Total Synthesis of the Proposed Structures of the Novel Antimalarial Pyranone Cryptorigidifoliol E

Abstract

The total syntheses of the proposed structures of the antimalarial lactone cryptorigidifoliol E are described. The synthetic sequence notably features a Bartlett–Smith halocyclization to give a chiral epoxide, followed by its regioselective ring-opening reaction, Still–Gennari­ olefination, Corey–Bakshi–Shibata (CBS) ynone reduction, and olefin cross-metathesis.

Key words

total synthesis - cryptorigidifoliol E - lactones - Bartlett–Smith halocyclization - Corey–Bakshi–Shibata reduction - cross-meta­thesis

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