	0%	too unstable
TD880 A	1,5-cz-[CdII(TD647)]	278	43%	0%	0%	0%	1.2E 0
TD890 A	1,5-cz-[ZnII(TD647)]	278	0%	0%	0%	0%	too unstable
TD624-La A, *	[LaIII(p-NO2BnDOTA)]	285	0%	0%	0%	0%	too unstable
TD624-Gd A, *	[GdIII(p-NO2BnDOTA)]	285	0%	0%	0%	0%	too unstable
TD624-Lu A, *	[LuIII(p-NO2BnDOTA)]	285	0%	0%	0%	0%	too unstable
TD925 B	1,5-cz-[GdIII(TD921)]	275	77%	0%	0%	0%	2.6E 0
TD748 B	1,5-cz-[LuIII(TD742)] ∞	285	100%	100%	100%	97%	1.5E 4 ± 2.9E2
TD735 B	1,5-cz-[LuIII(TD722)] ∞	280	100%	100%	99%	98%	2.3E 4 ± 8.3E2
TD739 B, *	--	275	100%	90%	43%	15%	1.5E 2 ± 2.6E1
TD734 B, *	1,5-cz-[LuIII(TD714)] ∞	280	100%	100%	98%	95%	1.6E 4 ± 1.5E3
TD737 B	1,5-cz-[LuIII(TD728)]	280	100%	100%	99%	98%	—
			(87%/13%)	(3%/97%)	(0%/99%)	(0%/98%)
Legend:
A Aliquots (2 μL) were neutralized with 500 mM FA/NaOH buffer (pH 3.6; 200 μL) prior measurement.
B Aliquots (2 μL) were neutralized with 500 mM MOPS/NaOH buffer (pH 7.0; 200 μL) prior measurement.
f Dissociation data were fitted by exponential decay (equation y = exp(−x/t); y = fraction of intact chelate; x = time; t = decay constant). Chelate stability is expressed as half-life t1/2, (in hours; highlighted bold), derived from decay constant (t1/2 = ln(2) × t). The error of the fitting is not displayed for single data point fitting.
* Sum of two diastereoisomers.
Stock solutions preparation: In Eppendorf tube (0.5 mL), 2,2′,2″,2″′-(2-(4-nitrobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10- tetrayl)tetraacetic acid tetrahydrochloride (10.0 mM in H2O; 100 μL; 1 μmol; 1.0 equiv.) was mixed with corresponding aq. LnCl3 (100 mM; 23.5 μ L; 1.1 μmol; 1.1 equiv.), H2O (59 μL) and aq. NaOH (400 mM; 17.5 μL; 7.0 μmol; 7.0 equiv.). The resulting mixtures were then stirred 16 h at RT (full conversion was confirmed by LC-MS) followed by centrifugation. Supernatants were then directly used as stock solutions for the dissociation assay.
-- Isolated only as a click-zipped complex (no parent ligand exists).
∞ Additional data points were collected over the period of 6 months (included in the fitting).
Values in brackets: chelate with intact TIPS group/chelate with hydrolysed TIPS group.
— The half-life cannot be rigorously determined due to a parallel hydrolysis of TIPS group.

