Patent Application
20140012032
This invention relates to compounds and methods, which provide access to F-18 labeled stilbene derivatives.
4-[(E)-2-(4-{2-[2-(2-fluoroethoxy)ethoxy]ethoxy}phenyl)vinyl]-N-methylaniline has been labeled with [F-18]fluoride and is claimed by patent application WO2006066104 and members of the corresponding patent family.
The usefulness of this radiotracer for the detection of Aβ plaques have been reported in the literature (W. Zhang et al., Nuclear Medicine and Biology 32 (2005) 799-809; C. Rowe et al., Lancet Neurology 7 (2008) 1-7).
The synthesis of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline has been described before:
Very recently, further methods have been described:
So far, one-pot radiolabelings have been performed using a mesylate precursor. It is know, that for F-18 labeling of stilbenes, mesylates have advantages over corresponding tosylates by providing more clean reactions with less amount of by-products (W. Zhang et al. Journal of Medicinal Chemistry 48 (2005) 5980-5988), whereas the purification starting from the tosylate precursor was tedious and time consuming resulting in a low yield.
In contrast to this teaching of the prior art, we found advantages of tosylate and further arylsulfonate precursors for 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)vinyl]-N-methylaniline compared to the corresponding mesylate. Less non-radioactive by-products that eluted close to the retention time of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)vinyl]-N-methylaniline were found in the crude products if arylsulfonate precursors were used (Example 2-Example 6) compared to the crude mixture that was obtained after conversion of the mesylate precursor (Example 1).
The favorable by-product profile after radiolabeling of tosylate precursor 2b (
In a first aspect the present invention is directed to a compound of Formula II
wherein:
R is selected from the group comprising
PG is an “amine-protecting group”.
In a preferred embodiment, PG is selected from the group comprising:
More preferably, PG is Boc.
In a preferred embodiment LG is contains 0-3 fluorine atoms.
In a preferred embodiment Arylsulfonyloxy is selected from the group consisting of:
p-Toluenesulfonyloxy, 4-Cyanophenylsulfonyloxy, 4-Bromophenylsulfonyloxy, 4-Nitrophenylsulfonyloxy, 2-Nitrophenylsulfonyloxy, 4-Isopropyl-phenylsulfonyloxy, 2,4,6-Triisopropyl-phenylsulfonyloxy, 2,4,6-Trimethylphenylsulfonyloxy, 4-tert-Butyl-phenylsulfonyloxy, 4-Adamantylphenylsulfonyloxy and 4-Methoxyphenylsulfonyloxy.
In a more preferred embodiment, Arylsulfonyloxy is selected from the group comprising:
a) p-Toluenesulfonyloxy
In a second aspect the present invention is directed to a method for producing compound of Formula I by reacting compound of Formula II
comprising the steps of:
Step 1 comprises a straight forward [F-18]fluoro labeling reaction from compounds of Formula II for obtaining compound of Formula I (if R═H) or compound of Formula III (if R=PG).
The radiolabeling method comprises the step of reacting a compound of Formula II with a F-18 fluorinating agent for obtaining a compound of Formula III or of Formula I In a preferred embodiment, the [F-18]fluoride derivative is 4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]-hexacosane K[F-18]F (crownether salt Kryptofix K[F-18]F), K[F-18]F, H[F-18]F, KH[F-18]F2, Cs[F-18]F, Na[F-18]F or tetraalkylammonium salt of [F-18]F (e.g. [F-18]tetrabutylammonium fluoride). More preferably, the fluorination agent is K[F-18]F, H[F-18]F, [F-18]tetrabutylammonium fluoride, Cs[F-18]F or KH[F-18]F2, most preferably K[F-18], Cs[F-18]F or [F-18]tetrabutylammonium fluoride.
