Synthesis and in vivo evaluation of 6-fluoro-a-methyl-L-tryptophan.

in American Chemical Society / Abstracts (1999)

Solid phase extraction : An alternative to the use of rotary evaporators for solvent removal in the rapid formulation of PET radiopharmaceuticals

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42(1), 63-75

Solid phase extraction (SPE) was used for the formulation of several radiopharmaceuticals. The method involves dilution of the previously purified HPLC compound with water, trapping of the activity on an ... [more ▼]

Solid phase extraction (SPE) was used for the formulation of several radiopharmaceuticals. The method involves dilution of the previously purified HPLC compound with water, trapping of the activity on an SPE bed, washing off the support, elution of the radiopharmaceutical with a small volume of ethanol (<1 mL) and dilution with sterile isotonic saline solution. Recovery of the radiopharmaceuticals was always higher than 97%. Two different methods of automation were developed for the formulation of [11C] and [18F]radiopharmaceuticals. In all cases, organic solvent levels in the injectable solution were below the recommended limits. This fast (3-6 min.) and easy to automate process can be considered as an alternative to the conventional methods (rotary evaporators). Copyright © 1999 John Wiley [less ▲]

High-yield radiosynthesis and preliminary in vivo evaluation of p-[18F]MPPF, a fluoro analog of WAY-100635.

in Nuclear Medicine & Biology (1998), 25(4), 343-50

No-carrier-added 4-[18F]fluoro-N-[2-[1-(2-methoxyphenyl)-1 piperazinyl]ethyl-N-2-pyridinyl-benzamide (p-[18F]MPPF) was synthesized by nucleophilic substitution of the corresponding nitro compound in the ... [more ▼]

No-carrier-added 4-[18F]fluoro-N-[2-[1-(2-methoxyphenyl)-1 piperazinyl]ethyl-N-2-pyridinyl-benzamide (p-[18F]MPPF) was synthesized by nucleophilic substitution of the corresponding nitro compound in the presence of Kryptofix 222 and K2CO3 by microwave heating (3 min, 500 W) using a remotely controlled radiosynthesis. Baseline separation of p-[18F]MPPF from the nitro derivative was performed on a semipreparative HPLC C18 column. After Sep-Pak formulation, the radiopharmaceutical was obtained with a radiochemical yield of 25% (EOS) in about 70 min. Specific radioactivity averaged between 1-5 Ci/micromol EOS. Labelling of the ortho and meta derivatives was also attempted. Brain uptake of p-[18F]MPPF was studied with PET on fluothane-anesthetized cats. Following intravenous injection of p-[18F]MPPF, high accumulation of radioactivity was observed in the hippocampus and cerebral cortex. Low levels of radioactivity were observed in cerebellum. At 30 min, the mean hippocampus/cerebellum and cortex/cerebellum ratios were 5 and 3.8, respectively. The accumulation of the tracer was blocked by prior administration of reference WAY-100635, demonstrating the specificity of the ligand. [less ▲]

Métabolisme de la 6-fluoro-L-tyrosine chez le rat

Poster (1997, May 29)

Le p-[18F]MPPF: un nouveau ligand pour l'étude par TEP des récepteurs 5-HT1A

Poster (1997, May 25)

Synthesis of a fluorinated analogue of L-threo-3-(3,4-dihydroxyphenyl)serine: 6-fluoro-L-threo-DOPS.

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

Metabolism of no carrier added 2-[18F]fluoro-L-tyrosine in free moving rats.

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

High yield radiosynthesis of p-[F-18]MPPF, 5-HT1A antagonist, and PET studies in cat brain.

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1997), 38

Evaluation of p-[F-18]MPPF, 5-HT1A antagonist, in rats: tissue distribution, autoradiography and metabolism.

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1997), 38

Enantioselective syntheses of no-carrier-added (nca) (S)-4-chloro-2 F-18 fluorophenylalanine and (S)-(alpha-methyl)-4-chloro-2 F-18 fluorophenylalanine

in Journal of Fluorine Chemistry (1996), 80(2), 117-124

(S)-4-Chloro-2-fluorophenylalanine and (S)-( a-methyl)-4-chloro-2-fluorophenylalanine were synthesized and labeled with no carrier added (n.c.a.) fluorine-18 through a radiochemical synthesis relying on ... [more ▼]

(S)-4-Chloro-2-fluorophenylalanine and (S)-( a-methyl)-4-chloro-2-fluorophenylalanine were synthesized and labeled with no carrier added (n.c.a.) fluorine-18 through a radiochemical synthesis relying on the highly enantioselective reaction between 4-chloro-2-[18F] fluorobenzyl iodide and the lithium enolate of (2s) -1-( tert-butyloxycarbonyl) -2-( tert-butyl)-3-methyl- 1,3-imidazolidine-4-one for (S) -4-chloro-2- [18F] fluorophenylalanine and (2S,5S)-1-( tert-butyloxycarbonyl) -2-( tert-butyl) -3,5-dimethyl- 1,3-imidazolidine-4-one for (S) -( a-methyl) -4-chloro-2- [18F] fluorophenylalanine. Quantities of about 20-25 mCi were obtained at the end of synthesis, ready for injection after hydrolysis and high performance liquid chromatography (HPLC) purification, with a radiochemical yield of 17%-20% corrected to the end of bombardment after a total synthesis time of 90-105 min from [18F] fluoride. The enantiomeric excesses were shown to be 97% or more for both molecules without chiral separation and the radiochemical and chemical purities were 98% or better. [less ▲]