CHART 18
Dissociation of chelates in aq. 1.0M HCl at 80° C. (acid decomplexation kinetic inertness):
fraction of intact chelate determined after 1 hour, 1 day, 1 week and 1 month by analytical HPLC
(H2O—MeCN system with 0.1% FA additive; detection at 280 nm; rounded to integers; aliquots
from reaction mixtures were neutralized with aq. MOPS/NaOH Buffer pH 7.0, vortexed, centrifuged
and then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	formally	λ, nm	1 hour	1 day	1 week	1 month	t1/2, hours f
TD875 A	1,4-cz-[GdIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD874 A	1,4-cz-[LuIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD900 A	1,4-cz-[CdII(TD647)]	278	0%	0%	0%	0%	too unstable
TD651 B	1,5-cz-[LaIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD870 B	1,5-cz-[CeIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD869 B	1,5-cz-[PrIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD868 B	1,5-cz-[NdIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD867 B	1,5-cz-[SmIII(TD647)]	278	62%	0%	0%	0%	1.5E 0
TD599 B	1,5-cz-[EuIII(TD647)]	278	92%	10%	0%	0%	7.3E 0 ± 2.6E−1
TD527 B	1,5-cz-[GdIII(TD647)]	278	98%	58%	1%	0%	3.0E 1 ± 4.9E−1
TD600 B	1,5-cz-[TbIII(TD647)]	278	99%	96%	78%	23%	3.7E 2 ± 3.2E1
TD866 B	1,5-cz-[DyIII(TD647)]	278	100%	99%	96%	87%	3.6E 3 ± 5.0E1
TD648 B	1,5-cz-[HoIII(TD647)]	278	100%	100%	99%	96%	1.3E 4 ± 2.6E2
TD865 B	1,5-cz-[ErIII(TD647)]	278	100%	100%	100%	99%	5.9E 4 ± 1.1E3
TD601 B	1,5-cz-[TmIII(TD647)]	278	100%	100%	100%	100%	too stable
TD602 B	1,5-cz-[YbIII(TD647)]	278	100%	100%	100%	100%	too stable
TD522 B	1,5-cz-[LuIII(TD647)]	278	100%	100%	100%	100%	too stable
TD649 B	1,5-cz-[YIII(TD647)]	278	100%	100%	98%	92%	5.9E 3 ± 1.4E2
TD876 A	1,5-cz-[PbII(TD647)]	278	0%	0%	0%	0%	too unstable
TD863 A	1,5-cz-[CaII(TD647)]	278	0%	0%	0%	0%	too unstable
TD880 A	1,5-cz-[CdII(TD647)]	278	100%	99%	90%	63%	1.1E 3 ± 7.7E0
TD890 A	1,5-cz-[ZnII(TD647)]	278	0%	0%	0%	0%	too unstable
TD624-La A, *	[LaIII(p-NO2BnDOTA)]	285	0%	0%	0%	0%	too unstable
TD624-Gd A, *	[GdIII(p-NO2BnDOTA)]	28	15%	0%	0%	0%	3.7E −1
TD624-Lu A, *	[LuIII(p-NO2BnDOTA)]	285	12%	0%	0%	0%	3.3E −1
TD925 B	1,5-cz-[GdIII(TD921)]	275	100%	82%	21%	0%	7.7E 1 ± 2.3E0
Legend:
A Aliquots (2 μL) were neutralized with 125 mM FA/NaOH buffer (pH 3.6; 200 μL) prior measurement.
B Aliquots (2 μL) were neutralized with 500 mM MOPS/NaOH buffer (pH 7.0; 200 μL) prior measurement.
f Dissociation data were fitted by exponential decay (equation y = exp(−x/t); y = fraction of intact chelate; x = time; t = decay constant). Chelate stability is expressed as half-life t1/2, (in hours; highlighted bold), derived from decay constant (t1/2 = ln(2) × t). The error of the fitting is not displayed for single data point fitting.
* Sum of two diastereoisomers.
Stock solutions preparation: In Eppendorf tube (0.5 mL), 2,2′,2″,2″′-(2-(4-nitrobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid tetrahydrochloride (10.0 mM in H2O; 100 μL; 1 μmol; 1.0 equiv.) was mixed with corresponding aq. LnCl3 (100 mM; 23.5 μ L; 1.1 μmol; 1.1 equiv.), H2O (59 μL) and aq. NaOH (400 mM; 17.5 μL; 7.0 μmol; 7.0 equiv.). The resulting mixtures were then stirred 16 h at RT (full conversion was confirmed by LC-MS) followed by centrifugation. Supernatants were then directly used as stock solutions for the dissociation assay.

