New 18-oxygenated polyhydroxy steroid from a South China Sea soft coral Sarcophyton sp.

One new 18-oxygenated polyhydroxy steroid, (24S)-ergostan-3β,5α,6β,18,25-pentaol 18,25-diacetate (1), along with five known analogues (2–6), was isolated from a soft coral Sarcophyton sp. collected from the South China Sea. The structure of the new compound (1) was elucidated by 1D NMR, 2D NMR and mass spectrometry. The absolute configuration of 1 was determined by the application of the modified Mosher's method. The isolated compounds were assayed for their cytotoxic and antimicrobial activities. [ABSTRACT FROM AUTHOR]