Patent Application
20140142298
This invention relates in certain embodiments to a new synthesis method for the 1,4,7 triazacyclononane (tacn) precursor and its N- and/or C-functionalized derivatives. The method according to these and related embodiments comprises the preparation of imadazo[1,2-a]pyrazin4-ium salts that can be used for synthesis of tacn and its N- and/or C-functionalized derivatives. Also provided in certain embodiments are new N- and/or C-functionalized macrocyclic molecules derived from tacn and the imadazo[1,2-a]pyrazin-4-ium salts.
Polyazamacrocycles and their derivatives are nitrogen-containing macrocycles known for their sequestration properties of transition metals and heavy metals. They have applications in a wide variety of fields including treatment of liquids, catalysis or health and more particularly medical imaging.
Among these macrocyclic systems, derivatives of the tridentate 1,4,7 triazacyclononane (tacn) ligand, macrocycle carrying three nitrogen atoms, possess very good complexing properties, making them likely to be useful for many applications. In particular, the capacity of nitrogen-containing derivatives of tacn to stabilise metal ions with a high oxidation state and particularly Manganese ions (Mn (IV)) explains their use in many catalytic processes, as in olefin polymerisation reactions or olefin epoxidation reactions with hydrogen peroxide in water (Sibbons et al., Dalton Trans. 2006, 645-661). In this context, the trimethyl-tacn (metacn) system has been especially studied for its catalytic activity in the form of dinuclear complexes of manganese. Complexes of tacn-Mn(IV) have also been suggested as bleaching agents, particularly in detergents, to replace some oxidants (WO01/64826). Tacn derivatives have also been disclosed as cosmetic agents for hair perm, or as keratin extracting agents (FR2862 217, WO2005/049870).
The interest in tacn derivatives has been continuously growing during the last approximately ten years, particularly due to the advantages of this type of system for sequestration of radiometals for applications in SPECT (Single Photon Emission Computed Tomography) and PET (Positron Emission Tomography) nuclear imaging. These macrocyclic molecules are then used as a bifunctional chelating agent capable firstly of sequestering the radioactive source (In, Ga, Cu, Y, etc.) and also of coupling with a vector biomolecule. This indirect labeling method is now a preferred method for medical imaging and for radioimmunotherapy.
NOTA is one tacn derivative frequently used in imaging, and corresponds to the tacn possessing three methylcarboxylate functions on nitrogen atoms. Different physicochemical and structural studies have been done on NOTA complexes intended for SPECT/PET imaging or therapy and in particular have demonstrated that the 64Cu-NOTA and 67/68Ga-NOTA metallic complexes have good in vivo stability. The radiolabeling rate is also relatively fast, requiring mild radiometallation conditions compatible with labeling of antibody type biological molecules (see for example US2012/064003, WO2009/079024, US2011/0070157).
In order to improve existing systems, efforts have been concentrated on optimization of their properties, particularly by developing C-functionalized macrocycles. C-functionalization is an approach that consists of introducing a “grafting” function onto the carbon skeleton of the macrocycle. The C-functionalization of tacn may optionally be accompanied by the addition of chelating arms on the three nitrogen atoms of the cycle. This approach has been applied for the synthesis of new bifunctional chelating agents. However it is relatively limited, because of the difficulty to synthesize C-functionalized macrocycles.
Access to such “bifunctional chelating” systems requires firstly an efficient method of synthesizing the “basic” macrocycle, in this case the tacn motif, and secondly the ability to selectively functionalize this motif at the nitrogen atoms (N-functionalization) and/or in the carbon skeleton (C-functionalization).
To the knowledge of the Applicant, at the present time only one synthesis method is used for the synthesis of 1,4,7-triazacyclononane (tacn) and its N-functionalized analogues, known under the term “Richman-Atkins cyclization” (Richmans, J. E., Atkins, T. J. J. Am. Chem. Soc. 1974, 96, 2268-2270). The method for synthesising tacn described by Richman and Atkins is summarised in the scheme 1 below:
This synthesis method has many disadvantages, particularly the use of tosyl groups during the cyclization step, long reaction times and a global yield of not more than 12%. Drastic conditions for the elimination of tosyl groups (H2SO4, 100° C. for 2 days) form a major obstacle for transposing this method to a large scale, without considering the problem that this synthesis method is not atom-economic.
“Richman-Atkins” cyclization conditions were used for the preparation of C-functionalized derivatives starting from diols or linear amines functionalized on one of the carbon atoms (Argouarch et al., Tetrahedron Lett. 2002, 43, 3795-3798; Argouarch et al., Org. Biomol. Chem. 2003, 1, 2357-2363; Stones et al., Org. Biomol. Chem. 2003, 1, 4408-4417; Scheuermann et al., Org. Biomol. Chem. 2004, 2, 2664-2670; Mc Murry et al., Bioconjugate Chem., 1993, 4, 236-245).
Since the function cannot be introduced into the carbon skeleton by simple C-C coupling, these syntheses make use of biselectrophilic synthons possessing the desired function. This synthesis method is directly inspired from Richman and Atkins' method of obtaining tacn and requires drastic deprotection conditions that considerably limit the nature of functional groups that may be introduced into the macrocycle.
A synthesis method providing access to C-functionalized derivatives was recently described by J. M. Kohlen's team (Koek J. and Kohlen E., Tetrahedron Lett. 2006, 47, 3673-3675). In this method, N-methylated tacn (metacn) is oxidized by N-bromosuccinimide (NBS) to lead to the corresponding bicyclic iminium. The addition of potassium cyanide allows the opening of the bicyclic structure and the formation of a nine-member ring. Reduction of the nitrile group can form an amine function allowing the possibility of further functionalization.
However, this synthesis method requires the preliminary synthesis of metacn by Richman-Atkins cyclization. This method is also very limited because it only provides access to C-functionalized derivatives of metacn. Indeed, methyl groups cannot be removed and therefore, this approach cannot be used for preparation of tacn derivatives possessing coordinating groups on nitrogen atoms (carboxylates, phosphonates, etc.) useful for applications in medical imaging.
Thus, despite the strong potential of C-functionalized tacn systems, very few molecules of this type have been described so far, mainly due to difficulties with synthesis.
Therefore, according to certain embodiments of this invention there is disclosed a new method of synthesis of the 1,4,7-triazacyclononane precursor (tacn) and its N- and/or C-functionalized derivatives. The method according to these and related embodiments comprises the synthesis of imidazo[1,2-a]pyrazin-4-ium salts. Also provided according to certain herein disclosed embodiments are new macrocyclic molecules derived from tacn and imidazo[1,2-a]pyrazin-4-ium salts.
In this disclosure, the following definitions of terms are applicable:
When groups may be substituted, they may be substituted by one or several substituents, preferably one, two or three substituents. Substituents may for example be selected from the group comprising halo, hydroxyl, oxo, nitro, amido, carboxy, amino, cyano, haloalkoxy, haloalkyl.
Certain embodiments of this invention apply to a method for the synthesis of triazacyclononane (tacn) and derivatives of N- and/or C-functionalized tacn, these compounds corresponding to the general formula (I″)
and its salts wherein
Ra, Rb and Rc may be identical or different and each represents
a hydrogen atom, or
R represents a hydrogen atom or a group A;
A represents
When A represents a (CH2)w2—NA″A′″ wherein at least either A″ or A′″ represents a —C(═O)—Z group wherein Z represents an organic fluorescent motif, the fluorescent motif is preferably coupled with the macrocyclic unit by peptidic coupling, possibly but not necessarily through an amino acid spacer. According to one preferred embodiment, the fluorescent motif is more particularly a boron dipyrromethene type motif (Bodipy®) preferably comprising a COOH or NH2 type binding functional group.
