The molecule is a withanolide that is 22,26-epoxyergosta-1,4-diene substituted by an acetyloxy group at position 18 and oxo groups at positions 3 and 26. Isolated from a Formosan soft coral Paraminabea acronocephala, it has been found to inhibit the accumulation of the pro-inflammatory iNOS protein. It has a role as a coral metabolite and an EC 1.14.13.39 (nitric oxide synthase) inhibitor. It is a delta-lactone, an acetate ester, an ergostanoid, a withanolide, a steroid ester and a 3-oxo-Delta(1),Delta(4)-steroid.
[(8R,9S,10R,13R,14S,17R)-17-[(1S)-1-[(2R,4S,5S)-4,5-dimethyl-6-oxooxan-2-yl]ethyl]-10-methyl-3-oxo-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-13-yl]methyl acetate