Two new polyhydroxylated steroids from the Hainan soft coral Sinularia sp.

Two new polyhydroxylated steroids, (2 beta,3 beta,4 alpha,5 beta,8 beta,11 beta)-4-methylergost-24(28)-ene-2,3,8,11-tetrol-(1) and (3 beta,5 alpha,6 beta)-ergosta-22,24(28)-diene-3,5,6,19-tetrol (3), together with the six known related steroids 2 and 4-8, were isolated from the Hainan soft coral Sinularia sp. Their structures were elucidated on the basis of spectroscopic analysis and by comparison with previously reported data. The structure of the known compound 9 (hyrtiosterol) was revised as 2 by extensive analysis of the ROESY data and by the NOE difference experiment.