The family of aspidosperma alkaloids is a subclass of monoterpene indole alkaloids with a fascinating diversity in its pentacyclic skeleton.[1] The potent biological activity of many members of this family as well as their structural challenges has made them highly interesting targets for synthetic studies and total synthesis over several decades. Recently, we reported a synthetic strategy for the synthesis and dimerization of aspidosperma alkaloids.[2]  We now describe a new synthetic route to these alkaloids employing a key spirocyclization step with outstanding levels of diastereoselectivity and dramatically enhanced overall efficiency.  The application of this new synthetic approach to several alkaloids with various substitution patterns on the D-ring along with detailed conformational analysis of intermediates and discussion of stereoelectronic factors responsible for the enhanced efficiency will be presented.[1] Saxton, J. E. The Alkaloids, Chem. Biol. 1998 , 51, 1�197.  [2] a) Medley, J. W.; Movassaghi, M. Angew. Chem. Int. Ed. 2012 , 51, 4572�4576. b) Medley, J. W.; Movassaghi, M. Org. Lett. 2013 , 15, 3614�3617.

Concise and enantioselective total synthesis of aspidosperma alkaloids

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.