Oligopeptide compounds containing D-2-alkyltryptophan capable of promoting the release of growth hormone

摘要

A peptide of formula:A-D-X-D-Mrp-B(I)A-D-X-D- beta Nal-B(II)E-D-X-Mrp-NH2(III)wherein A is hydrogen, 2-aminoisobutyryl, or 4-aminobutyryl; D relates to the dextro isomer; X is Mrp, wherein Mrp is a 2-alkyltryptophan of formula (IV): wherein R is hydrogen, CHO, SO2CH3, mesitylene-2-sulfonyl, PO3(CH3)2, PO3H2, wherein R1 is a C1-C3 alkyl group, or wherein X is a residue of protected serine, Ser (Y), wherein Y is benzyl, p-chlorobenzyl, 4-methoxybenzyl, 2,4,6-trimethoxybenzyl, or tert-butyl; B is NR2R3, wherein R2 and R3, may be the same or different, are hydrogen, a C1-C3 alkyl group, an OR4 group, wherein R4 is hydrogen, a C1-C3 alkyl group or the C-Lys-NH2 group, wherein C is Phe, Mrp or D-Mrp; E is hydrogen, GAB or D-Mrp, and addition salts with pharmaceutically acceptable organic or inorganic acids of the peptide.