CHART 19
Dissociation of chelates in aq. 0.1M HCl at 80° C. (acid decomplexation kinetic
inertness): fraction of intact chelate determined after 1 hour, 1 day, 1 week and 1 month
by analytical HPLC (H2O—MeCN system with 0.1% FA additive; detection at 280 nm; rounded
to integers; aliquots from reaction mixtures were diluted with H2O, vortexed and
then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	formally	λ, nm	1 hour	1 day	1 week	1 month	t1/2, hours f
TD875 A	1,4-cz-[GdIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD874 A	1,4-cz-[LuIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD900 A	1,4-cz-[CdII(TD647)]	278	56%	0%	0%	0%	1.2E 0
TD651 B	1,5-cz-[LaIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD870 B	1,5-cz-[CeIII(TD647)]	278	0%	0%	0%	0%	too unstable
TD869 B	1,5-cz-[PrIII(TD647)]	278	23%	0%	0%	0%	4.7E −1
TD868 B	1,5-cz-[NdIII(TD647)]	278	76%	0%	0%	0%	1.2E 0
TD867 B	1,5-cz-[SmIII(TD647)]	278	99%	86%	35%	1%	1.1E 2 ± 7.5E−1
TD599 B	1,5-cz-[EuIII(TD647)]	278	100%	97%	83%	21%	3.8E 2 ± 5.8E1
TD527 B	1,5-cz-[GdIII(TD647)]	278	100%	99%	95%	82%	2.5E 3 ± 3.7E1
TD600 B	1,5-cz-[TbIII(TD647)]	278	100%	100%	99%	99%	3.2E 4 ± 3.3E3
TD866 B	1,5-cz-[DyIII(TD647)]	278	100%	100%	100%	100%	9.5E 4 ± 3.0E3
TD648 B	1,5-cz-[HoIII(TD647)]	278	100%	100%	100%	100%	too stable
TD865 B	1,5-cz-[ErIII(TD647)]	278	100%	100%	100%	100%	too stable
TD601 B	1,5-cz-[TmIII(TD647)]	278	100%	100%	100%	100%	too stable
TD602 B	1,5-cz-[YbIII(TD647)]	278	100%	100%	100%	100%	too stable
TD522 B	1,5-cz-[LuIII(TD647)]	278	100%	100%	100%	100%	too stable
TD649 B	1,5-cz-[YIII(TD647)]	278	100%	100%	100%	100%	too stable
TD876 A	1,5-cz-[PbII(TD647)]	278	0%	0%	0%	0%	too unstable
TD863 A	1,5-cz-[CaII(TD647)]	278	0%	0%	0%	0%	too unstable
TD880 A	1,5-cz-[CdII(TD647)]	278	100%	100%	100%	100%	too stable
TD890 A	1,5-cz-[ZnII(TD647)]	278	46%	0%	0%	0%	4.7E −1
TD624-La A, *	[LaIII(p-NO2BnDOTA)]	285	9%	0%	0%	0%	2.9E −1
TD624-Gd A, *	[GdIII(p-NO2BnDOTA)]	285	88%	2%	0%	0%	4.9E 0 ± 2.9E−1
TD624-Lu A, *	[LuIII(p-NO2BnDOTA)]	285	76%	2%	0%	0%	2.5E 0 ± 9.6E−2
TD925 B	1,5-cz-[GdIII(TD921)]	275	100%	98%	90%	60%	9.9E 2 ± 2.2E1
Legend:
A Aliquots (2 μL) were diluted with H2O (200 μL) prior measurement.
B Aliquots (2 μL) were neutralized with 500 mM MOPS/NaOH buffer (pH 7.0; 200 μL) prior measurement.
f Dissociation data were fitted by exponential decay (equation y = exp(−x/t); y = fraction of intact chelate; x = time; t = decay constant). Chelate stability is expressed as half-life t1/2, (in hours; highlighted bold), derived from decay constant (t1/2 = ln(2) × t). The error of the fitting is not displayed for single data point fitting.
* Sum of two diastereoisomers.
Stock solutions preparation: In Eppendorf tube (0.5 mL), 2,2′,2″,2″′-(2-(4-nitrobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid tetrahydrochloride (10.0 mM in H2O; 100 μL; 1 μmol; 1.0 equiv.) was mixed with corresponding aq. LnCl3 (100 mM; 23.5 μ L; 1.1 μmol; 1.1 equiv.), H2O (59 μL) and aq. NaOH (400 mM; 17.5 μL; 7.0 μmol; 7.0 equiv.). The resulting mixtures were then stirred 16 h at RT (full conversion was confirmed by LC-MS) followed by centrifugation. Supernatants were then directly used as stock solutions for the dissociation assay.

