[2-Methyl-Ala6 ]LRH

Claim 1

A compound selected from the group consisting of L-p-Glu-L-His-L-Trp-L-Ser-L-Tyr-2-methyl-Ala-L-Leu-L-Arg-L-Pro-Gly-NH.sub.2 and L-p-Glu-L-His(N im -R 4 )-L-Trp-L-Ser(R 3 )-L-Tyr(R 2 )-2-methyl-Ala-L-Leu-L-Arg(N.sup.g -R 1 )-L-Pro-Gly-R and non-toxic salts thereof; wherein; R is a member selected from the group consisting of --NH 2 ,--OH, --O(lower)alkyl of 1 to 6 carbon atoms, --O--benzyl, ##SPC1## and --OHC 2 --(polystyrene support resin); R 1 is a member selected from the group consisting of --H and a protecting group for the N.sup.δ, N.sup.ω and N.sup.ω ' nitrogen atoms of arginine selected from nitro, tosyl, benzyloxycarbonyl, adamantyloxycarbonyl and tert-butyloxycarbonyl; R 2 is selected from the class consisting of hydrogen and a protecting group for the phenolic hydroxyl group of tyrosine selected from tert-butyl, tetrahydropyranyl, trityl, benzyl, 2,6-dichlorobenzyl, benzyloxycarbonyl and 4-bromobenzyloxycarbonyl; R 3 is selected from the class consisting of hydrogen and a protecting group for the alcoholic hydroxyl group of serine and is selected from acetyl, benzoyl, tetrahydropyranyl, tert-butyl, trityl, 2,6-dichlorobenzyl, benzyl and benzyloxycarbonyl; and R 4 is selected from the group consisting of hydrogen and a protecting group for the imidazole nitrogen atom of histidine selected from tosyl, benzyl, trityl, 2,4-dinitrothiophenyl, 2,2,2-trifluoro-L-benzyloxycarbonylaminoethyl and 2,2,2-trifluoro-L-butyloxycarbonylaminoethyl.