A new sesquiterpene from the South China Sea gorgonian coral Subergorgia suberosa

A new sesquiterpene, namely suberosoid (1), was isolated from the South China Sea gorgonian coral Subergorgia suberosa. The chemical structure of 1 was established as an unusual sesquiterpene containing 4-methylenecyclohex-2-enone system, by extensive analyses of NMR spectroscopy and high-resolution mass spectrometry. Suberosoid (1) exhibited cytotoxic effect against HeLa cell lines with IC₅₀ value being 10.6 μM.