Terpenoids. Part XV. Structure and Absolute Configuration of Oridonin isolated from Isodon japonicus and Isodon trichocarpus

Abstract
Oridonin, a new diterpenoid from Isodon japonicus and Isodon trichocarpus, has been shown to be ent-7β,20-epoxy-1β,6α,7α,l4α-tetrahydroxy-l6-kauren-15-one (I) on the basis of chemical and spectroscopic evidence.