The radiofluorination reactions are carried out in acetonitrile, dimethylsulfoxide or dimethylformamide or a mixture thereof. But also other solvents can be used which are well known to someone skilled in the art. Water and/or alcohols can be involved in such a reaction as co-solvent. The radiofluorination reactions are conducted for less than 60 minutes. Preferred reaction times are less than 30 minutes. Further preferred reaction times are less than 15 min. This and other conditions for such radiofluorination are known to experts (Coenen, Fluorine-18 Labeling Methods: Features and Possibilities of Basic Reactions, (2006), in: Schubiger P. A., Friebe M., Lehmann L., (eds), PET-Chemistry—The Driving Force in Molecular Imaging. Springer, Berlin Heidelberg, pp. 15-50).
In a preferred embodiment, the Radiofluorination of compound of Formula II is carried out in acetonitrile or in a mixture of acetonitrile and co-solvents, wherein the ratio of acetonitrile is at least 50%, more preferably 70%, even more preferably 90%.
In one embodiment, 1.5-75 μmol, preferably 7.5-40 μmol, more preferably 10-30 μmol, and even more preferably 12-25 μmol of compound of Formula II are used in Step 1.
In an other embodiment, 1.5-50 μmol/mL, preferably 5-25 μmol/mL, more preferably 7-20 μmol/mol of a solution of compound of Formula II in acetonitrile or an acetonitrile/co-solvent mixture are used in Step 1.
Optionally, if R=PG, Step 2 comprises the deprotection of compound of Formula III to obtain compound of Formula I. Reaction conditions are known or obvious to someone skilled in the art, which are chosen from but not limited to those described in the textbook Greene and Wuts, Protecting groups in Organic Synthesis, third edition, page 494-653, included herewith by reference. Preferred reaction conditions are addition of an acid and stirring at 0° C.-180° C.; addition of an base and heating at 0° C.-180° C.; or a combination thereof.
Preferably the Step 1 and Step 2 are performed in the same reaction vessel.
Step 3 comprises the purification and formulation of compound of Formula I. Methods for purification of radiotracers are well known to person skilled in the art and include HPLC methods as well as solid-phase extraction methods.
In one embodiment, the crude product mixture is purified by HPLC and the collected product fraction is further passed through a solid-phase cartridge to remove the HPLC solvent (such as acetonitrile) and to provide the compound of Formula I in an injectable Formulation.
In an other embodiment, the crude product mixture is purified by HPLC, wherein, the HPLC solvent mixture (e.g. mixtures of ethanol and aqueous buffers) can be part of the injectable Formulation of compound of Formula I. The collected product fraction can be diluted or mixed with other parts of the Formulation.
In an other embodiment, the crude product mixture is purified by solid-phase cartridges.
In a preferred embodiment, the method is carried out by use of a module (review: Krasikowa, Synthesis Modules and Automation in F-18 labeling (2006), in: Schubiger P. A., Friebe M., Lehmann L., (eds), PET-Chemistry—The Driving Force in Molecular Imaging. Springer, Berlin Heidelberg, pp. 289-316) which allows an automated synthesis. More preferably, the process is carried out by use of an one-pot module. Even more preferable, the process is carried out on commonly known non-cassette type modules (e.g. Ecker&Ziegler Modular-Lab, GE tracerlab FX, Raytest SynChrom) and cassette type modules (e.g. GE Tracerlab MX, GE Fastlab, IBA Synthera, Eckert&Ziegler Modular-Lab PharmTracer), optionally, further equipment such as HPLC or dispensing devices are attached to the said modules.
In a third aspect the present invention is directed to a fully automated and/or remote controlled method for production of compound of Formula I comprising the Steps and compounds as disclosed above.
In a preferred embodiment this method is a fully automated process, compliant with GMP guidelines, that provides a Formulation of Formula I for the use of administration (injection) into human.
In a fourth aspect the present invention is directed to a method for production of compounds of Formula II (with the provisio that R=PG) by reacting a compound of Formula IV with arylsulfonylhalides or arylsulfonic acid anhydrides or arylsulfonic acid, preferably with arylsulfonylhalides or arylsulfonic acid anhydrides. The formation of compounds of Formula II from compound of Formula IV can be mediated by a base or a coupling reagent as known to person skilled in the art.
wherein PG is described above.
