Cleistenolide and Cleistodienol: Novel Bioactive Constituents of Cleistochlamys kirkii

Abstract

(-)-5-Acetoxy-6-(1-benzoyloxy-2-acetoxyethyl)-pyr-3-en-2-one (cleistenolide) and (-)-2,6-diacetoxy-5-hydroxy-cyclohex-3-enylidenemethyl benzoate (cleistodienol) were isolated as novel antimicrobial and cytotoxic constituents of Cleistochlamys kirkii (Annonaceae), together with ( Z)-(+)-5-(2,3-dihydroxy-propylidene)-5 H-furan-2-one and its acetyl and benzoyl derivatives, (-)-1,6-desoxy-β-senepoxide, pinocembrin and polycarpol. Structural determination was achieved based on spectroscopic and other physical data. The structure of cleistenolide was confirmed by single crystal X-ray crystallographic analysis.