5′-O-methyl-14-hydroxyarmillane, a new armillane-type sesquiterpene from cultures of Guyanagaster necrorhiza

Abstract Protoilludene-type sesquiterpene aryl esters are a unique and very diverse compound class that were exclusively isolated from members of the genus Armillaria ( Agaricomycetes , Physalacriaceae ) up to this point. Herein, we describe isolation structural characterization 5′- O -methyl-14-hydroxyarmillane 1 ), new armillane-type derivative, was obtained submerged cultures Guyanagaster necrorhiza (CBS 138623) together with known congeners melleolide G 2 B 3 10-dehydroxy-melleolide 4 ). ROESY data coupling constants assigned relative configurations while common absolute confirmed comparison its ECD spectrum one 10-hydroxy-5′-methoxy-6′-chloroarmillane 5 Additionally, configuration revised based on observed correlations. It is first time protoilludene-type another genus, namely, closely related . – evaluated for their biological activities in serial dilution assay against several yeast, fungi, bacteria, as well cytotoxicity different cell lines. Compound moderately active Bacillus subtilis Staphylococcus aureus Mucor hiemalis Furthermore, showed weak cytotoxic effects mouse fibroblast line L929 cervix carcinoma KB3.1.