C-functionalized tacn derivatives and C- and N-functionalized tacn derivatives are more specifically represented by the general formula (I); while tacn and its N-functionalized derivatives are represented more specifically by the general formula (I′):
and their salts, wherein Ra, Rb, Rc and A are as defined in the general formula (I″).
Formula (I) corresponds to the general formula (I″) wherein R is an A group. Formula (I′) corresponds to the general formula (I″) wherein R is a hydrogen atom.
The method for preparation of compounds with formula (I″) includes the steps shown in scheme 3:
In particular, steps (c) and (d) leading from compound (V) to compound (I″) are as follows (Scheme 4), the steps shown in dashed lines being optional:
Compounds (Ia) and (I′ a) are special cases of formulas (I) and (I′) respectively, that themselves form special cases of the general formula (I″) as mentioned above.
Steps (c), (c′), (d) and (d′) make use of chemical modifications known to those skilled in the art. The essential point is that there is an efficient and versatile method of preparing the compound with formula (V).
Consequently, this invention relates in certain embodiments to a method for preparation of a compound with formula (V)
wherein
X represents a radical selected from bromo, iodo or chloro radicals;
R1 represents a (CH2)p—B radical wherein
According to one embodiment, the invention relates to a method for preparation of a compound with formula (V′)
According to one embodiment, the invention relates to a method for preparation of a compound with formula (I″)
or its salts, wherein R1′″, R2′″ and R3′″ represent R1, R2 and R3 as defined above respectively, or their derivatives formed by reaction with the reducing agent used in step (d);
According to a first particular embodiment, the method according to the invention includes the formation of the compound with formula (V-Bn) as a result of steps (a) and (b) described above, corresponding to the compound (V) wherein R1, R2 and R3 are identical and represent an unsubstituted benzyl,
According to one embodiment, when the method according to the invention leads to the compound with formula (I′ a-Bn), the method may also comprise a catalytic hydrogenation step (d′ 1) then leading to the compound (tacn) corresponding to formula (I′) wherein Ra, Rb and Rc are identical and represent a hydrogen atom:
Thus, according to one embodiment of the invention, the synthesis of tacn comprises the steps shown in the following diagram:
In one embodiment, the method according to the invention leads to the compound (tacn) and also comprises at least one subsequent additional step (d′2) leading to functionalization of three atoms of macrocycle nitrogen, using a method known to those skilled in the art (for example see J. P. L. Cox et al. J. Chem. Soc., Perkin Trans. 1990, 2567-2576, A. N. Singh et al., Bioconjugate Chem., 2011, 22, 1650-1662, P. J. Riss et al., Bioorg. Med. Chem. Lett., 2008, 18, 5364-5367, J. Simecek et al., Inorg. Chem. 2012, 51, 577-590, Lukes et al, Chem. Eur. J, 2010, 16, 714-7185).
According to a second particular embodiment, the method according to the invention leads to the formation of a compound with formula (Ia-i), as a result of steps (a), (b) and (c):
or its salts, wherein D represents a hydrogen atom or a radical selected from cyano, nitro, amino radicals, halo (preferably bromo or iodo), alkoxy, (preferably methoxy), hydroxy radicals, and E represents a CH group or a nitrogen atom.
According to one embodiment, when the method according to the invention leads to the compound with formula (Ia-i), the method may also comprise a reduction step (c′ 1), preferably by aluminium and lithium tetrahydride, then leading to the compound with formula (I-i):
or its salts, wherein D and E are as defined above.
According to one embodiment, when the method according to the invention leads to the compound with formula (I-i), the method may also comprise a subsequent additional step (c′2) during which the NH2 group of (I-i) is functionalized according to an appropriate treatment known to those skilled in the art, for example such as N-alkylation or N-arylation by nucleophilic substitution reactions, a nucleophilic addition or a reducing amination of aldehydes, to form the compound with formula (I-ii):
or its salts, wherein D, E, A″ and A′″ are as defined above.
According to one particular embodiment, when the method according to the invention leads to the compound with formula (I-i) or the compound (I-ii) wherein D is a hydrogen atom and E is a CH group, the method may also comprise a subsequent additional catalytic hydrogenation step (c′3), leading the compound with formula (I-iii):
or its salts, wherein A″ and A′″ are as defined above.
According to one particular embodiment, when the method according to the invention leads to the compound with formula (I-iii), the method may also comprise a subsequent additional step (c′4) leading to the functionalization of three nitrogen atoms of the macrocycle by the introduction of Ra, Rb and Rc groups as defined previously, by a method known to those skilled in the art (for example see J. P. L. Cox et al. J. Chem. Soc., Perkin Trans. 1, 1190, 2567-2576, A. N. Singh et al., Bioconjugate Chem., 2011, 22, 1650-1662, P. J. Riss et al., Bioorg. Med. Chem. Lett., 2008, 18, 5364-5367, J. Simecek et al., Inorg. Chem. 2012, 51, 577-590, J. M. Jeong et al., J. Nucl. Med. 2008, 49, 830-836), leading to the compound with general formula (I-iv)
or its salts, wherein Ra, Rb, Rc, A″ and A′″ are as defined above.
According to one particular embodiment, the method according to the invention leads to the compound (I-iv) wherein Ra, Rb and Rc are identical and preferably represent:
As illustrated in the following examples, the method according to certain embodiments of the invention can be used for direct synthesis of N- and/or C-functionalized triazacyclononanes that represent high added value macrocycles. Target systems are obtained in few steps, starting from commercially available compounds. Unlike syntheses described in prior art, none of the steps in the method according to certain of the present invention embodiments require any special conditions such as high dilution conditions, use of prolonged treatment in concentrated acid medium, or work under inert atmosphere. Therefore the method according to certain embodiments can be used at large scale.
The mild conditions for the method according to the presently disclosed embodiments enable the introduction of a very wide variety of organic functions, unlike methods that make use of tosyl groups. Therefore new C-functionalized agents based on triazacyclononane could be prepared using the method according to certain embodiments.
This invention relates in certain embodiments to new macrocyclic compounds derived from 1,4,7-triazacyclononane (tacn) carrying a functional group at a carbon atom of the macrocycle, denoted under the name of “C-functionalized tacn derivatives”.
According to one embodiment, the C-functionalized tacn derivatives according to this invention have the general formula (I)
and its salts, wherein
Ra, Rb and Rc may be identical or different and each represents
A represents
According to one embodiment, the compounds with general formula (I) are as defined above, with the condition that:
In a specific embodiment, A′ does not represent a saturated or unsaturated, branched or unbranched, substituted or unsubstituted aliphatic group comprising 1 to 12 carbon atoms.
In a specific embodiment, A is not a benzyl group substituted in para position by a thiourea derivative.
According to one particular embodiment, A is not a benzyl or an alkyl group comprising 1 to 8 carbon atoms. According to one particular embodiment, when Ra, Rb and Rc are identical or different and represent —(CH2)n—R′ wherein R′ represents an aliphatic group, a substituted or unsubstituted benzyl group, a substituted or unsubstituted methylpyridine group, —(CH2)2—OR′1, then A is not a benzyl or an alkyl group comprising 1 to 8 carbon atoms.
According to one particular embodiment, when compounds with general formula (I) are salts and Ra, Rb and Rc are identical or different and represent a hydrogen atom or a substituted or unsubstituted alkyl group, then A is not a substituted or unsubstituted alkyl group.
According to one embodiment, compounds with general formula (I) are salts and in this case the counter ion is preferably derived from Cl, Br, I, TFA (trifluoroacetic acid).
According to one embodiment, compounds with general formula (I) may be obtained by the method according to this invention.