In a fifth aspect the present invention is directed to a method for production of compounds of Formula II (with the provisio that R═H) by reacting a compound of Formula IV with arylsulfonylhalides or arylsulfonic acid anhydrides or arylsulfonic acid, preferably with arylsulfonylhalides or arylsulfonic acid anhydrides. The formation of compounds of Formula II from compound of Formula IV can be mediated by a base or coupling reagent as known to person skilled in the art.
Subsequent cleavage of PG leads to compounds of Formula II.
wherein PG is described above.
In a sixth aspect the present invention is directed to a Kit for the production of a pharmaceutical composition of compound of Formula I.
In one embodiment the Kit comprising a sealed vial containing a predetermined quantity of the compound of Formula II as disclosed in the first aspect.
Preferably, the Kit contains 1.5-75 μmol, preferably 7.5-50 μmol, more preferably 10-30 μmol, and more preferably 12-25 μmol of compound of Formula II.
Optionally, the Kit contains further components for manufacturing of compound of Formula I, such as solvents, solid-phase extraction cartridges, reagent for fluorination (as described above), reagent for cleavage of deprotection group, solvent or solvent mixtures for purification, solvents and excipient for formulation.
In one embodiment, the Kit contains a platform (e.g. cassette) for a “cassette-type module” (such as Tracerlab MX or IBA Synthera).
In the context of the present invention, preferred salts are pharmaceutically suitable salts of the compounds according to the invention. The invention also comprises salts which for their part are not suitable for pharmaceutical applications, but which can be used, for example, for isolating or purifying the compounds according to the invention.
Pharmaceutically suitable salts of the compounds according to the invention include acid addition salts of mineral acids, carboxylic acids and sulphonic acids, for example salts of hydrochloric acid, hydrobromic acid, sulphuric acid, phosphoric acid, methanesulphonic acid, ethanesulphonic acid, toluenesulphonic acid, benzenesulphonic acid, naphthalene disulphonic acid, acetic acid, trifluoroacetic acid, propionic acid, lactic acid, tartaric acid, malic acid, citric acid, fumaric acid, maleic acid and benzoic acid.
Pharmaceutically suitable salts of the compounds according to the invention also include salts of customary bases, such as, by way of example and by way of preference, alkali metal salts (for example sodium salts and potassium salts), alkaline earth metal salts (for example calcium salts and magnesium salts) and ammonium salts, derived from ammonia or organic amines having 1 to 16 carbon atoms, such as, by way of example and by way of preference, ethylamine, diethylamine, triethylamine, ethyldiisopropylamine, monoethanolamine, diethanolamine, triethanolamine, dicyclohexylamine, dimethylaminoethanol, procaine, diben-zylamine, N methylmorpholine, arginine, lysine, ethylenediamine and N methylpiperidine.
The term halogen or halo refers to Cl, Br, F or I.
The term “Arylsulfonyloxy” refers to
—O—S(O)2-Q wherein Q is optionally substituted aryl.
The term “aryl” as employed herein by itself or as part of another group refers to monocyclic or bicyclic aromatic groups containing from 6 to 10 carbons in the ring portion, such as phenyl, naphthyl or tetrahydronaphthyl.
Whenever the term “substituted” is used, it is meant to indicate that one or more hydrogens on the atom indicated in the expression using “substituted” is/are replaced by one ore multiple moieties from the group comprising halogen, nitro, cyano, trifluoromethyl, alkyl and O-alkyl, provided that the regular valency of the respective atom is not exceeded, and that the substitution results in a chemically stable compound, i.e. a compound that is sufficiently robust to survive isolation to a useful degree of purity from a reaction mixture.
The term “alkyl” as employed herein by itself or as part of another group refers to a C1-C10 straight chain or branched alkyl group such as, for example methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, heptyl, hexyl, decyl or adamantyl. Preferably, alkyl is C1-C6 straight chain or branched alkyl or C7-C10 straight chain or branched alkyl. Lower alkyl is a C1-C6 straight chain or branched alkyl.
