Further Synthesis of Enkephalinol Analogs containing the Dipeptide Unit Tyr-Arg (Kyotorphin)

Abstract

In order to obtain enkephalin derivatives with high analgesic activity, four enkephalinol analogs having the Tyr-D-Arg unit in the N-terminal position were synthesized. Of these, H-Tyr-D-Arg-Gly-MePhe-Met (O)-ol exhibited analgesic activity comparable to that of morphine after intravenous administration to mice.