CHART 20
Dissociation of chelates in aq. 0.1M HCl at RT (acid decomplexation kinetic inertness):
fraction of intact chelate determined after 1 hour, 1 day, 1 week and 1 month by analytical
HPLC (H2O—MeCN system with 0.1% FA additive; detection at 280 nm; rounded to integers;
aliquots from reaction mixtures were diluted with H2O, vortexed and then injected
to HPLC). Performed in glass vials with magnetic stirrers.
chelate	formally	λ, nm	1 hour	1 day	1 week	1 month	t1/2, hours f
TD875 A	1,4-cz-[GdIII(TD647)]	278	98%	58%	6%	0%	3.2E 1 ± 2.1E0
TD874 A	1,4-cz-[LuIII(TD647)]	278	99%	68%	14%	0%	5.1E 1 ± 4.8E0
TD900 A	1,4-cz-[CdII(TD647)]	278	100%	99%	91%	63%	1.3E 3 ± 5.8E0
TD651 B	1,5-cz-[LaIII(TD647)]	278	76%	4%	0%	0%	2.5E 0 ± 2.5E−1
TD870 B	1,5-cz-[CeIII(TD647)]	278	95%	37%	0%	0%	1.7E 1 ± 2.9E−1
TD869 B	1,5-cz-[PrIII(TD647)]	278	98%	71%	12%	0%	5.2E 1 ± 2.2E0
TD868 B	1,5-cz-[NdIII(TD647)]	278	99%	90%	54%	2%	1.8E 2 ± 1.2E1
TD867 B	1,5-cz-[SmIII(TD647)]	278	100%	100%	99%	96%	1.3E 4 ± 4.4E2
TD599 B	1,5-cz-[EuIII(TD647)]	278	100%	100%	100%	100%	too stable
TD527 B	1,5-cz-[GdIII(TD647)]	278	100%	100%	100%	100%	too stable
TD600 B	1,5-cz-[TbIII(TD647)]	278	100%	100%	100%	100%	too stable
TD866 B	1,5-cz-[DyIII(TD647)]	278	100%	100%	100%	100%	too stable
TD648 B	1,5-cz-[HoIII(TD647)]	278	100%	100%	100%	100%	too stable
TD865 B	1,5-cz-[ErIII(TD647)]	278	100%	100%	100%	100%	too stable
TD601 B	1,5-cz-[TmIII(TD647)]	278	100%	100%	100%	100%	too stable
TD602 B	1,5-cz-[YbIII(TD647)]	278	100%	100%	100%	100%	too stable
TD522 B	1,5-cz-[LuIII(TD647)]	278	100%	100%	100%	100%	too stable
TD649 B	1,5-cz-[YIII(TD647)]	278	100%	100%	100%	100%	too stable
TD876 A	1,5-cz-[PbII(TD647)]	278	6%	0%	0%	0%	2.4E −1
TD863 A	1,5-cz-[CaII(TD647)]	278	39%	0%	0%	0%	7.3E −1
TD880 A	1,5-cz-[CdII(TD647)]	278	100%	100%	100%	100%	too stable
TD890 A	1,5-cz-[ZnII(TD647)]	278	100%	93%	54%	5%	1.9E 2 ± 8.5E0
TD624-La A, *	[LaIII(p-NO2BnDOTA)]	285	95%	36%	0%	0%	1.6E 1 ± 1.8E−1
TD624-Gd A, *	[GdIII(p-NO2BnDOTA)]	285	100%	99%	92%	79%	2.1E 3 ± 1.2E2
TD624-Lu A, *	[LuIII(p-NO2BnDOTA)]	285	99%	98%	87%	67%	1.2E 3 ± 8.7E1
TD925 B	1,5-cz-[GdIII(TD921)]	275	100%	100%	100%	100%	too stable
Legend:
A Aliquots (2 μL) were diluted with H2O (200 μL) prior measurement.
B Aliquots (2 μL) were neutralized with 500 mM MOPS/NaOH buffer (pH 7.0; 200 μL) prior measurement.
f Dissociation data were fitted by exponential decay (equation y = exp(−x/t); y = fraction of intact chelate; x = time; t = decay constant). Chelate stability is expressed as half-life t1/2 (in hours; highlighted bold), derived from decay constant (t1/2 = ln(2) × t). The error of the fitting is not displayed for single data point fitting.
* Sum of two diastereoisomers.
Stock solutions preparation: In Eppendorf tube (0.5 mL), 2,2′,2″,2″′-(2-(4-nitrobenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid tetrahydrochloride (10.0 mM in H2O; 100 μL; 1 μmol; 1.0 equiv.) was mixed with corresponding aq. LnCl3 (100 mM; 23.5 μ L; 1.1 μmol; 1.1 equiv.), H2O (59 μL) and aq. NaOH (400 mM; 17.5 μL; 7.0 μmol; 7.0 equiv.). The resulting mixtures were then stirred 16 h at RT (full conversion was confirmed by LC-MS) followed by centrifugation. Supernatants were then directly used as stock solutions for the dissociation assay.

