Synthesis, nicotinic acetylcholine receptor binding, and antinociceptive properties of 2'-fluoro-3'-(substituted pyridinyl)-7-deschloroepibatidine analogues.

2'-Fluoro-3-(substituted pyridine)epibatidine analogues 7a-e and 8a-e were synthesized, and their in vitro and in vivo nAChR properties were determined. 2'-Fluoro-3'-(4″-pyridinyl)deschloroepibatidine (7a) and 2'-fluoro-3'-(3″-pyridinyl)deschloroepibatidine (8a) were synthesized as bioisosteres of the 4'-nitrophenyl lead compounds 5a and 5g. Comparison of the in vitro nAChR properties of 7a and 8a to those of 5a and 5g showed that 7a and 8a had in vitro nAChR properties similar to those of 5a and 5g but both were more selective for the α4β2-nAChR relative to the α3β4- and α7-nAChRs than 5a and 5g.