The term “amine-protecting group” as employed herein by itself or as part of another group is known or obvious to someone skilled in the art, which is chosen from but not limited to a class of protecting groups namely carbamates, amides, imides, N-alkyl amines, N-aryl amines, imines, enamines, boranes, N—P protecting groups, N-sulfenyl, N-sulfonyl and N-silyl, and which is chosen from but not limited to those described in the textbook Greene and Wuts, Protecting groups in Organic Synthesis, third edition, page 494-653, included herewith by reference. The amine-protecting group is preferably Carbobenzyloxy (Cbz), p-Methoxybenzyl carbonyl (Moz or MeOZ), tert-Butyloxycarbonyl (BOC), 9-Fluorenylmethyloxycarbonyl (FMOC), Benzyl (Bn), p-Methoxybenzyl (PMB), 3,4-Dimethoxybenzyl (DMPM), p-methoxyphenyl (PMP) or the protected amino group is a 1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl (phthalimido) or an azido group.
The term “leaving group” as employed herein by itself or as part of another group is known or obvious to someone skilled in the art, and means that an atom or group of atoms is detachable from a chemical substance by a nucleophilic agent. Examples are given e.g. in Synthesis (1982), p. 85-125, table 2 (p. 86; (the last entry of this table 2 needs to be corrected: “n-C4F9S(O)2—O— nonaflat” instead of “n-C4H9S(O)2—O— nonaflat”), Carey and Sundberg, Organische Synthese, (1995), page 279-281, table 5.8; or Netscher, Recent Res. Dev. Org. Chem., 2003, 7, 71-83, scheme 1, 2, 10 and 15 and others). (Coenen, Fluorine-18 Labeling Methods: Features and Possibilities of Basic Reactions, (2006), in: Schubiger P. A., Friebe M., Lehmann L., (eds), PET-Chemistry—The Driving Force in Molecular Imaging. Springer, Berlin Heidelberg, pp. 15-50, explicitly: scheme 4 pp. 25, scheme 5 pp 28, table 4 pp 30, Fig 7 pp 33).
Unless otherwise specified, when referring to the compounds of Formula the present invention per se as well as to any pharmaceutical composition thereof the present invention includes all of the hydrates, salts, and complexes.
The term “F-18” means fluorine isotope 18F. The term“F-19” means fluorine isotope 19F.
The term “F-18” means fluorine isotope 18F. The term“F-19” means fluorine isotope 19F.
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2a (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 21% (corrected for decay).
4-Dimethylaminopyridine (26.7 mg) and triethylamine (225 μL) were added to a solution of 1.0 g tert-butyl {4-[(E)-2-(4-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}phenyl)vinyl]phenyl}methylcarbamate (4) in dichloromethane (12 mL) at 0° C. A solution of p-toluenesulfonyl chloride (417 mg) in dichloromethane (13.5 mL) was added at 0° C. The resulting mixture was stirred at room temperature over night. The solvent was removed under reduced pressure and the crude product was purified by flash chromatography (silica, 0-80% ethyl acetate in hexane). 850 mg 2b were obtained as colorless solid.
1H NMR (300 MHz, CDCl3) δ ppm 1.46 (s, 9H), 2.43 (s, 3H), 3.27 (s, 3H), 3.59-3.73 (m, 6H), 3.80-3.86 (m, 2H), 4.05-4.19 (m, 2H), 6.88-7.05 (m, 4H), 7.21 (d, J=8.3 Hz, 2H), 7.32 (d, J=8.3 Hz, 2H), 7.39-7-47 (m, 4H), 7.80 (d, J=8.3 Hz, 2H).
MS (ESIpos): m/z=612 (M+H)+
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2b (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 25% (corrected for decay).