CHART 21
Cleavage of model hexapeptide-chelate conjugates into parent chelate and individual amino acids in aq. 3.0M HCl at 80°
C. over the course of 1 week (acid peptide hydrolysis kinetics): fractions of starting chelate-peptide conjugate (S), chelate-
containing intermediates (I), parent chelate (P) and free ligand (L) determined by analytical HPLC (H2O—MeCN system
with 0.1% FA additive; detection at 285 nm; rounded to integers; aliquots from reaction mixtures were neutralized with
MOPS buffer, pH 7.0, vortexed and then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	species	1 h	1 d	2 d	3 d	4 d	5 d	6 d	7 d
TD802 ′	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	48%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	9%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	8%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	21%	12%	2%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig)]	P	7%	88%	98%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD792 ′	1,5-cz-[YIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHVG-OH)]	I	46%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHV-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFH-OH)]	I	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYF-OH)]	I	9%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AY-OH)]	I	9%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-A-OH)]	I	22%	13%	2%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-COOH)]	P	7%	84%	91%	90%	87%	84%	81%	77%
	1,5-cz-Lig #	L	0%	3%	7%	10%	13%	16%	19%	23%
TD902 ″	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	32%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	6%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	13%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig)]	P	39%	100%	100%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD901 ″	1,5-cz-[TmIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHVG-OH)]	I	34%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFH-OH)]	I	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYF-OH)]	I	6%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AY-OH)]	I	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-A-OH)]	I	12%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig)]	P	37%	100%	100%	100%	100%	100%	100%	99%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	1%
Legend:
′ Hexapeptide is connected to the chelate through aromatic amide moiety.
″ Hexapeptide is connected to the chelate through aliphatic amide moiety.
# Sum of 1,5-cz-Lig and 1,5-cz-Lig-A-OH.

CHART 22
Cleavage of model hexapeptide-chelate conjugates into parent chelate and individual amino acids in aq. 2.0M HCl at 80°
C. over the course of 1 week (acid peptide hydrolysis kinetics): fractions of starting chelate-peptide conjugate (S), chelate-
containing intermediates (I), parent chelate (P) and free ligand (L) determined by analytical HPLC (H2O—MeCN system
with 0.1% FA additive; detection at 285 nm; rounded to integers; aliquots from reaction mixtures were neutralized with
MOPS buffer, pH 7.0, vortexed and then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	species	1 h	1 d	2 d	3 d	4 d	5 d	6 d	7 d
TD802 ′	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	65%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	7%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	6%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	13%	30%	8%	3%	1%	0%	0%	0%
	1,5-cz-[LuIII(Lig)]	P	5%	69%	92%	97%	99%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD792 ′	1,5-cz-[YIII(Lig-AYFHVG-NH2)]	S	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHVG-OH)]	I	63%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFH-OH)]	I	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYF-OH)]	I	7%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AY-OH)]	I	6%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-A-OH)]	I	14%	28%	10%	4%	1%	0%	0%	0%
	1,5-cz-[YIII(Lig-COOH)]	P	5%	70%	88%	93%	94%	94%	93%	92%
	1,5-cz-Lig #	L	0%	1%	2%	4%	5%	6%	7%	8%
TD902 ″	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	48%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	9%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig)]	P	31%	100%	100%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD901 ″	1,5-cz-[TmIII(Lig-AYFHVG-NH2)]	S	0%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHVG-OH)]	I	50%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFH-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYF-OH)]	I	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AY-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-A-OH)]	I	8%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig)]	P	30%	100%	100%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
Legend:
′ Hexapeptide is connected to the chelate through aromatic amide moiety.
″ Hexapeptide is connected to the chelate through aliphatic amide moiety.
# Sum of 1,5-cz-Lig and 1,5-cz-Lig-A-OH.

