Bioactive Cembranoids, Sarcocrassocolides P-R, from the Dongsha Atoll Soft Coral Sarcophyton crassocaule

New cembranoids, sarcocrassocolides P-R (1-3) and four known compounds (4-7) were isolated from the soft coral Sarcophyton crassocaule. The structures of the metabolites were determined by extensive spectroscopic analysis. Compounds 3-5 and 7 were shown to exhibit cytotoxicity toward a limited panel of cancer cell lines and all compounds 1-7 displayed potent in vitro anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells by inhibiting the expression of inducible nitric oxide synthase (iNOS) protein. Compound 7 also showed significant activity in reducing the accumulation of cyclooxygenase-2 (COX-2) protein in the same macrophage cells.