Dysideasterols A-E, five new uncommon polyhydroxylated steroids from the south China sea sponge Dysidea sp.

Five new uncommon polyhydroxylated steroids, dysideasterols A-E (1-5), were isolated from the South China Sea sponge Dysidea sp. Their structures were established by detailed analysis of spectral data and verified via single-crystal X-ray-diffraction analysis of compound 1. The absolute configuration of 1 was determined by the modified Mosher method.