Compounds with formula (I) according to certain herein disclosed invention embodiments are composed of a cyclic core comprising three nitrogen atoms connected in pairs by an ethylene motif and a functional group A carried by the carbon skeleton. The three nitrogen atoms may be substituted or unsubstituted by groups Ra, Rb and Rc. According to one particular embodiment, Ra, Rb and Rc are coordinating groups that can complete the coordination sphere when a metallic ion is incorporated.
Compounds according to certain embodiments have the advantages of C-functionalization of nitrogen-containing macrocycle ligands, namely they offer the possibility of introducing a new functionality on the macrocyclic molecule while maintaining the three groups Ra, Rb and Rc to complete the coordination sphere of the metal that can be complexed.
According to one embodiment, the compounds according to the invention have the general formula (Ia):
and its salts, wherein
R1 represents a (CH2)p—B radical wherein
Nu represents a carbonated nucleophilic group, Nu for example represents CN, an alkyl group, an aryl group or a malonate group.
According to one embodiment, compounds according to the invention have a general formula (Ib):
and its salts, wherein A is as defined in formula (I).
According to one embodiment, the preferred compounds with formula (Ib) are compounds wherein A represents a —(CH2)w2—NA″A″ group wherein w2, A″ and A′ are as defined above; A preferably represents a —(CH2)—NA″A′″ group and in this case has a specific formula (I-iii).
According to one embodiment, the compounds according to the invention have the general formula (Ic):
and its salts, wherein A, n and R′ are as defined in formula (I).
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 1 and R′ represents a —C(═O)—OR′1 group wherein R′1 represents a hydrogen atom or a saturated or unsaturated, branched or unbranched, substituted or unsubstituted aliphatic group comprising 1 to 12 carbon atoms, preferably R′1 represents a hydrogen atom or a methyl, ethyl or tert-butyl group.
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 1 and R′ represents a —P(═O)—R′2R′3 group wherein R′2 and R′3 may be identical or different and each represents a —(CH2)m1—R″1 group wherein m1 is as defined above and R″1 represents a saturated or unsaturated aliphatic chain, possibly interrupted by one or several oxygen, nitrogen or sulphur atoms; R″1 preferably represents a methyl, ethyl, methoxy, ethoxy group; R′1 preferably represents P(═O)-Me(OEt).
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 0 and R′ represents an unsubstituted benzyl group or a benzyl group substituted in the meso and/or meta and/or para and/or ortho position by one or several radicals selected from cyano, nitro, amino, halo (preferably bromo, iodo or fluoro), alkoxy (preferably methoxy), hydroxy radicals; R′ preferably represents an unsubstituted benzyl group.
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 0 and R′ represents an unsubstituted methylpyridine group or a methylpyridine group substituted par one or several groups selected from cyano, nitro, amino, halo (preferably bromo or iodo), alkoxy (preferably methoxy), hydroxy groups; R′ preferably represents an unsubstituted methylpyridine group.
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 0, R′ represents a benzyl group or a methylpyridine group, said groups being unsubstituted or substituted by one or several groups selected from cyano, nitro, amino, halo (preferably bromo or iodo) alkoxy (preferably methoxy) groups, and A represents a —(CH2)NH2 group represented by the specific formula (I-i).
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 0, R′ represents a benzyl group or a methylpyridine group, said groups being unsubstituted or substituted by one or several groups selected from cyano, nitro, amino, halo (preferably bromo or iodo) alkoxy (preferably methoxy) groups, and A represents a —(CH2)NA″A′″ group wherein A″ and A′″ are as defined above, represented by the specific formula (I-ii).
According to one embodiment, preferred compounds with formula (Ic) are compounds wherein n is equal to 0, R′ represents an unsubstituted benzyl or methylpyridine group, substituted by one or several groups selected from cyano, nitro, amino, halo (preferably bromo or iodo), alkoxy (preferably methoxy) groups, and A represents a cyano group, represented by the specific formula (Ia-i).
According to one embodiment, compounds according to the invention have the general formula (Id):
and its salts, wherein Ra, Rb, Rc, w1 and A′ are as defined in formula (I).
According to one embodiment, preferred compounds with formula (Id) are compounds wherein w1 is equal to 0 and A′ represents a cyano group.
According to one embodiment, preferred compounds with formula (Id) are compounds wherein w1 is equal to 0, A′ represents a cyano group and Ra, Rb and Rc are identical and represent —(CH2)n—R′ group wherein n is preferably equal to 0 and R′ represents an unsubstituted benzyl group or a benzyl group substituted in the meso and/or meta and/or para and/or ortho position by one or several radicals selected from cyano, nitro, amino, halo (preferably bromo, iodo or fluoro), alkoxy (preferably methoxy), hydroxy radicals; more preferably R′ represents an unsubstituted benzyl group.
According to one embodiment, the compounds according to the invention have the general formula (Ie):
and its salts, wherein Ra, Rb, Rc, w2, A″ and A′″ are as defined in formula (I).
According to one embodiment, preferred compounds with formula (Id) are compounds wherein w2 is equal to 1, represented by the specific formula (I-iv).
According to one embodiment, preferred compounds with formula (Id) are compounds wherein w2 is equal to 1 and A″ represents a hydrogen atom and A′″ represents a —C(═O)—Z group wherein Z represents an organic fluorescent motif, for example such as fluorescein, rhodamine, polymethine, boron dipyrromethene, porphyrine, phthalocyanine, squaraine or a derivative of these groups; preferably Z represents a boron dipyrromethene group.
According to one particular embodiment, compounds (I) according to the invention are such that Ra, Rb and Rc are identical and represent CH2COOH, CH2COOtBu, CH2COOEt, CH2P(═O)(Me)OH or CH2P(═O)(Me)OEt type groups and A is a —CH2NH2 function. The possibly activated —CH2NH2 function can be used to couple the macrocycle to a solid support or a biological support, making use of chemical reactions known to those skilled in the art, for example such as an N-alkylation or N-arylation by nucleophilic substitution reactions, a nucleophilic addition or a reducing amination of aldehydes. Especially, the —CH2NH2 function, not modified, or modified with a suitable functional group, can react with NH2, SH, COOH, OH, azide, alkyne functions or other reactive functions present on the solid or biological support to be functionalized. By “suitable functional group”, it is referred to reactive functions such as for example activated esters, maleimide, azide, alkyne, vinylsulfone or thioctic acid. “Biological support” means entire antibody type biological molecules, fragments of antibodies, peptides, oligonucleotides, aptamers or recombining proteins. According to one particular embodiment, the biological molecule is not folate or a derivative of folate.
“Solid support” means silica gel or an organic polymer. Labeling of nanoparticles is also possible. The possibly activated —CH2NH2 function can also be used to couple the macrocycle to another macrocycle, bismacrocycle, fluorescent dye, or organometallic complex, using chemical reactions known to those skilled in the art, such as for example an N-alkylation or N-arylation by nucleophilic substitution reactions, a nucleophilic addition or a reducing amination of aldehydes.
In one embodiment, one or more biological supports, as defined above, are linked to the macrocycle of the present invention. In a specific embodiment, one, two or more peptides are linked to a macrocycle according to the invention.
In an embodiment, the invention relates to compounds with general formula (I) coupled to a solid support such as for example silica gel, organic polymer, nanoparticle; or to a biological support such as for example entire antibody type biological molecules, fragments of antibodies, peptides, oligonucleotides, aptamers or recombining proteins.
