Constituents of dipterocarpaceae resins. Part II. Structure of dryobalanone from Dryobalanops aromatica

Abstract

Dryobalanone from Dryobalanops aromatica resin was shown to be 20(S)-20,21-dihydroxydammar-24-en-3-one (I; R = OH). Dryobalanone underwent 1,2-diol cleavage with periodate; and hydrogenolysis of drybalanone 21-toluene-p-sulphonate with lithium aluminium hydride yielded dammarenediol-II. Other non-acidic triterpenes isolated from the resin include erythrodiol and the dammarane compounds dipterocarpol, dammarenediol-II, and ocotillol-II.