Four new sesquiterpenoids from the soft coral Nephthea chabrollii

Chemical examination of the soft coral Nephthea chabrolii collected from th e Mandapam coast in the Gulf of Mannar, afforded nine sesquiterpenoids of w hich four (1-4) are new. The structures of the new compounds (1-4) have bee n established by the interpretation of spectral data (UV, IR, H-1 NMR, C-13 NMR, H-1-H-1 COSY, NOESY and mass) and chemical methods.