New Terpenoids from the Soft Coral Sarcophyton trocheliophorum and Their Anti-inflammatory Activities.

A detailed chemical investigation of the Hainan soft coral Sarcophyton trocheliophorum led to the isolation of three new cembrane-type diterpenoids (sartrocheliols F-H), one new aromadendrane-type sesquiterpenoid (sartrocheliol I), a new natural cembranoid, and five known structurally related analogues. Their structures were elucidated by extensive spectroscopic analysis, quantum mechanical nuclear magnetic resonance methods, time-dependent density functional theory-electronic circular dichroism calculations, as well as comparison with literature data. A plausible biogenetic pathway connecting the isolated compounds was proposed. In bioassay, spathulenol (9) exhibited moderate inhibitory activity on nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages.