In pursuit of α4β2 nicotinic receptor partial agonists for smoking cessation:: Carbon analogs of (-)-cytisine

The preparation and biological activity of analogs of (-)-cytisine, an alpha 4 beta 2 nicotinic receptor partial agonist, are discussed. All-carbon-containing phenyl ring replacements of the pyridone ring system, generated via Heck cyclization protocols, exhibited weaker affinity and lower efficacy partial agonist profiles relative to (-)-cytisine. In vivo, selected compounds exhibit lower efficacy partial agonist profiles than that of (-)-cytisine. (c) 2005 Elsevier Ltd. All rights reserved.