DITERPENOIDS FROM ISODON ERIOCALYX

A new ent-kaurane diterpenoid named maoecrystal P and a known compound coetsoidin A were isolated from the dried leaves of Isodon eriocalyx. They represent the only two ent-kaurane diterpenoids possessing an al pha,beta-unsaturated ketone functional group in ring B to be isolated from Isodon genus plants so far. The structures were elucidated on the basis of spectroscopic methods. (C) 1997 Elsevier Science Ltd.