COETSOIDIN A, A NEW DITERPENOID FROM RABDOSIA COETSOIDES C. Y. Wu

From the leaves of Rabdosia coetsoides C. Y. Wu, a new diterpenoid, coetsoidin A (Ⅰ) was isolated and its structure was established by spectroscopic and X-ray diffraction analysis. It is the first instance of a kaurene type diterpenoid possessing α,β-unsaturated ketone functionality in ring B.