Two new hydroperoxy steroids from the South China Sea gorgonian Rumphella sp.

Two new hydroperoxy steroids, namely, xidaosteroids A and B (1 and 2), along with five known related compounds 3-7, were isolated from the South China Sea gorgonian Rumphella sp.. Their structures were established by extensive spectroscopic analyses and comparison of the spectral data with those reported in the literature. In bioassay, compound 3 showed weak cytotoxicities against SNU-398 and Capan-1 cells.