A new cytotoxic polyhydroxysterol from soft coral Sarcophyton trocheliophorum

A new cytotoxic polyhydroxysterol, 23, 24, -dimethylcholest-16(17)-E-en-3β, 5α, 6β, 20(S)-tetraol (2), together with nine known compounds was isolated from the soft coral Sarcophyton trocheliophorum. Their structures were determined by spectroscopic methods. Compound 2 showed potent growth inhibitory activity against human HL60 leukemia, M14 skin melanoma, and MCF7 breast carcinoma cells with EC50 values of 2.8, 4.3, and 4.9 μg/ml, respectively, and exhibited minimal toxicity to normal human peripheral blood lymphocytes.