Radiosynthesis of 4-[ 18 F]fluoro- l -tryptophan by isotopic exchange on carbonyl-activated precursors
摘要:
Several F-18-labeled aromatic amino acids have been developed primarily for tumor imaging with positron-emission-tomography (PET). Also, F-18-labeled tryptophan derivatives were synthesized by electrophilic F-18-fluorination or by introducing a [F-18]fluoroalkyl group. Here, a 3-step method for a nucleophilic radiosynthesis of 4-[1(8F)]fluoro-L-tryptophan was developed. A carbonyl activated precursor containing a chiral amino acid building block was radiofluorinated by isotopic exchange, followed by removal of the activating formyl group by reductive decarbonylation and subsequent cleavage of the building block under acidic conditions. The title compound was obtained within 100 min with a radiochemical yield of about 13%, a molar activity of >70 MBq/mmol and an enantiomeric excess of >99%. (C) 2015 Elsevier Ltd. All rights reserved.
Radiosynthesis of 4-[ 18 F]fluoro- l -tryptophan by isotopic exchange on carbonyl-activated precursors
摘要:
Several F-18-labeled aromatic amino acids have been developed primarily for tumor imaging with positron-emission-tomography (PET). Also, F-18-labeled tryptophan derivatives were synthesized by electrophilic F-18-fluorination or by introducing a [F-18]fluoroalkyl group. Here, a 3-step method for a nucleophilic radiosynthesis of 4-[1(8F)]fluoro-L-tryptophan was developed. A carbonyl activated precursor containing a chiral amino acid building block was radiofluorinated by isotopic exchange, followed by removal of the activating formyl group by reductive decarbonylation and subsequent cleavage of the building block under acidic conditions. The title compound was obtained within 100 min with a radiochemical yield of about 13%, a molar activity of >70 MBq/mmol and an enantiomeric excess of >99%. (C) 2015 Elsevier Ltd. All rights reserved.
[EN] NOVEL COMPOUNDS EFFECTIVE AS XANTHINE OXIDASE INHIBITORS, METHOD FOR PREPARING THE SAME, AND PHARMACEUTICAL COMPOSITION CONTAINING THE SAME<br/>[FR] NOUVEAUX COMPOSÉS EFFICACES EN TANT QU'INHIBITEURS DE XANTHINE OXYDASE, LEUR PROCÉDÉ DE PRÉPARATION ET COMPOSITION PHARMACEUTIQUE LES CONTENANT