Peptide derivatives and medicinal compositions

摘要

An object of the present invention is to provide a novel nociceptin receptor agonist. The present invention relates to a peptide derivative represented by the following general formula (1): (in which A represents alkylene, -(CH2)nCO- or a group represented by the following formula (2) or (3): wherein n represents an integer of 1 to 8; X and Y are same or different and each represents -CONH- or -CH2NH-; R<1>, R<2> and R<3> are same or different and each represents alkyl, aryl or heteroaryl; Z represents -CON(R<4>)R<5> or -CH2N(R<4>)R<5>; and R<4> and R<5> are same or different and each represents hydrogen, alkyl, aryl or heteroaryl) or a pharmaceutically acceptable salt thereof. A pharmaceutical composition according to the present invention is useful as a nociceptin receptor agonist.