D-2-alkyl-tryptophan and peptides containing same

Abstract

Peptides containing in its amino acid chain a D-2-alkylTryptophan residue wherein the alkyl group has between one and three carbon atoms and having pharmacological activity similar to that of analogous peptides containing natural unsubstituted D-Tryptophan residues in place of the D-2-alkylTryptophan. These new peptides are more resistant to oxidative degradation which usually takes place, for example, in the presence of reactive radicals or during high energy sterilization than unsubstituted Tryptophan containing peptides. Specific peptides include His-D-2-alkyl-Trp-Ala-Trp-D-Phe-Lys-NH.sub.2, Ala-His-D-2-alkyl-Trp-Ala-Trp-D-Phe-Lys-NH.sub.2, Pyro-Glu-His-Trp-Ser-Tyr-D-2-alkyl-Trp-Leu-Arg-Pro-Gly-NH.sub.2, Pyro-Glu-His-Ser-Tyr-D-2-alkyl-Trp-Leu-Arg-Pro-NHCH.sub.2 CH.sub.3, D-Pro-Gln-Gln-D-Trp-Phe-D-Trp-2-alkyl-Trp-Met-NH.sub.2, Arg-D-Trp-N-methyl-Phe-D-2-alkyl-Trp-Leu-Met-NH.sub.2, D-Phe-Cys-Phe-D-2-alkyl-Trp-Lys-Thr-Cys-NHCH(CH.sub.2 OH)CHOHCH.sub.3 and D-Phe-Cys-Tyr-D-2-alkyl-Trp-Lys-Val-Cys-Trp-NH.sub.2.

Dependencies are inferred from the claim text.