In one particular embodiment, the following compounds comply with formula (I) according to the invention:
In another aspect, the invention also relates in certain embodiments to macrocyclic metallic complexes deriving from compounds with formula (I). According to one embodiment, the metallic complex according to the invention comprises a ligand with formula (I) as disclosed herein, and a metal, preferably in the form of a bi-, tri or tetravalent ion, chosen from the group comprising Zn, Ca, Be, Mg, Sr, Cu, Ba, Cd, Cr, Mn, Fe, Co, Ni, Al, Ga, In, Zr, Tc, Gd, Y, Lu, At, Pb, Sc, Tb, Eu, Yb, Ru, Rh, other lanthanides or one of their radioactive isotopes. Examples of radioactive isotopes are 67Ga, 68Ga, 64Cu, 67Cu, 90Y, 111In, 89Zr, 99mTc, 177Lu, 211At, 212Pb. According to one embodiment, the complexed metal is preferably an ion derived from the Al, In, Ga, Zr and Cu metals. According to one embodiment, the complexed metal in the macrocyclic cavity is preferably a bi, tri or tetravalent ion such as for example the Zn2+, Ca2+, Be2+, Mg2+, Sr2+, Cu2+, Ba2+, Cd2+, Cr2+, Mn2+, Fe2+, Co2+, Ni2+, Al3+, Ga3+, In3+, In3+, Cr3+, Mn3+, Fe3+, Zr4+ ions.
When the macrocyclic metallic complex derived from compounds with formula (I) is used for PET imaging, the complexed metal is preferably 68Ga, 64Cu, 21Sc or 89Zr, 152Tb, 44Sc. The metal may also be A1 to enable labeling with 18F for PET imaging.
When the macrocyclic metallic complex derived from compounds with formula (I) is used for the SPECT imaging, the complexed metal is preferably 111In, 99mTc or 67Ga, 155Tb.
When the macrocyclic metallic complex derived from compounds with formula (I) is used for radiotherapy, preferably radioimmunotherapy, the complexed metal is preferably 90Y, 177Lu, 211At, 212Pb, 21Sc or 64/67Cu.
When the macrocyclic metallic complex derived from compounds with formula (I) is used for MRI, the complexed metal is preferably Gd or Mn.
When the macrocyclic metallic complex derived from compounds with formula (I) is used for fluorescence imaging or PARACEST MRI, the complexed metal is preferably a lanthanide, and even more preferably Tb, Eu or Yb.
The invention also relates in certain embodiments to compounds with formula (V′)
X represents a radical selected from bromo, iodo or chloro radicals;
Ra, Rb and Rc may be identical or different and each represents
According to one embodiment, the compounds with formula (V′) are as defined above, with the condition that Ra, Rb and Rc are not simultaneously three methyl groups.
In one preferred embodiment, Ra and Rc represent (C═O)OtBu type groups and Rb an alkyl or benzyl type group. This embodiment in particular can access systems selectively N-functionalized by successive reactions available to those skilled in the art.
As mentioned previously, the (I″) compounds and particularly the compounds with formula (I) according to certain embodiments of the present invention can act as ligands to form a metallic complex.
According to one embodiment, compounds with formula (I″), and particularly formula (I) may be used as chelating agents for the treatment of liquids, particularly to eliminate traces of metallic elements. In particular embodiments, compounds with formula (I″) may be used for decontamination of radioactive effluents and elimination of toxic heavy metals.
According to one embodiment, compounds with formula (I″), particularly formula (I) may be used for the production of new coordination polymers of the MOF (“Metal-Organic Framework”) type that selectively trap specific gases. These three-dimensional systems may be prepared by self-assembly of polycarboxylic molecular bricks with formula (I″).
According to one embodiment, metallic complexes derived from compounds with formula (I″), particularly formula (I), may be used as catalysts. In particular they may be used as catalysts in epoxidation reactions, particularly asymmetric epoxidation reactions.
According to one embodiment, metallic complexes derived from compounds with formula (I″), particularly formula (I), may be used as imaging and/or radiotherapy agents, or used in radioimmunotherapy or in theranostic. Thus, the invention also relates in certain embodiments to the use of complexes according as disclosed herein for imaging by single photon emission computed tomography (SPECT), positron emission tomography (PET) or magnetic resonance imaging (MRI).
According to one embodiment, metallic complexes derived from compounds with formula (I″), particularly formula (I), may be used in multimodal imaging such as for example SPECT/optical imaging (OI), PET/OI, PET/MRI, SPECT/MRI, MRI/OI.
According to one embodiment, the metallic complexes derived from compounds with formula (I″), particularly formula (I), may be used as biological molecule markers particularly as peptide or antibody markers.
Certain embodiments of the present invention also relate to compounds obtained by coupling biological molecules with a ligand with formula (I) as disclosed herein that may or may not be complexed with a metal. When coupling the ligand according to these and related embodiments with a biological molecule, a spacer group may be used between the ligand and the biological molecule. According to one embodiment, the spacer may for example be a PEG group.
Embodiments of the present invention will be better understood after reading the following examples that provide non-limitative illustrations of the invention.
A solution of chloroacetaldehyde (50% in H2O, 98.8 g, 0.63 mol) in 500 mL of acetonitrile are added drop by drop at 20° C. to a solution of diethylenetriamine (64.9 g, 0.63 mol) and K2CO3 (1.23 mol, 173.9 g, 2 eq) in 1 L of acetonitrile. The mix is stirred at ambient temperature for 6 h. After filtration on celite, the solvent is evaporated. 800 mL of diethyl ether are added onto the residual oil, non-soluble impurities are eliminated by filtration. After evaporation of the solvent, the compound 1 is obtained in the form of a yellow oil (m=56.8 g, yield=71%). 1H NMR (300 MHz, CDCl3, 298 K) δ (ppm): 1.60-1.81 (bs, 2H, NH); 1.93-2.04 (m, 2H); 2.23 (dd, 1H, 2J=11.6 Hz, 3J=8.0 Hz, CH2CH); 2.43-2.45 (m, 2H); 2.56-2.63 (m, 3H); 2.73-2.77 (m, 2H); 2.87 (dd, 1H, 2J=11.6, 3J=2.6 Hz, CH2CH). 13C{11-1} NMR (75 MHz, CDCl3, 298 K) δ(ppm): 42.1; 44.3; 48.4; 50.2 51.6 (CH2u); 75.7 (CH).
353.9 g of benzyl bromide (2.06 mol, 3 equivalents) are added drop by drop at 10° C. to a solution of 1 (87.61 g, 0.69 mol) and 380 g of potassium carbonate (2.76 mol, 4 equivalents) in 1.8 L of acetonitrile. The mix is stirred at ambient temperature for 24 h. After filtration on celite, the solvent is evaporated, and 1.8 L of ethanol are added on the residual oil. 26 g of sodium borohydride (0.69 mol, 1 equivalent) are added at −10° C. After 12 hours, the solvent is evaporated and oil is dissolved in chloroform and ether. The solvent is evaporated and oil is dissolved in ethanol (200 mL) and 100 mL of hydrochloric acid are added. The mix is evaporated to dry and 500 mL of acetone are added on the residual oil, the white precipitate formed is isolated by filtration and then recrystallised in water (400 mL). The crystals are filtered, a solution of 13 M NaOH is added slowly until pH>12 is reached. After extraction with chloroform, the organic phase is dried on MgSO4. After filtration and evaporation of the solvent, the compound 2 is obtained in the form of a colourless oil (m=102 g, yield=37%). 1H NMR (300 MHz, CDCl3, 300 K) δ(ppm): 2.86 (s, 12H); 3.65 (s, 6H); 7.28-7.36 (m, 15H). 13C{1H} NMR (75 MHz, CDCl3, 300 K) δ(ppm): (CH2) 55.4 (*6); (CH2) 63.0 (*3); (CH(ar)) 126.7 (*3); 128.1 (*6); 129.1 (*6); (Car) 140.4 (*3). MALDI-TOF: m/z=399.87 [M+].
