Sesquiterpene constituents from the soft coral Sinularia nanolobata

Using various chromatographic separations, four sesquiterpenes (1–4), including two new compounds, nanolobatols A and B (1 and 2), were isolated from the Vietnamese soft coral Sinularia nanolobata. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H–1H COSY, NOESY and FT-ICR-MS) and by comparison with the literature values. The cytotoxic activity of isolated compounds against a panel of eight human cancer cell lines was also evaluated.