ESTERS OF TRI- AND TETRAPEPTIDES, INHIBITORS OF GASTRIC SECRETION, PREPARATION PROCESS AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM

摘要

The invention relates to the peptides of the formula: (I) in which: R represents hydrogen or a protecting group for the terminal amine group, such as t-butoxycarbonyl (Boc), benzyloxycarbonyl (Z) or lower alkanoyl; X1 represents either beta-Ala or a direct bond between R and the terminal amine group of the amino acid TRP; TRP denotes either the L isomer or the D isomer of tryptophan; X2 represents L-leucine, L-methionine or L-norleucine; and Y denotes hydrogen, a halogen atom (preferably fluorine or chlorine), a trifluoromethyl group, a cyano group or a nitro group. These peptides inhibit gastric secretion.