Patent ID: 6953780

Claim:
A compound of formula I or a stereoisomer thereof: RCO-A-B—C—OH (I) wherein R is hexamethyleneiminyl or Phenoxy-, or RCO-A is the following structure: A is Pro, Gly or an aliphatic amino acid; B is D-Trp, D-Pya, or D-Phe, said D-Phe having a phenyl group, wherein position 2, 3, 4 or 5 of said phenyl group is optionally substituted by one or two members selected from the group consisting of halogen, nitro, carboxyl, and (C1-C4)-alkyl; C is D-Trp, D-Pya, or D-Phe, said D-Phe having a phenyl group, wherein position 2, 3, 4 or 5 of said phenyl group is optionally substituted by one or two members selected from the group consisting of halogen, nitro, carboxyl, and (C1-C4)-alkyl; with the proviso that at least one of B and C is D-Trp, and with the proviso that when A is Gly, then R is hexamethyleneiminyl, B is D-Trp and C is D-Trp, and with the proviso that when R is hexamethyleneiminyl or phenoxy, and A is Leu, and B is D-Trp, then C is D-Pya or D-Phe, said D-Phe being substituted at position 2, 3, 4 or 5 of the phenyl group by one or two members selected from the group consisting of halogen, nitro, carboxyl and (C 1 -C 4 )-alkyl.