ABSTRACT The chemical investigation on the diethyl ether extract of soft coral Sinularia sp. collected from the South China Sea has led to the isolation and characterization of two new steroids ( 1 and 2 ) and two new α ‐tocopherylquinones ( 3 and 4 ), along with four known related analogs ( 5 – 8 ). The structure of new compounds 1 – 4 was determined by the combination of extensive spectroscopic data analyses, chemical conversion, and comparison of the spectral data with those of corresponding reported compounds in the literature. In bioassays, compound 6 displayed moderate cytotoxic effects against MV‐4‐11, MDA‐MB‐231, and HT‐29 cells with IC 50 values of 19.47 ± 0.33, 15.5 ± 0.46, and 12.26 ± 0.19 µM, respectively. In addition, compound 1 exhibits cytotoxic effects against Hep3B cells with IC 50 values of 26.45 ± 0.92 µM and compound 3 shows cytotoxicity against MV‐4‐11 cells with IC 50 values of 37.63 ± 0.53 µM.
Jin et al. (Sat,) studied this question.