Benzyloxycarbonyl-asparagine → N-[3(S)-[[N-(benzyloxycarbonyl)-L-asparaginyl]amino]-4-(4-fluorophenyl)-2(R)-hydroxybutyl]-L-proline tert.butyl ester

Participants

Reaction Steps

A solution of 270 mg of N-[3(S)-(benzyloxyformamido)-4-(4-fluorophenyl)-2(R)-hydroxybutyl]-L-proline tert.butyl ester in 50 ml of ethanol was hydrogenated over 30 mg of 10% palladium-on-carbon for 2 hours. The catalyst was removed by filtration and the filtrate was evaporated to give an oil which was coupled with 158 mg of N-(benzyloxycarbonyl)-L-asparagine in a manner analogous to that described in Example 1. The crude product was chromatographed on silica gel using 10% methanol in dichloromethane for the elution. There were obtained 120 mg of N-[3(S)-[[N-(benzyloxycarbonyl)-L-asparaginyl]amino]-4-(4-fluorophenyl)-2(R)-hydroxybutyl]-L-proline tert.butyl ester as a white solid of melting point 163°-164° C.

Provenance & Evidence