TETRAPEPTIDE DERIVATIVE, ITS PREPARATION AND ANALGESIC AGENT

摘要

NEW MATERIAL:The tetrapeptide derivative of formulaI(R1 is H or methyl; R2 is amino or lower alkyl) and its acid addition salt. EXAMPLE:H-Tyr-(D)-Met(O)-Gly-Etphe-NHNHCONH2. USE:An analgesic agent. It has strong activity to inhibit the gastroenteric movement, and is useful also as a remedy for gastorenteric disorder, such as diarrhea. It is also effective to mental diseases such as schizophrenia, etc. PROCESS:The objective compound of formulaIis prepared by catalytically reducing the compound of formula II (Y1 is protecting group; Y2 is H or protecting group) using a catalyst such as palladium black, thereby eliminating the protecting groups. The compound of formula II can be prepared by the condensation of partial amino acids which can constitute the polypeptide segment of the objective compound of formulaIor the peptide of said amino acids with a compound which can constitute the rest part of the objectve compound. The condensation is carried out by a peptide synthesizing means after protecting the carboxyl groups and amino groups which do not participate in the reaction.