Natural clovanes from the gorgonian coral rumphella antipathies

Three natural clovane-related sesquiterpenoids, 2β-acetoxyclovan- 9α-ol (1), 9α-acetoxyclovan-2β-ol (2) and clovan-2β, 9β-diol (3), were isolated from the gorgonian coral Rumphella antipathies. The structures of clovanes 1-3 were elucidated by spectroscopic methods and by comparison of the spectral data with those of known clovane analogues. This is the first time that clovanes 1-3 have been isolated from a natural source. Clovanes 1 and 2 displayed inhibitory effects on the generation of superoxide anions and the release of elastase by human neutrophils.