Structure-activity relationships analysis of thienorphine and its derivatives

Thienorphine is a chemically-new opioid developed in Beijing Institute of Pharmacology and Toxicology.  To elucidate the chemical basis for the unique pharmacological effects of thienorphine, 15 derivatives were synthesized according to combinatorial chemistry and the structure-activity relationships of these compounds were studied.  It is demonstrated that thienorphine is a potent long-acting partial agonist.  N-Cyclopropylmethyl is responsible for the antagonist effect of thienorphine.  More importantly, thiophene at the end of side chain is most likely the pharmacophore accounts for the long-lasting effect of thienorphine.  Change of the connection of thiophene and the side chain does not result in changes in the antinociceptive activity.