To a stirred solution of 100 mg (0,219 mmol) tert-butyl-{4-[(E)-2-(4-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}phenyl)vinyl]phenyl}methylcarbamate (WO2006/066104) in 2 mL THF was added a solution of 140 mg (0.548 mmol) 4-brombenzene sulfonylchlorid in 3 mL THF drop by drop. The reaction mixture was cooled to 0° C. 156.8 mg (1.1 mmol) potassium trimethylsilanolat was added. The milky suspension was stirred at 0° C. for 2 hours and at 80° C. for another 2 hours. The reaction mixture was poured onto ice-cooled water. The aqueous solution was extracted with dichloromethane several times. The combined organic phases were dried with sodium sulphate and concentrated in vacuum. The crude product was purified using silica gel with ethyl acetate/hexane-gradient as mobile phase. The desired product 2c was obtained with 77 mg (0.114 mmol, 52.0% yield).
1H NMR (300 MHz, CDCl3) δ ppm 1.39 (s, 10H) 3.20 (s, 3H) 3.50-3.57 (m, 2H) 3.57-3.61 (m, 2H) 3.61-3.66 (m, 2H) 3.72-3.80 (m, 2H) 4.02-4.10 (m, 2H) 4.10-4.17 (m, 2H) 6.79-6.85 (m, 2H) 6.91 (d, J=8.10 Hz, 2H) 7.10-7.17 (m, 2H) 7.32-7.41 (m, 5H) 7.57-7.65 (m, 2H) 7.67-7.74 (m, 2H)
MS (ESIpos): m/z=676/678 (M+H)+
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2c (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 43% (corrected for decay).
To a stirred solution of 151 mg (0.330 mmol) tert-butyl-{4-[(E)-2-(4-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}phenyl)vinyl]phenyl}methylcarbamate (WO2006/066104), 4.03 mg (0,033 mmol) DMAP und 36.7 mg (363 mmol) triethylamine in 4 mL dichlormethane was added a solution of 97.4 mg (0,313 mmol) 4-(adamantan-1-yl)benzene sulfonylchloride in 1 mL dichlormethane at 0° C. The reaction mixture was stirred at 0° C. for 1 hour and over night at room temperature. 7.3 mg (0,072 mmol) triethylamin und 19.5 mg (0.062 mmol) 4-(adamantan-1-yl)benzenesulfonyl chloride were added to the reaction mixture. The reaction mixture was stirred at room temperature for 3 days. It was concentrated in vacuum. The crude product was purified using silica gel with ethyl acetate/hexane-gradient as mobile phase. The desired product 2d was obtained with 104 mg (0.142 mmol, 43.4% yield).
1H NMR (300 MHz, CDCl3) δ ppm 1.51 (s, 9H), 1.62 (s, 1H), 1.74-1.91 (m, 6H), 1.94 (d, J=3.20 Hz, 6H), 2.16 (br. s., 3H), 3.31 (s, 3H), 3.63-3.69 (m, 2H), 3.69-3.73 (m, 2H), 3.76 (dd, J=5.27, 4.52 Hz, 2H), 3.89 (d, J=4.90 Hz, 2H), 4.13-4.26 (m, 4H), 6.95 (d, J=8.85 Hz, 2H), 7.02 (d, J=8.29 Hz, 2H), 7.25 (d, J=8.48 Hz, 2H), 7.40-7.52 (m, 4H), 7.55 (m, J=8.67 Hz, 2H), 7.89 (m, J=8.67 Hz, 2H)
MS (ESIpos): m/z=732 (M+H)+
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2d (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 27% (corrected for decay).
To a stirred solution of 151 mg (0.330 mmol) tert-butyl-{4-[(E)-2-(4-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}phenyl)vinyl]phenyl}methylcarbamate (WO2006/066104), 4.03 mg (0.033 mmol) DMAP and 36.7 mg (0.363 mmol) triethylamine in 4 mL dichlormethane was added a solution of 63.2 mg (0.313 mmol) 4-cyanobenzenesulfonyl chloride in 1 mL dichlormethane at 0° C. The reaction mixture was stirred over night and concentrated in vacuum. The crude product was purified using silica gel with ethyl acetate/hexane-gradient as mobile phase. The desired product 2e was obtained with 118 mg (0.190 mmol, 57.6% yield).
