Abstract:
The isolation of bioactive polyether compounds from the methanol extract of Thai marine sponge, Biemna fortis was guided by both tumor cytotoxicity and 1H-NMR signals. Moreover, three diene-unsaturated steroid compounds, brassicasterol, cerevisterol and 22(E)-ergosta-7, 22-dien-3, 5-diol-6-one, were isolated from the same extract. The identification and structure elucidation of the isolated steroids were achieved by analyses of the UV, IR, MS, ID and 20-NMR spectral data.