PHARMACOLOGICALLY ACTIVE PEPTIDES, THEIR PREPARATION AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM

摘要

Compounds of the formula and pharmaceutically acceptable non-toxic acid addition salts thereof, in which L and D define the chirality; R1 is hydrogen or C1-C3 primary alkyl; R2 is C1-C4 primary or secondary alkyl, allyl, cyclopropylmethyl, C1-C2 hydroxyalkyl, or -(CH2)m-U-CH3 in which U is -S- or >S-O and m is 1 or 2; R3 is hydrogen, C1-C4 primary or secondary alkyl, cyclopropylmethyl, or allyl; R4 is hydrogen, C1-C5 primary or secondary alkyl, -(CH2)n-X-(CH2)p-CH3 in which X is -O-, -S-, >S-O or n is 1 or 2, and p is 0 or 1, phenyl, or monosubstituted phenyl in which the substituent is halo, hydroxy, C1-C3 alkoxy, nitro, C1-C3 alkyl, or trifluoromethyl; R5 is hydrogen or C1-C4 primary alkyl; and Z is -CH2OR6, in which R6 is hydrogen or C1-C3 alkyl and R7 is C1-C3 alkyl; subject to the proviso that one but not both of R3 and R5 is other than hydrogen; are useful analgesic agents.