Patent ID: 8748564

Claim:
A compound represented by structural Formula I: wherein W and X are independently selected from CH 2 and S, but are not both CH 2 ; A is an amino acid selected from: alanine substituted on the side chain with a 5- or 6-membered heteroaromatic ring; and phenylalanine substituted on the phenyl ring with halogen, C 3-4 alkoxy, C 1-4 alkylhydroxy, or C 3-4 alkyl; B is an amino acid selected from: isoleucine; and glycine substituted on the α-carbon with C 4-6 cycloalkyl; C is an amino acid selected from: proline, optionally substituted on the side chain with hydroxyl, C 1-4 alkoxy, halogen or azide, and proline having its side chain optionally interrupted by a heteroatom and which optionally interrupted side chain is optionally substituted with C 1-4 alkyl; D is an amino acid selected from: leucine; homoleucine; isoleucine; and glycine substituted on the α-carbon with C 4-6 cycloalkyl; and E is an amino acid selected from: glycine and azaglycine, with the proviso that if C is 4-hydroxyproline, then A must be either phenylalanine substituted on the phenyl ring with halogen, or C 1-4 alkylhydroxy, and if C is 4-hydroxyproline and A is phenylalanine substituted on the phenyl ring with halogen, then either B or D must be glycine substituted on the α-carbon with C 4-6 cycloalkyl, or D must be isoleucine, with the further proviso that if A is phenylalanine substituted on the phenyl ring with C 1-4 alkyl or halogen, then C must be proline or proline substituted on the side chain with halogen, and with the further proviso that if A is phenylalanine substituted on the phenyl ring with halogen, then either B or D must be glycine substituted on the α-carbon with C 4-6 cycloalkyl, or D must be isoleucine.