Synthesis, nicotinic acetylcholine receptor binding, in vitro and in vivo pharmacology properties of 3 '-(substituted pyridinyl)-deschloroepibatidine analogs

摘要

Over the last several years we have synthesized and studied the in vitro and in vivo nAChR pharmacological properties of epibatidine (4) analogs. In this study we report the synthesis, nAChR in vitro and in vivo pharmacological properties of 3'-(substituted pyridinyl)-deschloroepibatidine analogs (5a-e and 6a-e). All of the analogs had high binding affinity for alpha 4 beta 2*-nAChRs. Several of the analogs were potent antagonists of alpha 4 beta 2-nAChRs in in vitro efficacy tests and were potent antagonists of nicotine-induced antinociception in the mouse tail-flick test. Compound 6b had a K-i = 0.13 nM in the binding assay, 25- and 46-fold selectivity for the alpha 4 beta 2*-nAChR relative to the alpha 3 beta 4- and alpha 7-nAChR, respectively, in the in vitro efficacy test and an AD(50) = 0.13 mu g/kg in the tail-flick test. Combined with favorable calculated physiochemical properties compared to varenicline, our findings suggest that 6b should be considered for development as a potential pharmacotherapy for treating nicotine addiction and other CNS disorders. (C) 2015 Elsevier Ltd. All rights reserved.