CYCLIC POLYPEPTIDES HAVING MU-RECEPTOR SPECIFICITY

摘要

Novel compounds which are capable of binding with enhanced specificity to the mu opioid receptor. The compounds are analogs of somatostatin and have formula (I) wherein: X is CONH2 or CH2OH; Y and Z are independently sulfur or CH2; R?1 and R2¿, which may be the same or different, are hydrogen, methyl, ethyl, cyclopentamethylene, or a lower alkyl group having five or less carbon atoms; R?3 and R4¿, which may be the same or different, are hydrogen, methyl, ethyl, cyclopentamethylene, or a lower alkyl group having five or less carbon atoms, provided, however, that R?1, R2, R3, and R4¿ may not all be hydrogen; AA¿1? is Phe, D-Phe, phenyl-Gly, D-Phenyl-Gly, Tyr, D-Tyr, L-1-Naphthylalanine, D-1-Naphthylalanine, or D-Phe(4-Me); AA2 is Tyr, Phe, Tyr(OMe), Phe(4-Me), Tyr(OEt), or Phe(4-Et); and AA3 is Lys, Arg, Orn or homo-Arg. The novel compounds have antagonist activity and may be used to induce pharmacological or therapeutic effects in humans and other animals.