Patent ID: 7384979

Claim:
A pharmaceutical composition comprising a compound of the formula: wherein: R 1 is H or C 1-5 alkyl; R 2 is H, phenoxy, benzyl, substituted phenoxy (where the substituents are selected from C 1-5 alkyl, C 1-5 alkoxy, hydroxy, halo, trifluoromethyl, nitro, cyano, and amino), or CO 2 Me; R 3 is H, phenyl, triflouromethyl; and R 4 is the side chain of a natural or unnatural α-amino acid, where if said side chain contains a protectable group, that group may be protected with a member of the group consisting of succinyl, glutaryl, 3,3-dimethylglutaryl, C 1-5 alkyl, C 1-5 alkoxycarbonyl, acetyl, N-(9-flourenylmethoxycarbonyl), trifluoroacetyl, omega-carboxyC 1-5 alkylcarbonyl, t-butoxycarbonyl, benzyl, benzyloxycarbonyl, 2-chlorobenzyloxycarbonyl, phenylsulfonyl, ureido, t-butyl, cinnamoyl, trityl, 4-methyltrityl, 1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl, tosyl, 4-methoxy-2,3,6-trimethylbenzenesulfonyl, phenylureido, and substituted phenylureido(where the phenyl substituents are phenoxy, halo, C 1-5 alkoxycarbonyl).