1H NMR (400 MHz, CDCl3) δ ppm 1.47 (s, 9H) 3.28 (s, 3H) 3.58-3.63 (m, 2H) 3.63-3.68 (m, 2H) 3.70-3.75 (m, 2H) 3.81-3.87 (m, 2H) 4.11-4.18 (m, 2H) 4.24-4.30 (m, 2H) 6.91 (d, J=8.59 Hz, 2H) 6.99 (dt, 2H) 7.22 (d, J=8.34 Hz, 2H) 7.39-7.50 (m, 4H) 7.83 (m, J=8.59 Hz, 2H) 7.98-8.11 (m, 2H)
MS (ESIpos): m/z=623 (M+H)+
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2e (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 31% (corrected for decay).
To a stirred solution of 200 mg (0.437 mmol) tert-butyl-{4-[(E)-2-(4-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}phenyl)vinyl]phenyl}methylcarbamate (WO2006/066104), 5.34 mg (0.044 mmol) DMAP and 47.5 mg (0.470 mmol) triethylamine in 4 mL dichlormethane was added a solution of 92 mg (0,415 mmol) 2-nitrobenzenesulfonyl chloride in 1 mL dichlormethane at 0° C. The reaction mixture was stirred over night and concentrated in vacuum. The crude product was purified with ethyl acetate/hexane-gradient as mobile phase using silica gel. The desired product 2f was obtained with 77 mg (0.119 mmol, 59.5 yield).
1H NMR (400 MHz, CDCl3) δ ppm 1.39 (s, 9H) 3.20 (s, 3H) 3.55-3.63 (m, 4H) 3.59 (m, 4H) 3.69-3.74 (m, 2H) 3.75-3.80 (m, 2H) 4.06 (dd, J=5.68, 3.92 Hz, 2H) 4.32-4.37 (m, 2H) 6.80-6.84 (m, 2H) 6.84-6.98 (dt, 2H) 7.14 (d, J=8.59 Hz, 2H) 7.35 (d, J=3.03 Hz, 2H) 7.37 (d, J=2.78 Hz, 2H) 7.62-7.74 (m, 3H) 8.06-8.11 (m, 1H)
Radiolabeling was performed on a remote controlled synthesis module (Tracerlab FXN). Precursor 2e (2 mg) in 0.5 mL DMSO+0.5 mL acetonitrile was treated with dried potassium carbonate/kryptofix/[F-18]fluoride complex for 6 min at 100° C. 1M HCl (1 mL)+10 mg ascorbic acid was added and the mixture was heated for 4 min at 100° C. 2M NaOH (0.5 mL), water (6 mL) and ethanol (1 mL) were added and the crude mixture was trapped on a C18 cartridge. The crude product mixture was eluted with acetonitrile and diluted with 0.1M ammonium formiat buffer (1 mL)+5 mg ascorbic acid. A sample of the crude product was taken and analyzed by analytical HPLC (
Yield of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]ethoxy}phenyl)-vinyl]-N-methylaniline: 21% (corrected for decay).
