Steroids constituents from the soft coral Cladiella krempfi

From the soft coral Cladiella krempfi collected from the inner reef of Hainan Island,the South China Sea,12 compounds,named 1,2-[1',3',4']oxodithiin-pregna-20-en-3-one(1);19-nor-4-methylpregna-1,3,5(10),20-tetraen-1-ol(2);pregna-1-en-3-one-20-ol(3);pregna-1,7-dien-20-ol-3-one(4);Pregna-5,20-dien-3-O-α-fucopyranoside(5);Pregna-20-en-3-O-α-fucopyranoiside(6);pregna-1,20-dien-3-one(7);1,4,20-pregnatien-3-one(8);24-methyl-5α-cholesta-7,22-diene-3β,5,6β-triol(9);26-methyl-24-methylenecholest-5-en-3β-ol(10);Cholesta-5-en-3β-ol(11);β-sitosterol(12)were isolated.Their structures were identified by1H and 13C NMR,2D NMR,MS spectral analysis and in comparison of the spectral data with those reported in literatures.Compounds 1~6 were isolated from the genus Cladiella for the first time.In addition,the plausible biogenetic paths for compounds were also discussed.