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.
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