Steroids from the South China Sea Gorgonian Coral Muricella flexuosa

Four new steroidal glycosides and a new steriod linked with a 4-hydroxyphenylmethylene group, namely muricellasteroids A-E (1-5), together with one known steroidal glycoside analog, 22 alpha,2',3',4'-O-tetraacetyl-27-O-[beta-D-arabino-pyranosyl-oxy]-20 beta-hydroxy-cholest-4-ene-3-one (6), were isolated from the EtOH/CH(2)Cl(2) extracts of the South China Sea gorgonian coral Muricella flexuosa. The structures of 1-5 were established by means of ID- and 2D-NMR and other spectroscopic analyses. Compounds 1-3 and 5-6 showed moderate cytotoxicity against A375, K562, and A549 cancer cell lines.