Total Syntheses of (-)-Transtaganolide A, (+)-Transtaganolide B, (+)-Transtaganolide C, and (-)-Transtaganolide D and Biosynthetic Implications

摘要

‘Dibal'lin’ on a budget: The enantioselective total syntheses of transtaganolides A–D are rapidly achieved by a highly diastereoselective Ireland–Claisen/Diels–Alder cascade reaction of an enantioenriched geraniol derivative (see scheme). Based on X-ray diffraction data, the absolute configuration of these metabolites is established and discussed within the context of existing biosynthetic hypotheses.