Synthetic peptides having pituitary growth hormone releasing activity

Abstract

Novel peptides having the following amino acid sequence ##STR1## wherein X.sub.1, X.sub.2, and X.sub.3 are selected from a group consisting of N-terminal and desamino alpha-carbon substitutions and a and b are 0 or 1, provided that a and b are always 0 when A.sub.1 is a desamino residue; A.sub.1 and A.sub.4 are selected from a group consisting of histidyl, arginyl, lysyl, .alpha.-naphthylalanyl, .beta.-naphthylalanyl, isoquinolyl, tyrosyl, tryptophyl, phenylalanyl, homologues and analogues thereof, and, with respect to A.sub.1 only the desamino forms thereof; A.sub.2 and A.sub.5 are selected from a group consisting of D-histidyl, D-arginyl, D-lysyl, D-.alpha.-naphthylalanyl, D-.beta.-naphthylalanyl, D-isoquinolyl, D-tyrosyl, D-tryptophyl, D-phenylalanyl, homologues and analogues thereof; A.sub.3 is selected from a group consisting of glycyl, alanyl, valyl, leucyl, isoleucyl, prolyl, seryl, threonyl, methionyl, aspartyl, glutamyl, asparginyl, glutaminyl, histidyl, D-alanyl, D-valyl, D-leucyl, D-isoleucyl, D-prolyl, D-seryl, D-threonyl, D-methionyl, D-aspartyl, D-glutamyl, D-asparaginyl, D-glutaminyl, D-histidyl, and homologues and analogues thereof; A.sub.6 is selected from a group consisting of amino acids of the L- and D- configuration, homologues and analogues thereof, and the descarboxy forms thereof; and Y is selected from a group consisting of C-terminal and descarboxy alpha-carbon substitutions; and the pharmaceutically acceptable salts thereof.

Dependencies are inferred from the claim text.