84.77 g of compound 2 (0.21 mol) are placed in 1 L of acetic acid with 9 g of Pd/C at 10% (8 mmol, 0.04 equivalent) under H2. After consumption of 14.3 L of hydrogen (0.63 mol, 3 equivalents), the mix is filtered on celite and the solvent is evaporated. 52 mL of hydrochloric acid are added, followed by 250 mL of ethanol. The precipitate obtained is filtered and washed with 200 mL of diethyl ether. The compound 3 is obtained in the form of a white solid (25 g, yield=95%). 1H NMR (300 MHz, D2O, 300 K) δ(ppm): 3.47 (s, 12H). 13C{1H} NMR (75 MHz, D2O, 300 K) δ(ppm): (CH2) 42.4. MALDI-TOF: m/z=129.70 [M+].
259.3 g of benzyl bromide (1.5 mol, 3 equivalents) are added drop by drop to a solution of 1 (64.3 g, 0.5 mol) and 278.8 g of K2CO3 (2.0 mol, 4 equivalents) in 1.1 L of acetonitrile at 10° C. The mix is stirred for 12 hours. 24.76 g of sodium cyanide (0.505 mol, 1 eq) are added carefully. The mix is stirred at ambient temperature for 4 days. After filtration on celite, the solvent is evaporated, 3 L of diethyl ether are added on the residual oil and insoluble impurities are eliminated by filtration. After evaporation of the solvent, the compound 4 is obtained in the form of a brown oil (137.2 g. yield=63%). 1H NMR (300 MHz. CDCl3. 298 K) δ(ppm): 1.53-1.78 (m. 1H); 2.43-2.56 (m. 4H); 2.66-2.74 (m. 1H); 2.82-2.88 (m. 2H); 2.95-2.99 (m. 1H); 3.14-3.22 (m. 1H); 3.42-3.53 (m. 1H); 3.63-3.84 (m. 6H); 7.19-7.33 (m. 15H). 13C{1H} NMR (75 MHz. CDCl3. 298 K) δ (ppm): 54.7 (CH); 55.5; 56.4; 57.4; 58.8; 61.4; 62.1; 63.5; 65.9 (CH2α); 118.0 (CN); 126.8; 127.1; 127.7; 128.0; 128.1; 128.2; 128.3; 128.4; 128.6; 128.8; 129.0; 129.1 (*2); 129.2; 129.4 (CHar) 138.2; 1 39.3; 139.9 (Car). ESI-MS: m/z=398.24 [M−CN+2H]+; 425.25 [M+H]+. IR (cm−1): 2250 (CN).
A solution of 4 (112.7 g, 0.27 mol) in 450 mL of THF is added very slowly at −78° C. under nitrogen to a suspension of 11.5 g of LiAlH4 (0.32 mol, 1.2 eq) in 450 mL of THF. The mix is stirred for 12 h. 100 mL of water are added carefully on the mix. After evaporation of the solvent, the grey-green solid obtained is dissolved in 1 L of chloroform, the solution is filtered on celite to eliminate impurities. After evaporation of the solvent, the brown residual oil is placed in 200 mL of acetone and 200 mL of HCl at 37% are added slowly. The white precipitate is isolated by filtration and is recrystallised in water to give the protonated form of compound 2 (83.9 g, 0.20 mol). The compound is deprotonated by the addition of a solution of 16 M soda until a pH of 12 is reached. After extraction with chloroform (2*500 mL) and drying of the organic phase on MgSO4, the solvent is evaporated. The compound 5 is obtained in the form of a yellow oil (45.3 g, yield=39%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.45 (m. 2H); 2.39-2.86 (m. 10H); 3.03-3.11 (m. 1H); 3.35-3.75 (m. 7H); 3.85 (bs. 1H); 7.24-7.44 (15H). 13C{1H} NMR (75 MHz. CDCl3. 298 K) δ (ppm): 42.5; 51.1; 52.8; 55.1; 55.6; 57.9; 58.2 (CH2α); 62.8 (CH); 63.5; 64.3 (CH2α) 126.7; 127.0; 127.1; 128.3 (*9); 128.8; 129.2; 129.5 (CHar); 140.2; 140.4; 141.2 (Car). ESI-MS: m/z=429.31 [M+H]+. HMRS-ESI: calculated m/z for C28H36N4+H=429.3012, obtained=429.3060.
The compound 5 (5.0 g, 11.7 mol) is dissolved in a mix of acetic acid (29 mL), water (29 mL) and THF (98 mL). 500 mg of Pd/C at 10% (0.47 mmol, 0.04 equivalent) are added under H2. After consumption of the expected hydrogen volume, palladium is eliminated by filtration on celite. After evaporation of the solvent, the residue is dissolved in ethanol (100 mL). 5 mL of hydrochloric acid at 37% are then added. After 1 hour, the precipitate formed is isolated by filtration and is then washed with 20 mL ethanol. The precipitate is recrystallised in water. The compound is deprotonated by addition of a solution of 16 M soda on the crystals until a pH of 12 is reached. After extraction with chloroform (2*500 mL), and drying of the organic phase on MgSO4, the solvent is evaporated to obtain 6 in the form of a yellow oil (m=0.79 g, yield=44%). 1H NMR (300 MHz, D2O, 300 K) δ (ppm): 2.98-3.58 (m, 13H). 13C {1H} NMR (75 MHz, D2O, 300 K) δ(ppm): (CH2) 40.9; 42.0; 42.9; 45.2; 46.2; 47.2; (CH) 50.6. MALDI-TOF: m/z=158.74 [M+].
A solution of Boc2O (4.20 g, 19.2 mmol) in CH2Cl2 (100 mL) is slowly added to 5 (8.24 g, 19.2 mmol) in CH2Cl2 (150 mL). The solution is stirred at ambient temperature for 24 h. After evaporation of the solvent, oil is purified by chromatography on alumina (eluant: CH2Cl2) in order to obtain compound 7 in the form of a yellow oil (m=7.38 g, yield=73%). 1H NMR (300 MHz. CDCl3, 298 K) δ(ppm): 1.42 (s, 9H. CH3); 2.34-2.67 (m, 8H); 2.83-2.92 (m, 1H); 2.97-3.16 (m, 2H); 3.35-3.65 (m, 7H); 4.05 (m, 1H); 4.94 (m, 1H); 7.15-7.33 (m, 15H). 13C{1H} NMR (150 MHz, CDCl3, 298 K) δ(ppm): 28.7 (*3) (CH3); 40.7; 50.6; 53.2; 55.3; 56.2; 57.9; 58.1 (CH2); 58.5 (CH); 63.8; 64.2 (CH2); 79.0 (C); 126.8; 127.0; 127.2; 128.4 (*6); 129.0 (*2); 129.2 (*2); 129.5 (*2) (CHar); 140.1; 140.3; 140.7 (Car); 156.3 (C═O). ESI-MS: m/z=529.35 [M+H]+. HMRS-ESI: m/z calculated for C33H44N4O2+H=529.3537, obtained=529.3528.
Compound 7 (3.33 g, 6.30 mmol) is dissolved in a mix of acetic acid (20 mL), water (20 mL) and THF (60 mL). 266 mg of Pd/C at 10% (0.25 mmol, 0.04 equivalent) are added under H2. After consumption of the expected hydrogen volume, palladium is eliminated by filtration on celite. After evaporation of the solvent, the residue is dissolved in ethanol (100 mL). 5 mL of a 3 M hydrochloric acid solution are then added. After 1 hour, the precipitate formed is isolated by filtration and is then washed with 20 mL of ethanol and dried under a vacuum to give a white powder. The compound is deprotonated by the addition of a 3 M soda solution. After extraction with chloroform (2*50 mL), and drying of the organic phase on MgSO4, the solvent is evaporated to obtain 8 in the form of a yellow oil (m=1.30 g, yield=80%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.39 (s, 9H, CH3); 2.35-3.24 (m, 13H); 4.28-4.55 (m, 3H, NH); 5.83 (s, 1H, NHC═O), 13C{1H} NMR (150 MHz, CDCl3, 298 K) δ(ppm): 28.6 (*3) (CH3); 43.1; 44.0; 44.6; 45.6; 45.9 (CH2); 46.8 (CH); 79.5 (C); 156.8 (C═O). ESI-MS: m/z=203.15 [M-tBu+H]+; 259.15 [M+H]+. HMRS-ESI: calculated m/z for C12H27N4O2=259.212; obtained=259.2116.
