Meroditerpenoids from a formosan soft coral Nephthea chabrolii

Eight new meroditerpenoid-related metabolites, including one naphthoquinone derivative, chabrolonaphthoquinone B (1), four tetraprenyltoluquinone-related compounds, chabrolobenzoquinones E-H (2-5), and three tetraprenyltoluquinol-related metabolites, chabrolohydroxybenzoquinones E-G (6-8), were isolated from the organic extract of a Taiwanese soft coral Nephthea chabrolii. The structures of 1-8 were elucidated on the basis of extensive spectroscopic analysis and by comparison of the data with those of the related metabolites. Cytotoxic activity of metabolites 1-3 and 5-8 against a limited panel of cancer cell lines is also described.