Guaiane sesquiterpenes from the gorgonian collected in the South China Sea.

Echinoflorine (1), a new dimethylamino-substituted guaipyridine alkaloid with a novel γ-lactone-cyclohepta[]pyridine fused skeleton, and three new guaiane sesquiterpene lactones, echinofloranolides A-C (2-4), together with eight known guaiane sesquiterpenes were isolated from the gorgonian collected in the South China Sea. Their structures were elucidated by 1D and 2D NMR, HRESIMS, calculated ECD and DP4+ probability analyses.

Cytotoxic 9,11-secosteroids from the South China Sea gorgonian Subergorgia suberosa.

Ten new 9,11-secosteroids, subergorgols A-J (1-10), including two pairs of epimers (3/4, and 6/7), along with three known analogues (11-13) were isolated from the South China Sea gorgonian Subergorgia suberosa. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses and comparison with the literature data. The cytotoxicities in vitro against three selected human tumor cell lines for all the compounds were evaluated.