420 mg de 8 (1.12 mmol) and 818 mg of diethoxymethylphosphine (6.01 mmol) are placed in a tank under nitrogen bubbling for 5 minutes. The mix is then heated to 80° C. 189 mg of paraformaldehyde (6.01 mmol) are added and the mix is stirred for 2 h. After returning to ambient temperature, water is added (5 mL) and a 3M HCl solution is added until a pH of 5 is reached. The solution is washed twice with 30 mL of diethyl ether. A solution of 3M NaOH soda is slowly added until the pH is 13. The aqueous phase is washed with 2*50 mL of chloroform. The organic phase is dried on MgSO4. After evaporation of the solvent, the residual oil is purified by Flash chromatography on silica (A: CH2Cl2, B: MeOH, B 0% 60%, rt=4.2 min). The compound 9 is obtained in the form of a yellow oil (m=360 mg, yield=58%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.30 (t, 9H, 2J=7 Hz, PCH3); 1.41 (s, 9H, CH3); 1.45-1.54 (m, 9H, PCH2CH3); 2.77-3.15 (m, 19H); 4.06 (m, 6H, PCH2CH3); 5.83 (s, 1H, NH).
10 mL of a 37% HCl solution are added to 60 mg of compound 9 (0.10 mmol). The mix is heated to 90° C. for 2 days. After evaporation, the compound 10 (3HCl) is isolated in the form of a white powder (m=54.4 mg, yield=100%). 1H NMR (500 MHz, D2O, 298 K) δ(ppm): 1.37-1.49 (m, 9H), 2.82-3.60 (m, 19H). 31P {1H} NMR (202 MHz, D2O, 298 K) δ(ppm): 38.4; 45.2; 49.2. ESI-MS: m/z=435.17 [M+H]+; 457.15 [M+Na]+. HMRS-ESI: calculated for C13H33N4O6P3+H, 435.1686; obtained 435.1696; calculated for C13H33N4O6P3+Na 457.1505; obtained 457.1511.
An excess of acetic anhydride (100 μL) was added to 20 mg of compound 10 (0.041 mmol). At first our compound was not dissolved completely in acetic anhydride but after one night stirring at room temperature, a clear brown solution is obtained. Excess of acetic anhydride was removed by addition of 1 mL of water and evaporation. This was repeated twice and finally the solution in water was freeze-dried. The compound 11 was obtained as a light brown powder (m=14.5 mg, yield=70%). 1H NMR (300 MHz, D2O, 300 K) δ (ppm): 1.50 (d, 9H, 2J=13.5 Hz, PCH3), 2.02 (s, 3H, C═OCH3), 2.95-3.96 (m, 19H). 31P{1H} NMR (300 MHz, D2O, 300 K) δ (ppm): 37.9, 39.3, 47.4. MALDI-TOF: m/z=477.00 [M+H]+, 498.98 [M+Na]+. HRMS-ESI: m/z=calculated for C15H35N4O2P3+H−: 477.1791, obtained 477.1778.
A solution of tertbutyl bromoacetate (4.66 g, 23.89 mmol) is added to a solution of 6 (756 mg, 4.79 mmol) and K2CO3 (6.61 g, 4.89 mmol) in 16 mL of acetonitrile. The mix is heated to 45° C. for 24 h. After returning to ambient temperature, the solution is filtered on celite and the solvent is evaporated. The residual oil is dissolved in ether and impurities are eliminated by filtration. The residue is purified by chromatography on alumina (eluant: CH2Cl2/MeOH 99:1), to give 12 in the form of a yellow oil (m=1.89 mg, yield=54%). 1H NMR (300 MHz, CDCl3, 298 K) δ (ppm): 1.38-1.41 (m, 45H, CH3); 2.43 (dd, 1H, J=13.2, 7.7 Hz); 2.60-3.11 (m, 11H); 3.19-3.45 (m, 10H); 4.02-4.13 (m, 1H). 13C{1H} NMR (75 MHz, CDCl3, 298K) δ (ppm): 28.4 (*15) (CH3); 52.4; 53.6; 54.7; 55.3; 55.4; 55.7; 55.9; 56.0; 56.2; 57.0; 59.8; 61.1 (CH2+CH); 80.4; 80.6; 80.7; 80.8 (*2) (C); 171.0 (*2); 171.7; 171.8; 172.3 (C═O). ESI-MS: m/z=729.5 [M+H]+; 751.5 [M+Na]+.
10 mL of a 37% hydrochloric acid solution are added to 50 mg of compound 12 (0.07 mmol). The mix is stirred for 1 hour at ambient temperature. After evaporation of the solvent, the precipitate obtained is washed with 40 mL of acetone. After filtration, the compound 13 is obtained in the form of a white solid (m=360 mg, yield=58%). ESI-MS: m/z=449.3 [M+H]+; 471.2 [M+Na]+; 493.2 [M+2NaH]+. HMRS-ESI: calculated m/z for C17H28N4O10+H 449.1878; obtained 449.1858.
9.85 g of 2-(bromomethyl)pyridine bromohydrate (39.0 mmol, 3 eq) are slowly added at 10° C. to a solution of 1 (1.62 g, 13.0 mmol) and 45.5 g de K2CO3 in 90 mL of acetonitrile. The mix is stirred at ambient temperature for 24 h. After filtration on celite, the solvent is evaporated. The residual oil is dissolved in 200 mL of diethyl ether and the solution is stirred for 24 h. The precipitate is isolated by filtration, washed with 2*20 mL of diethyl ether and then dried under a vacuum to give 12.96 g of rectional intermediary. 5.0 g of this intermediary (10.3 mmol) are placed in 45 mL of ethanol and 3.9 g of NaBH4 (103.0 mmol) are added at −10° C. After 12 h, the solvent is evaporated and 50 mL of diethyl ether are added on the residual oil. Impurities are eliminated by filtration and the solvent is evaporated. The compound 14 is obtained in the form of an orange oil (m=1.62 g, yield=31%). 1H NMR (300 MHz, CDCl3, 298 K) δ (ppm): 3.06 (s, 12H); 4.34 (s, 6H); 7.80-7.84 (m, 3H); 7.92-7.95 (m, 3H); 8.33-8.39 (m, 3H); 8.64-8.66 (m, 3H). 13C {1H} NMR (75 MHz, CDCl3, 298K) δ (ppm): 49.3 (*6); 56.3 (*3); 126.4 (*3); 127.3 (*3); 143.5 (*3); 145.6 (*3); 150.3 (*3). ESI-MS: m/z=403.26 [M+H]+.
