Sesquiterpenoids isolated from an endophyte fungus Diaporthe sp.

Ten new sesquiterpenoids including six brasilane-type sesquiterpenoids, diaporols J-O (1-6), a 3,6-cycloprecapnellane sesquiterpenoid, diaporol P (7), and three drimane sesquiterpenoids, diaporols Q-S (8-10) were isolated from Diaporthe sp., an endophytic fungus associated with the leaves of Rhizophora stylosa collected in Hainan Province, China. The structures of these compounds were elucidated by extensive analysis of NMR, MS, CD spectra and single crystal X-ray diffraction. Among them, compound 9 exhibited moderate cytotoxicity against the SW480 cell line with an IC50 value of 8.72 +/- 1.32 mu M.