Six new polyoxygenated cembrane-based diterpenoids possessing a trans-fused alpha-methylene-gamma-lactone, crassocolides A-F (1-6), have been isolated along with the known compound 7 from the ethyl acetate extract of a Taiwanese soft coral, Sarcophyton crassocaule. The structures of 1-6 have been established by detailed spectroscopic analysis, including 2D NMR (1H-1H COSY, HMQC, HMBC, and NOESY) spectroscopy, while their absolute configurations were determined using a modified Mosher's method for 1. The structure of 5 was further proven by X-ray diffraction analysis. The full assignment of NMR data of 7 is reported herein for the first time. The cytotoxicity of crassocolides 1-4, 6, and 7 against a limited panel of cancer cells was also determined.

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Six new sesquiterpenoids, paralemnolins J-O (1-6), along with one novel norsesquiterpenoid, paralemnolin P (7), have been isolated from the soft coral Paralemnalia thyrsoides. The structures of metabolites 1-7 were established on the basis of extensive NMR study and chemical methods. The structure of 5 was further confirmed by a single-crystal X-ray analysis. Cytotoxicity of these metabolites toward a limited panel of cancer cell lines also is described.

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