Octahydropyrrolo[3,4-c]pyrrole: A Diamine Scaffold for Construction of Either α4β2 or α7-Selective Nicotinic Acetylcholine Receptor (nAChR) Ligands. Substitutions that Switch Subtype Selectivity

A series of 5-(pyridine-3-yl)octahydropyrrolo[3,4-c]pyrroles have been prepared that exhibit high affinity to alpha 4 beta 2 and/or alpha 7 nicotinic acetylcholine receptors (nAChRs). Simple substitution patterns have been identified that allow construction of ligands that are highly selective for either nAChR subtype. The effects of substitution on subtype selectivity provide some insight into the differences in the ligand binding domains of the alpha 4 beta 2 and alpha 7 receptors, especially in regions removed from the cation binding pocket.