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Published on: September 20, 2016
Novel delta opioid receptor agonists with oxazatricyclodecane structure showing potent agonistic activities
Kohei Hayashida1, Shigeto Hirayama2, Takashi Iwai3
1Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan; Discovery Research Laboratories, Nippon Chemiphar Co., Ltd., 1-22, Hikokawado, Misato, Saitama 341-0005, Japan.
Abstract:
We recently reported oxazatricyclodecane derivatives 1 as δ opioid receptor (DOR) agonists having a novel chemotype, but their DOR agonistic activities were relatively low. Based on the working hypothesis that the dioxamethylene moiety in 1 may be an accessory site and that it may interfere with the sufficient conformational change of the receptor required for exerting the full agonistic responses, we designed and synthesized new oxazatricyclodecane derivatives 2-4 lacking the dioxamethylene moiety. As we expected, the designed compounds 2-4 showed pronouncedly improved agonistic activities for the DOR. Compound 2a with the 17-cyclopropylmethyl substituent was a potent agonist with the highest selectivity for the DOR and was expected to be a lead compound for novel and selective DOR agonists.
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