The synthesis was performed on a Tracerlab MX synthesizer. [F-18]Fluoride (2.0 GBq) was trapped on a QMA cartridge (Waters). The activity was eluted into the reactor using an eluent mixture (22 mg kryptofix, 0.7 mL methanol, 0.1 mL 0.2M potassium mesylate solution, 0.01 mL tetrabutylammonium bicarbonate solution). The mixture was dried (heating, nitrogen stream, vacuum, addition of acetonitrile) and 7.0 mg precursor 2a in 1.5 mL tert-amyl alcohol+0.3 mL acetonitrile were added to the residue. After heating for 20 min at 120° C., the solvent was evaporated and a mixture of 2.2 mL 1.5M HCl, 1.1 mL acetonitrile and 30 mg sodium ascorbate was added. The resulting solution was heated for 7.5 min at 100° C. The crude product (910 MBq, 64% corrected for decay) was transferred to a vial and diluted with 1.5 mL 2M NaOH and 0.3 mL 0.1M ammonium formiate solution. A sample was analyzed by analytical HPLC (
The synthesis was performed on a Tracerlab MX synthesizer. [F-18]Fluoride (1.6 GBq) was trapped on a QMA cartridge (Waters). The activity was eluted into the reactor using an eluent mixture (22 mg kryptofix, 0.7 mL methanol, 0.1 mL 0.2M potassium mesylate solution, 0.01 mL tetrabutylammonium bicarbonate solution). The mixture was dried (heating, nitrogen stream, vacuum, addition of acetonitrile) and 8.0 mg precursor 2b in 1.5 mL tert-amyl alcohol+0.3 mL acetonitrile were added to the residue. After heating for 20 min at 120° C., the solvent was evaporated and a mixture of 2.2 mL 1.5M HCl, 1.1 mL acetonitrile and 30 mg sodium ascorbate was added. The resulting solution was heated for 7.5 min at 100° C. The crude product (775 MBq, 67% corrected for decay) was transferred to a vial and diluted with 1.5 mL 2M NaOH and 0.3 mL 0.1M ammonium formiate solution. A sample was analyzed by analytical HPLC (
For synthesis and purification of 4-[(E)-2-(4-{2-[2-(2-[F-18]fluoroethoxy)ethoxy]-ethoxy}phenyl)vinyl]-N-methylaniline on the Tracerlab MX, a Kit was assembled (Table 1).
The setup of the cassette on the MX module is illustrated in
200 mg 2-[2-(2-{4-[(E)-2-{4-[(tert-butoxycarbonyl)(methyl)amino]phenyl}-vinyl]phenoxy}ethoxy)ethoxy]ethyl 4-methylbenzenesulfonate (2b) were dissolved in 2.5 mL dichloromethane. 250 μL trifluoroacetic acid were added and the mixture was stirred for 4 h at room temperature. The solvent was removed under reduced pressure. The crude product was dissolved in dichlormethane (5 mL) and washed with sodium carbonate solution (10%, 2×2 mL). The organic layer was dried over sodium sulfate, the solvent was removed under reduced pressure and the residue was purified by flash chromatography (silica, 12-100% ethyl acetate in hexane). 84 mg 2g-1 were obtained as light red solid.
1H NMR (300 MHz, CDCl3) δ ppm 2.42 (s, 3H), 2.87 (s, 3H), 3.61-3.64 (m, 2H), 3.65-3.68 (m, 2H), 3.69-3.72 (m, 2H), 3.81-3.84 (m, 2H), 4.10-4.13 (m, 2H), 4.15-4.17 (m, 2H), 6.63 (d, J=8.3 Hz, 2H), 6.84-6.91 (m, 4H), 7.32 (d, J=7.9 Hz, 2H), 7.34 (d, J=8.7 Hz, 2H), 7.39 (d, J=8.7 Hz, 2H), 7.80 (d, J=8.3 Hz, 2H).
MS (ESIpos): m/z=512 (M+H)+
200 mg 2-[2-(2-{4-[(E)-2-{4-[(tert-butoxycarbonyl)(methyl)amino]phenyl}-vinyl]phenoxy}ethoxy)ethoxy]ethyl 4-methylbenzenesulfonate (2b) were dissolved in a 2M solution of HCl in diethyl ether. The mixture was stirred at room temperature for 72 h. The solvent was removed under reduced pressure. Diethyl ether was added and the precipitate was collected, washed with diethyl ether and dried under reduced pressure. 160 mg 2g-2 were obtained as light yellow solid.
1H NMR (300 MHz, CDCl3) δ ppm 2.43 (s, 3H), 3.03 (s, 3H), 3.62-3.64 (m, 2H), 3.66-3.68 (m, 2H), 3.69-3.72 (m, 2H), 3.82-3.85 (m, 2H), 4.12-4.14 (m, 2H), 4.16-4.18 (m, 2H), 6.88-6.94 (m, 3H), 7.04 (d, J=16.2 Hz, 1H), 7.32 (d, J=7.9 Hz, 2H), 7.42 (d, J=8.7 Hz, 2H), 7.49-7-56 (m, 4H), 7.80 (d, J=8.3 Hz, 2H).
