Bioactive Terpenes from the Soft Coral Heteroxenia sp. from Mindoro, Philippines

A marine soft coral species of the genus Heteroxenia collected from Mindoro Island, Philippines yielded two cadinene sesquiterpenes, (+)-α-m uurolene (1) and a novel derivative (+)- 6 -hydroxy-α-muurolene (2 ), as well as the biologically active polyhydroxysterol, sarcoaldosterol A (3). The structure of the novel compound was unambiguously established on the basis of NMR spectroscopic ( H, C, COSY, H-detected direct and long range C - H correlations) and mass spectrometric (EIMS) data. All compounds were active against the phytopathogenic fungus Cladosporium cucumerinum. The isolated terpenes were also active in the brine shrimp lethality test.