New terpenoid components from the volatile oils of the soft corals Clavularia viridis and Sarcophyton acutangulum.

A new tetracyclic terpenoid hydrocarbon, cyclosinularane (1), and (+)-alloaromadendrene (2), the enantiomer of terrestrial (-)-alloaromadendrene, have been isolated from the volatile oil of the soft corals Clavularia viridis and Sarcophyton acutangulum, respectively. Their structures have been determined on the basis of NMR spectral analysis and their chiroptical properties.