Synthesis and Absolute Configuration of Neocnidilide

Abstract

(-)-Neocnidilide (1), an antifungal substance isolated from Cnidium officinale Makino and its antipode 11 were respectively synthesized from (S)- and (R)-(E)- 1-ethenylpentyl 2, 4-pentadienoate (4) and (5) via the intramolecular Diels-Alder reaction. This synthesis established that the absolute configuration of 1 was 3S, 3aR.