Rabdosia diterpenoids classification

Tables I—IV list structures of all Rabdosia diterpenoids known at present on the basis of this classification.

The biosynthesis of enmein (62) and oridonin (32), the major bitter principles in the leaves of Rabdosia japonica, has been investigated by E. Fujita and coworkers. It is thought to proceed by a pathway similar to that for cyclic diterpenoids in general, with e r-16-kaurene (116) as an important precursor. A biogenetic pathway and a classification of the Rabdosia diterpenoids based on the biogenesis were proposed 123). 

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