SECONDARY MOLD METABOLITES .47. ISOLATION AND STRUCTURE ELUCIDATION OF CLAVILACTONES AC, NEW METABOLITES FROM THE FUNGUS CLITOCYBE CLAVIPES

Clavilactones A-C (1, 4 and 5) have been isolated from cultures of the Basidiomycetous fungus Clitocybe clavipes. Their structures and relative configurations have been deduced from H-1 and C-13 NMR studies, chemical reactions and single-crystal X-ray analysis of the dimethyl ether derivative 3. H-1-H-1 coupling constants, NOE data and molecular modelling calculations all-suggest that the molecules have little conformational mobility and the conformation adopted in solution by clavilactone A 1 and dimethyl ether derivative 3 is essentially identical with that of 3 in the solid state. Clavilactones A-C exhibit antifungal and antibacterial activity and inhibit the growth germination of Lepidium sativum. A possible biogenetic origin of clavilactone A 1 is discussed.