| Definition: |
An organic heterotetracyclic compound that is isopimarane in which a hydrogen at position 2 of the 13-ethyl substituent has been replaced by a (sulfooxy) group, a double bond has been introduced at the 7-8 position, and the beta-methyl group at position 4 has been oxidised to the corrsponding carboxy group and coupled to position 6 to give a gamma-lactone. Isolated from an avendophytic fungus, Xylaria sp. YM 311647, obtained from Azadirachta indica, it shows potent inhibitory activity against C. albicans and Pyricularia oryzae. |