101 mg of 3-(prop-2-ynyloxy)benzaldehyde (0.63 mmol) are added to a solution of 6 (100 mg, 0.63 mmol) in 25 mL of ethanol, and the mix is stirred at ambient temperature for 48 h. The solvent is then evaporated and 25 mL of diethylether are added on the residual oil. After 12 h, the impurities are eliminated by filtration on celite. The solvent is evaporated, oil is placed in 10 mL of ethanol and 250 mg of NaBH4 (6.7 mmol) are added at 0° C. The mix is stirred at ambient temperature for 24 h. The solvent is evaporated, 25 mL of dichloromethane are added on the residual solid and impurities are eliminated by filtration. The solution is washed with a 3M soda solution (10 mL), dried on MgSO4 and the solvent is evaporated. The compound 15 is obtained in the form of a white solid (m=135 mg, yield=68%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.10-1.60 (m, 3H); 2.30-2.90 (m, 15H); 3.65 (s, 2H); 4.61 (d, 2H, 4J=2.3 Hz); 6.86 (d, 2H, 3J=8.7 Hz); 7.18 (d, 2H, 3J=8.7 Hz). 13C {1H} NMR (75 MHz, CDCl3, 298K) δ (ppm): 46.0; 46.4; 47.0; 47.2; 47.3; 49.9; 53.6; 55.6; 55.9; 75.6; 78.8; 114.8 (*2); 129.3 (*2); 130.1; 156.6. ESI-MS: m/z=303.22 [M+H]+.
A solution of tertbutyl bromoacetate (341 mg, 1.75 mmol) is added to a solution of 15 (135 mg, 0.44 mmol) and K2CO3 (484 mg, 3.50 mmol) in acetonitrile (15 mL). The mix is heated to 45° C. for 24 h. After returning to ambient temperature, the solution is filtered on celite. The solvent is evaporated, 50 mL of diethyl ether are added on the residual oil. Impurities are eliminated by filtration and the solvent is once again evaporated. Oil is purified by chromatography on alumina (eluant: CH2Cl2/MeOH 99:1). The compound 16 is obtained in the form of a yellow oil (m=100 mg, yield=30%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.36-1.42 (m, 36H); 2.49 (t, 1H, 2J=2.49 Hz); 2.50-3.77 (m, 23H); 4.61 (d, 2H, 4J=2.3 Hz); 6.83 (d, 2H, 3J=8.2 Hz); 7.18 (d, 2H, 3J=8.2 Hz). ESI-MS: m/z=759.50 [M+H]+; 771.57 [M+Na]+.
195 mg of 4,4-difluoro-8-(4-((1-carboxy-2-(4-nitrophenyl)ethyl)carbamoyl)phenyl) 1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza-s-indacene (0.32 mmol), 42 mg of hydroxybenzotriazole (HOBt) (0.32 mmol) and 60 mg of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDCI) (0.32 mmol) are successively added to a solution of 6 (50 mg, 0.32 mmol) in 10 mL of DMF. The mixed is stirred at ambient temperature and the reaction is followed by CCM (CH2Cl2/MeOH/NH4OH 10:85:5). The solvent is then evaporated. The red oil is dissolved in 20 mL of dichloromethane and washed three times with 10 mL of water. The organic phase is isolated and then dried on MgSO4. The red oil is purified by chromatography on silica gel (EtOH/NH4OH 80:20). The oil obtained is then dissolved in a CH2Cl2/hexane mix, the precipitate formed is isolated by filtration. The compound 17 is obtained in the form of a red solid (m=180 mg, yield=74%). 1H NMR (300 MHz, MeOD, 300 K) δ (ppm): 0.94 (t, 6H, 3J=7.5 Hz), 1.24 (s, 6H); 2.29 (q, 4H, 3J=7.5 Hz); 2.38 (s, 6H); 2.48-2.60 (m, 1H); 2.61-3.22 (m, 12H); 3.27-3.40 (m, 2H); 4.83-4.90 (m, 1H); 7.39 (d, 2H, 3J=8.1 Hz); 7.54 (d, 2H, 3J=8.5 Hz); 7.93 (d, 2H, 3J=8.5 Hz); 8.11 (d, 2H, 3J=8.1 Hz).
A solution of Boc2O (5.79 g, 26.6 mol) diluted in 30 mL of dichloromethane is added drop by drop to solution 1 (1.69 g, 13.3 mmol) in dichloromethane (30 mL). The mixed is stirred at ambient temperature for 24 h. After evaporation of the solvent, oil is dissolved in 50 mL of diethyl ether and the impurities are eliminated by filtration. The compound 18 is isolated in the form of a light brown solid (m=3.98 g, yield=91%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 3.32-3.39 (m, 18H); 4.37-4.67 (m, 2H); 4.73-5.98 (m, 8H); 6.44 (m, 1H). ESI-MS: m/z=328.15 [M+H]+.
A solution of benzyl bromide (742 mg, 4.3 mmol) diluted in acetonitrile (5 mL) is added at 0° C. to a solution of 18 (1.45 g, 4.34 mmol) in acetonitrile (10 mL). The mix is stirred at ambient temperature for 24 h. After evaporation of the solvent, oil is dissolved in 20 mL of diethyl ether, the precipitate is filtered, washed with 2*10 mL of diethyl ether and dried under a vacuum. The compound 19 is obtained in the form of a beige solid (m=1.31 g, yield=61%). 1H NMR (500 MHz, CDCl3, 320 K) δ(ppm): 11.35 (s, 9H); 1.51 (s, 9H); 3.58-3.66 (m, 2H); 3.70-3.78 (m, 1H); 3.81-3.93 (m, 3H); 4.13-4.20 (m, 1H); 4.46 (m, 1H); 4.56-4.65 (m, 1H); 4.75 (d, 1H, 2J=12.3 Hz); 4.83 (m, 1H); 5.19 (m, 1H); 5.46 (d, 1H, 2J=12.3 Hz); 7.45-7.51 (m, 3H); 7.59 (d, 2H, 3J=7.1 Hz). ESI-MS: m/z=418.27 [M-Br]+.
0.7 mL of a solution of 1M HCl are added very slowly to 19 (0.34 mg, 0.7 mmol). The solution is stirred for 1 h at ambient temperature. After evaporation of the solvent, compound 20 is obtained in the form of a white solid (m=0.07 mg, yield=36%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 3.09-3.11 (m, 2H); 3.34-3.48 (m, 8H); 4.37 (s, 2H); 5.30-5.34 (m, 1H); 7.52 (m, 5H). ESI-MS: m/z=218.16 [M-Br]+.
A solution of iodomethane (0.92 mg, 6.5 mmol) in acetonitrile (5 mL) is added drop by drop at 0° C. to a solution of 18 (2.12 g, 6.5 mmol) in acetonitrile (10 mL). The mix is stirred for 24 hours at ambient temperature. After evaporation of the solvent, the oil is dissolved in 30 mL of diethyl ether, the precipitate is filtered and washed with 2*10 mL of diethyl ether and dried under a vacuum. The compound 21 is obtained in the form of a yellow solid (m=1.78 g, yield=59%). 1H NMR (300 MHz, CDCl3, 298 K) δ(ppm): 1.40-1.48 (m, 21H); 3.70-4.74 (m, 10H); 5.0 (m, 1H). ESI-MS: m/z=230.12 [M-I-2tBu+2H]+, 286.19 [M-1-tBu+H]+; 342.25 [M-I]+.
A solution of chloroacetaldehyde (50% in water, 2.36 g, 15 mmol) is added to a solution of triethylenetetraamine (3 g, 15 mmol) in 70 mL of acetonitrile at ambient temperature. The mixed is stirred for 5 h. After evaporation of the solvent, the two isomers 22 and 22′ are obtained in the form of a yellow oil and will be used without additional purification (m=2.55 g, yield=100%). 13C{1H} NMR (75 MHz, CDCl3, 300 K) δ(ppm): (CH2) 38.8; 40.8; 41.7; 43.6; 45.0; 48.7; 49.3; 49.4; 49.9; 51.0; 52.0; 52.1; 52.4; 52.6; (CH) 75.8; 81.7. MALDI-TOF: m/z=170.71 [M+].
