The chemical and chemo‐ecological studies on Weizhou nudibranch Glossodoris atromarginata.

A detailed chemical investigation of the nudibranch Glossodoris atromarginata collected from Weizhou Island, South China Sea, yielded a new spongian‐type diterpene 1, together with the four known‐related compounds 2–5. The structure of the new compound 1 was elucidated by the detailed spectroscopic analysis, the comparison of the spectroscopic data with the known diterpene isoagatholactone, and the 13C chemical shift calculation. In addition, evidence for the absolute stereochemistry of the known compound 2 was, for the first time, provided by the application of time‐dependent density functional theory electronic circular dichroism calculation. [ABSTRACT FROM AUTHOR]