CHART 23
Cleavage of model hexapeptide-chelate conjugates into parent chelate and individual amino acids in aq. 1.0M HCl at 80°
C. over the course of 1 week (acid peptide hydrolysis kinetics): fractions of starting chelate-peptide conjugate (S), chelate-
containing intermediates (I), parent chelate (P) and free ligand (L) determined by analytical HPLC (H2O—MeCN system
with 0.1% FA additive; detection at 285 nm; rounded to integers; aliquots from reaction mixtures were neutralized with
MOPS buffer, pH 7.0, vortexed and then injected to HPLC). Performed in glass vials with magnetic stirrers.
chelate	species	1 h	1 d	2 d	3 d	4 d	5 d	6 d	7 d
TD802 ′	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	4%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	80%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	2%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	3%	2%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	3%	5%	1%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	6%	55%	40%	28%	17%	10%	6%	3%
	1,5-cz-[LuIII(Lig)]	P	2%	34%	59%	72%	83%	90%	94%	97%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD792 ′	1,5-cz-[YIII(Lig-AYFHVG-NH2)]	S	5%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHVG-OH)]	I	77%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYFH-OH)]	I	2%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AYF-OH)]	I	4%	2%	0%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-AY-OH)]	I	3%	5%	1%	0%	0%	0%	0%	0%
	1,5-cz-[YIII(Lig-A-OH)]	I	6%	56%	35%	26%	16%	8%	5%	4%
	1,5-cz-[YIII(Lig-COOH)]	P	2%	35%	64%	73%	83%	91%	93%	95%
	1,5-cz-Lig #	L	0%	0%	0%	1%	1%	1%	2%	2%
TD902 ″	1,5-cz-[LuIII(Lig-AYFHVG-NH2)]	S	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHVG-OH)]	I	67%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYFH-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AYF-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-AY-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig-A-OH)]	I	4%	3%	0%	0%	0%	0%	0%	0%
	1,5-cz-[LuIII(Lig)]	P	19%	97%	100%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
TD901 ″	1,5-cz-[TmIII(Lig-AYFHVG-NH2)]	S	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHVG-OH)]	I	68%	1%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFHV-OH)]	I	1%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYFH-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AYF-OH)]	I	3%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-AY-OH)]	I	2%	0%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig-A-OH)]	I	4%	4%	0%	0%	0%	0%	0%	0%
	1,5-cz-[TmIII(Lig)]	P	19%	95%	100%	100%	100%	100%	100%	100%
	1,5-cz-Lig	L	0%	0%	0%	0%	0%	0%	0%	0%
Legend:
′ Hexapeptide is connected to the chelate through aromatic amide moiety.
″ Hexapeptide is connected to the chelate through aliphatic amide moiety.
# Sum of 1,5-cz-Lig and 1,5-cz-Lig-A-OH.

CHART 24
Cell penetrating properties of TD975, TD989, TD1010 and TD1011 (CPP-conjugates). Protocol: Grown cells (CCRF-CEM;
T-lymphoblastic leukemia) were centrifuged (250 × g, RT), washed with PBS and resuspended in RPMI medium Dutch modification
(with HEPES buffer, without antibiotics) to a concentration 2.5 × 107 mL−1. Suspension was transferred
into 12 (4 CPP-conjugate combinations, each in triplicate) Eppendorf tubes (400 μL of suspension to each).
Stock solution of CPP conjugates (5.0 mM, 50 μL) were added to reach 0.5 mM final concentration of given CPP-conjugate.
Cells were then incubated 2 h at 37° C. After incubation, samples were centrifuged (900 × g, RT). Medium
was carefully pipetted out and the pellets twice washed with 1 mL PBS. Resulting pellets were treated with HCl
(3.0M, 500 μL) and stirred 7 days at 80° C. Resulting solutions were then analyzed for cell uptake.
CPP conjugates incubated with cells	cell uptake, %
0.5 mM TD975 + 0.5 mM TD989	TD975 a	0.54 ± 0.012% b	0.57 ± 0.039 c	TD989 a	0.47 ± 0.049 b	0.47 ± 0.052 c
0.5 mM TD1011 + 0.5 mM TD1010	TD1011a	0.13 ± 0.013% b	0.15 ± 0.017 c	TD1010a	0.13 ± 0.003 b	0.14 ± 0.019 c
0.5 mM TD975 + 0.5 mM TD1010	TD975 a	0.72 ± 0.006% b	0.73 ± 0.020 c	TD1010a	0.06 ± 0.036 b	0.06 ± 0.027 c
0.5 mM TD1011 + 0.5 mM TD989	TD1011 a	0.07 ± 0.014% b	0.07 ± 0.049 c	TD989 a	0.69 ± 0.003 b	0.66 ± 0.018 c
Legend:
a analysed as TD748 and TD897 after acid hydrolysis of parent CPP conjugates.
b quantified by LC-MS: UV integration at 285 nm; ESI-MS integration of EIC+ 841-843 m/z ([TD748]+) and 835-837 m/z ([TD897]+). The quantification was based on calibration (of both UV and ESI-MS modes) using stock solutions of TD748 and TD897 with known concentrations.
c quantified by ICP.

