Dl-Tryptophan → N-(3-acetoxy-4-methoxycarbonylbenzyl)-3-(3-indolyl)propanamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Ethyl trifluoroacetate (1.7 mL) was added to a stirred solution of DL-tryptophan (2.3 g) and triethylamine (1.6 mL) in DMF (5 mL), then the flask was sealed and purged with nitrogen, and the mixture stirred at 20° C. for 1 day (method of Curphey T. J., J. Org. Chem. 1979;44:2805). Excess reagents were removed under vacuum, then triethylamine (1.9 mL) and DMF (10 mL) were added, and the mixture cooled to 0° C. DEPC (98%, 2.0 mL) was added, followed by benzylamine (1.72 mL), then the mixture was stirred under nitrogen at 20° C. for 1 day. The resulting solution was diluted with water (100 mL) and extracted with EtOAc (3×100 mL). Evaporation gave an oil which was purified by chromatography on silica gel, eluting with EtOAc:light petroleum (1:1), to give DL-N-benzyl-α-trifluoroacetylamino-3-(3-indolyl) propanamide [II: R1 =R3 =H, R2 =CH2CH(NHCOCF3)CONHCH2Ph] (2.21 g, 50%); mp (EtOAc/light petroleum) 181°-183° C.

Herkunft & Nachweise