Total Synthesis of Jujuyane

Abstract

Oxidopyrylium ylide, which can be prepared from furfuryl alcohol, readily dimerizes in the regio- and stereoselective manner generating doubly bridged carbocycle.[1] Although this dimer is a potential precursor of highly functionalized cyclooctanoids, its application to natural product synthesis has never been reported until today.[2] We accomplished the first total synthesis of Jujuyane, a sesquiterpene lactone isolated from Stevia jujuyansis,[3] utilizing oxidopyrylium dimerization reaction. Stereocenters around a core 8-membered ring structure could be settled by substrate-controlled reactions on the oxa-bridged synthetic intermediate. Subsequent oxa-bridge opening and functional group manipulation completed the total synthesis of Jujuyane. References [1] Hendrickson, J. B.; Farina, J. S. J. Org. Chem., 1980, 45, 3361-3363. [2] Krishna, U. M.; Deodhar, K. D.; Trivedi, G. K.; Mobin, S. M., J. Org. Chem., 2004, 69(3), 967-969 [3] Gil, R. R.; Pacciaroni, A. D. V.; Oberti J. C.; Diaz, J. G.; Herz, W. Phytochemistry, 1992, 31(2), 593-596