Clionaterpene, a New Cadinene Sesquiterpene from the Marine Sponge Cliona sp.

Clionaterpene (1), a new cadinene sesquiterpene, along with six known compounds 2-7 were isolated from the marine sponge Cliona sp. The structure of 1 with absolute configuration was determined by the spectroscopic data (UV, IR, MS, and NMR) and quantum chemical calculation. Compound 1 was the first cadinene sesquiterpene metabolite isolated from this genus. In addition, the cytotoxic and antibacterial activities of these compounds were evaluated. However, none of them exhibited significant inhibition effects.