MS (ESIpos): m/z=512 (M+H)+
200 mg 2-[2-(2-{4-[(E)-2-{4-[(tert-butoxycarbonyl)(methyl)amino]phenyl}-vinyl]phenoxy}ethoxy)ethoxy]ethyl 4-methylbenzenesulfonate (2b) were dissolved in 2.5 mL dichloromethane. 252 μL trifluoroacetic acid were added and the mixture was stirred for 5 h at room temperature. The solvent was removed under reduced pressure. The crude product was washed with hexane and diethyl ether and was dried under reduced pressure. 84 mg 2g-3 were obtained as light brown solid.
1H NMR (300 MHz, DMSO d6) δ ppm 2.40 (s, 3H), 2.72 (s, 3H), 3.46-3.50 (m, 2H), 3.51-3.55 (m, 2H), 3.57-3.61 (m, 2H), 3.69-3.73 (m, 2H), 4.10-4.09 (m, 2H), 4.10-4.13 (m, 2H),), 6.59-6.66 (m, 2H), 6.85-6.97 (m, 4H), 7.34 (d, J=8.3 Hz, 2H), 7.43 (d, J=8.8 Hz, 2H), 7.46 (d, J=8.1 Hz, 2H), 7.76 (d, J=8.3 Hz, 2H).
MS (ESIpos): m/z=512 (M+H)+
Radiolabelings have been performed using potassium carbonate/kryptofix or tetrabutylammonium hydroxide or tetrabutylammonium bicarbonate as reagent.
a) Radiolabeling with Potassium Carbonate/Kryptofix
[F-18]fluoride was trapped on a QMA cartridge. The activity was eluted using a solution of 7.5 mg kryptofix, 1 mg potassium carbonate in 1425 μL acetonitrile and 75 μL water. The mixture was dried under gentle nitrogen stream at 120° C. Drying was repeated after addition of 1 mL acetonitrile. The precursor (5.0 mg 2g-1 or 5.36 mg 2g-2 or 6.11 mg 2g-3) in 1 mg acetonitrile was added and the mixture was heated at 120° C. for 15 min. Fluoride incorporation was measured by radio-TLC (silica, ethyl acetate), results as summarized in Table 2.
b) Radiolabeling with Tetrabutylammonium Hydroxide
[F-18]fluoride was trapped on a QMA cartridge. The activity was eluted using a mixture of 300 μL≈b 4% (wt) n-Bu4OH and 600 μL acetonitrile. The mixture was dried under gentle nitrogen stream at 120° C. Drying was repeated after addition of 1 mL acetonitrile. The precursor (5.0 mg 2g-1 or 5.36 mg 2g-2 or 6.11 mg 2g-3) in 1 mg acetonitrile was added and the mixture was heated at 120° C. for 15 min. Fluoride incorporation was measured by radio-TLC (silica, ethyl acetate), results as summarized in Table 2.
c) Radiolabeling with Tetrabutylammonium Bicarbonate
[F-18]fluoride was trapped on a QMA cartridge. The activity was eluted using a mixture of 300 μL≈4% (wt) n-Bu4NHCO3 (a aqueous solution of 4% n-Bu4OH was saturated with carbon dioxide) and 600 μL acetonitrile. The mixture was dried under gentle nitrogen stream at 120° C. Drying was repeated after addition of 1 mL acetonitrile. The precursor (5.0 mg 2g-1 or 5.36 mg 2g-2 or 6.11 mg 2g-3) in 1 mL acetonitrile was added and the mixture was heated at 120° C. for 15 min. Fluoride incorporation was measured by radio-TLC (silica, ethyl acetate), results as summarized in Table 2.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10164946.5 | Jun 2010 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2011/058817 | 5/30/2011 | WO | 00 | 7/12/2013 |