Abbreviations and Definitions

• • cyclene 1,4,7,10-tetraazacyclododecane
  • Cbz benzylchloroformate
  • ^tBu terc-butyl
  • Boc benzyloxycarbonyl
  • DCM dichloromethane
  • TFA trifluoroacetic acid
  • TIPS triisopropylsilyl
  • TMS trimethylsilyl
  • Ph phenyl
  • Fmoc fluorenylmethyloxykarbonyl
  • iPr isopropyl
  • MOPS 3-(N-morpholino)propanesulfonic acid
  • DIPEA N,N-Diisopropylethylamine
  • LC-MS liquid chromatography-mass spectrometry
  • MRI magnetic resonance imaging
  • aryl substituent derived from at least one aromatic hydrocarbon ring by removal of one hydrogen atom from the aromatic ring, e.g. phenyl or naphtyl
  • alkyl substituent derived from an alkane (linear or branched) which is derived from an alkane by removal of one hydrogen atom, e.g. methyl or ethyl
  • arylalkyl substituent derived from an aryl-substituted alkane (linear or branched) which is derived from an alkane by removal of one hydrogen atom from the alkane chain., e.g. benzyl
  • arylalkynyl substituent derived from an aryl-substituted alkyne by removing one hydrogen (thus containing a triple bond), which may be linear or branched
  • click-zip closed cage ligand or complex, wherein the click reaction between the azide and the triple bond took place and the triazole bridge was formed, thereby “zipping” the metal coordination place.
  • 1,5-cz-[M(Lig)] from Lig and M ions is a general notation of the coordination compounds according to the present invention. “1,5-cz-” stands for a 1,5-triazole bridged cage, [M(Lig)] stands for a coordination compound of a metal cation and a ligand (the compound according to general formula (I)).

Claims

1. A compound of general formula (I)

2. The compound of general formula (I) according to claim 1, wherein:Y is nitrogen;R1 is selected from the group consisting of H; Cl; —N(CH3)2; phenyl, which can optionally be substituted with —COOH or —CH2COOH; benzyl, which can optionally be substituted with —COOH or —CH2COOH; —CF3; —COOCH3; —COOCH(CH3)2; —COOtBu;

3. The compound according to claim 1, wherein Z is

4. The compound of general formula (I) according to claim 1, wherein R2 and R3 together form a 1,2,3-triazole group of formula

5. The compound of general formula (I) according claim 1, selected from the group comprising compounds, wherein Y is nitrogen, Z is

6. A method of preparation of the compound of the general formula (I) according to claim 1, comprising the following steps: i) providing an alkyne intermediate of general formula Z—Cl, wherein Z as defined in claim 1;ii) providing an azide intermediate of general formula (III)

7. A coordination compound of the compound of the general formula (I) according to claim 1 with a metal cation, selected from the group consisting of lanthanide(III) cations, Na+, Ba2+, Pb2+, Sr2+, Ca2+, Cd2+, Zn2+, Mn2+, Pt2+, Cu2+, Ni2+, Sc3+, Y3+, Bi3+, In3+, Ru3+, Ir3+, Ga3+, Tl3+, Pd2+; preferably the metal cation is selected from the group consisting of La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Tl3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+, Y3+, Sc3+, Bi3+, In3+, Tl3+, Pb2+, Ca2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Pd2+, Na+.

