Synthesis of epibatidine isomers: endo-5- and 6- (6′-chloro-3′-pyridyl-2-azabicyclo[2.2.1]heptanes

Synthesis of the title compounds is described; detailed NMR data are provided in support of the proposed stereostructures. The 5- and 6-endo-compounds show high selectivity for α4β2 versus α7 nAChR subtypes; in contrast, the exo-stereoisomers show comparatively weak affinity at both subtypes.