Cadinane-type sesquiterpene from Japanese soft coral of the genus Xenia and its biological activities

The marine soft coral genus Xenia is a rich source of terpenoids. A new cadinane-type sesquiterpenoid, xenitorin G (1), along with two known compounds, palustrol (2) and rel-(1R,2E,4R,7Z)-4-hydroxy-α,α,4,8-tetramethyl-2,7-cyclodecadiene-1-methanol (3), were isolated and characterized from soft corals of the genus Xenia collected on Yoron Island, Kagoshima Prefecture, Japan. The chemical structures of these secondary metabolites were characterized using nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and Fourier-transform infrared spectroscopy. Antifouling assay using mussels and toxicity assay in brine shrimp were also conducted for compounds 1–3.