8. A method of preparation of the coordination compound according to claim 7, comprising the following steps: i) synthesis of the compound of the general formula (I) according to claim 6;ii) providing a salt of an inorganic acid and a metal cation, selected from the group consisting of lanthanide(III) cations, Na+, Ba2+, Pb2+, Sr2+, Ca2+, Cd2+, Zn2+, Mn2+, Pt2+, Cu2+, Ni2+, Sc3+, Y3+, Bi3+, In3+, Ru3+, Ir3+, Ga3+, Tl3+, Pd2+; wherein the salt is selected from a group comprising chloride, nitrate, acetate, formate, trifluoroacetate, trifluoromethylsulfonate;iii) mixing the compound of the general formula (I) from step i) with the metal salt from step ii) in aqueous solution, preferably for at least 1 hour at temperature in the range of from 25 to 100° C., resulting in chelation of the metal cation by the compound of general formula (I) and formation of the coordination compound according to claim 7;iv) transformation of the coordination compound from step iii), wherein the transformation is selected from at least one of the following reactions:substitution reaction of halogen group present in R1 and/or R4 and/or R5, with a phenylboronic acid, thus transforming the halogen substituent into —COOH;substitution reaction of halogen group present in R1 and/or R4 and/or R5, with —N3 group by reaction with NaN3;hydrolysis of TIPS protecting group present in R1 and/or R4 and/or R substituent, wherein R1 and/or R3 and/or R5 is

9. A coordination compound chain containing at least two coordination compounds according to claim 7, bound via a triazole bridge formed between R1 or R5 group of the first coordination compound and R1 or R5 group of the following coordination compound and/or via amide bond formed between a substituent R1 or R4 or R5 or A of one coordination compound containing an amine group and a substituent R1 or R4 or R5 or A of another coordination compound containing a carboxyl group and/or via disulfide bonds formed between a substituent R1 or R5 of one coordination compound containing —SH group, and a substituent R1 or R5 of another coordination compound containing —SH group.

10. A coordination compound dimer of general formula (X)

11. A conjugate for drug tracing, which contains the coordination compound according to claim 7, conjugated to a peptide or to a protein; wherein the coordination compound according to claim 7 contain R1 and/or R4 and/or R5 group comprising —NH2 or —COOH group; preferably R1 and/or R4 and/or R5 is selected from —NH2; —(CH2)nNH2; —COOH; —(CH2)nCOOH; C6 to C10 aryl, substituted with —NH2, —COOH, —(CH2)nNH2, or —(CH2)nCOOH; wherein n is an integer in the range of from 1 to 3; which is conjugated to the peptide or the protein via an amide bond formed between —COOH group present in R1 and/or R4 and/or R5 and amino group of the peptide or the protein or via an amide bond formed between—NH2 group present in R1 and/or R4 and/or R5 and carboxyl group of the peptide or the protein;and wherein the peptide is selected from the group comprising oligopeptides of 3 to 20 aminoacids;and wherein the protein is selected from the group comprising antibodies, preferably monoclonal antibodies.

12. A method of drug tracing, comprising the following steps: i) providing a cell culture or a tissue to be analyzed, containing at least one conjugate according to claim 11, wherein the peptide or the protein is of the peptide-based or protein-based drug to be traced;ii) hydrolyzing the cell culture or tissue from step i) using a strong acid, preferably HCl, obtaining a hydrolyzate;iii) qualitative and/or quantitative analysis of the hydrolyzate of step ii) for the presence of the coordination compound, preferably using LC-MS.

13. The coordination compound according to claim 7 for development and testing of new drugs for drug marking and tracing in vitro.

14. The coordination compound according to claim 7 for medical diagnostics as MRI contrast agents.

15. The coordination compound according to claim 7 wherein M is selected from the group comprising 44Sc, 47Sc, 64Cu, 67Cu, 86Y, 90Y, 140Nd, 149Pm, 151Pm, 153Sm, 159Gd, 149Tb, 161Tb, 165Dy, 161Ho, 166Ho, 169Er, 167Tm, 175Yb, 177Lu, and/or R1, R4 and/or R5 contains a radioactive halogen as radiodiagnostic and/or radiopharmaceutic agents.