PEPTIDE DERIVATIVES

摘要

RAN 4105/32 A process for the manufacture of peptide derivatives of the general formula (I) , wherein R1, R2 and R3 each represent the characterising group of an .alpha.-amino acid of the type normally found in proteins; R4 represents a hydroxy or methyl group; n stands for zero, 1, 2 or 3; the configuration at the carbon atoms designated as (a), (b) and (c) is L (when R1 or R2 ? H); and the configuration at the carbon atom designated as (d) is (R) (when R3 ? H), and of pharmaceutically acceptable salts thereof, which process comprises condensing a compound of the general formula (II) , wherein R10, R20 and R30 have any of the values accorded to R1, R2 and R3 above respectively except that any amino group(s) present is (are) protected by a hydrogenolytically cleavable protecting group, R4 and n have the significances given above and the configuration at the carbon atoms designated as (b), (c) and (d) is as spedified above, with a compound of the general formula (III) , wherein R5 represents a 2,4,5-trichloro-phenyl, pentachlorophenyl or succinimido group, R6 represents a hydrogen atom or an aralkoxycarbonyl group and the coniiguration at the carbon atom designated as (a) is L, subjecting a condensation product obtained which contains a protected amino group and/or an aralkoxycarbonyl group R6 to hydrogenoiysis and, if desired, converting a compound of formula I obtained into a pharmaceutically acceptable salt.