Bioactive Cembranoids from the Dongsha Atoll Soft Coral Lobophytum crassum

Two new metabolites, crassumolides H and I (2 and 3), and crassumolide G (1) which was discovered for the first time from natural sources, were isolated from the ethyl acetate extract of a Taiwanese soft coral Lobophytum crassum, along with three known metabolites 4-6. The structures of metabolites 1-3 were elucidated by extensive spectroscopic analysis and comparison of the NMR data with those of known compounds. Compounds 1-3 were found to inhibit the accumulation of the pro-inflammatory iNOS and COX-2 proteins at 10 mu M in LPS-stimulated RAW264.7 marcophage cells.