Unified approach to miscellaneous Lycopodium alkaloids: Total synthesis of (+)-lyconadin A

ORGN 790

Scott P. West, spwest@berkeley.edu, Alakesh Bisai, Andrew D. Lim, Raja R. Narayan, and Richmond Sarpong. Department of Chemistry, University of California, Berkeley, 847 Latimer Hall, Berkeley, CA 94720
A unified approach to the ‘miscellaneous' subset of Lycopodium alkaloids has been developed. A key element is the elaboration of tricyclic cycloheptadiene 3 to form the common tetracyclic intermediate 2. Our strategy has been employed to achieve the enantioselective synthesis of the pentacyclic alkaloid (+)-lyconadin A (1). The key reaction involves an oxidative cyclization to form the crucial C-N bond to complete the pentacyclic core of the lyconadins. Studies on this novel transformation have been conducted to understand the mechanism of this process.