45.55 g of benzyl bromide (0.27 mol, 4 equivalents) are slowly added to a solution of 22 and 22′ (11.32 g, 66 mmol) and 37.3 g of potassium carbonate (0.27 mol, 4 equivalents) in 250 mL of acetonitrile. The mix is stirred at ambient temperature for 24 h. After filtration on celite, the solvent is evaporated, oil is dissolved in 250 mL of ethanol and 2.5 g of sodium borohydride (66 mmol, 1 equivalent) are added at 0° C. After 12 h, the solvent is evaporated and 150 mL of chloroform are added. Insoluble impurities are eliminated by filtration. After evaporation of the solvent, oil is purified by chromatography on alumina (solvent: CH2Cl2). After evaporation of the solvent, 500 mL of pentane are added on the residual oil, the solution is filtered and the solvent is evaporated. The compound 23 is obtained in the form of a yellow oil (m=16 g, 30 mmol, yield=45%). 1H NMR (300 MHz, CDCl3, 300 K) δ(ppm): 2.49-2.87 (m, 16H); 3.47 (s, 2H); 3.56 (s, 4H); 3.64 (s, 2H); 7.22-7.41 (m, 20H). 13C{1H} NMR (75 MHz, CDCl3, 300 K) δ(ppm): (CH2) 51.4; 52.2; 52.3; 52.3; 55.4; 55.8; 56.3; 58.8 (*2); 58.9; 59.3; 63.2; (CHar) 126.8 (*4); 128.1 (*8); 128.7 (*8); (Car) 139.8 (*4). MALDI-TOF: m/z=533.06 [M+].
12.37 g of 23 (23 mmol) are placed in 130 mL of acetic acid with 1 g of Pd/C at 10% (0.04 equivalent, 1 mmol) under H2. After consumption of 2.06 L of hydrogen (0.92 mol, 4 equivalents), palladium is eliminated by filtration and the solvent is evaporated. 7.7 mL of 37% HCl is added to the residual oil, then 50 mL of ethanol, forming a white precipitate. After filtration, the compound 24 is obtained in the form of a white solid (m=7.3 g, 23 mmol, yield=100%). 1H NMR (300 MHz, D2O, 300 K) δ(ppm): 3.33-3.57 (m, 16H). 13C{1H} NMR (75 MHz, D2O, 300 K) δ(ppm): (CH2) 35.3 (*2); 43.3 (*2); 43.3; 44.6 (*2); 51.7. MALDI-TOF: m/z=172.41 [M+].
A solution of compound 8 (471.1 mg, 1.84 mmol) in dimethylformamide (9.2 mL) was heated at 40° C. Tert-butylbromoacetate (0.803 mL, 5.51 mmol) and potassium carbonate (1.78 g, 12.9 mmol) were added to this solution and the reaction mixture was stirred overnight. The suspension was filtered on a celite bed and the filter-cake was washed with chloroform. After evaporation of the solvents in vacuo, the crude was purified by flash chromatography on silica gel (eluent: CH2Cl2/CH3OH 94:6) and inverse phase flash chromatography (eluent: {HCOOH/H2O 0.01M}/CH3CN 60:40). 25 was obtained as a light yellow oil (m=50.5 mg, yield=5%). 1H NMR (600 MHz, CDCl3, 325 K) δ(ppm): 1.39, 1.40, 1.43, 1.44 (4 s, 36H, CH3), 2.64-3.26 (m, 12H), 3.27-3.38 (m, 2H), 3.43 (d, 1H, 2J=17.6 Hz), 3.60 (d, 1H, 2J=17.6 Hz), 3.68 (d, 1H, 2J=17.6 Hz), 3.70 (d, 1H, 2J=17.6 Hz), 3.79 (d, 1H, 2J=17.6 Hz), 6.03 (bs, 1H, NHBoc). 13C{1H} NMR (75 MHz, CDCl3, 298 K) δ(ppm): 28.1, 28.2, 28.3, 28.6 (CH3), 39.3 (CH2NH) 51.6, 53.3, 55.9, 56.8, 79.8, 82.1, 82.5, 83.1 (CqtBu), 156.7 (CONHOtBu), 167.4, 168.8, 171.3. ESI-MS: m/z=601.46 [M+H]+. HRMS-ESI: m/z=calculated for C30H56N4O8+H, 601.4171 obtained 601.4145.
Trifluoroacetic acid (1 mL) was added to a stirred solution of compound 25 (49.5 mg, 0.08 mmol) in dichloromethane (2 mL). The resulting reaction mixture was stirred overnight at room temperature before it was concentrated in vacuo. Compound 26 was obtained as a light yellow oil and was directly used without purification. 1H NMR (300 MHz, D2O, 295 K) δ(ppm): 2.36-3.19 (m, 7H), 3.20-3.27 (m, 2H), 3.29-3.44 (m, 3H), 3.53-3.88 (m, 4H), 3.92-4.25 (m, 3H). ESI-MS: m/z=333.27 [M+H]+.
N,N-Diisopropylethylamine was added dropwise to a stirred solution of 26 (0.082 mmol) in water (2 mL) until pH reached 9.4. The solution is yellowish. Quickly, N-succinimidyl-4-nitrophenylacetate (22.8 mg, 0.082 mmol) dissolved in acetonitrile (1 mL) was added and the reaction mixture turned immediately red. The solution is stirred for 2 hours and the solvents are evaporated in vacuo and freeze-dried. To remove some impurities the crude compound was diluted in water (5 mL) and chloroform (5 mL). The aqueous phase was washed with chloroform (2×5 mL) and the organic phase was extracted with water (5 mL). The combined aqueous layers were freeze-dried and 27 was obtained as a light brown powder and was directly used without purification. ESI-MS: m/z=494.06 [M−H]−.
Compound 27 (0.082 mmol) was dissolved in water (1.4 mL) and 3.5 mg of 10% Pd/C (3.10−3 mmol, 0.04 equivalent) was added under H2. The solution was stirred vigourously and after consumption of hydrogen, the mixture was filtered on a celite bed to remove palladium and the filter-cake was washed with water. The crude compound was freeze-dried and 28 was obtained as a light yellow powder and was directly used without purification. ESI-MS: m/z=464.09 DA-Hy.
Compound 28 (0.082 mmol) was dissolved in water (1.4 mL) and the solution was stirred vigourously. In a test tube thiophosgene (37.8 μL, 0.49 mmol) was dissolved in dichloromethane (0.45 mL) and the mixture was added to the previous solution rapidly. The reaction was stirred for 3 hours. The aqueous phase was isolated and washed with chloroform. The crude compound was purified by semi-preparative HPLC column (System 3, tr=32.3 min) to obtained 29 as a light brown powder (5.0 mg, 0.010 mmol). The overall yield of the last four reactions is 12%. 1H NMR (300 MHz, D2O, 295 K) δ(ppm): 2.61-2.75 (m, 1H), 2.78-2.91 (m, 1H), 2.94-3.50 (m, 12H), 3.58 (s, 2H, PhCH2CO), 3.65-4.05 (m, 5H), 7.31 (s, 4H, CHar). ESI-MS: m/z=507.98 [M+H]+. HRMS-ESI: m/z=calculated for C22H29N5O7S+H, 508.1861 obtained 508.1881. m/z=calculated for C22H29N5O7S+Na: 530.1680 obtained 530.1687. Elemental analysis for C22H29N5O7S+CHCl3+2 H2O: Calculated: C (41.67%), H (5.17%), N (10.56%), S (4.84%). Obtained: C (41.32%), H (5.23%), N (10.75%), S (3.06%).
Compound 30 was obtained in three steps reaction starting from compound 10 by following the same procedure described for the preparation of compound 29 (Example P above).
| Number | Date | Country | Kind |
|---|---|---|---|
| FR1261091 | Nov 2012 | FR | national |
