The chemistry of the Euphorbiaceae. XX. Further compounds from <i>Beyeria leschenaultii</i> 12β,17-Dihydroxy-16α-(–)-kauran-19-oic acid

Abstract

The title substance was separated from the plant as its methyl ester (IV) and its structure established, partly by conversion into 16a-(-)-kaurane-17,19-dioic acid (VIII) and by other chemical and N.M.R. evidence which locates the secondary hydroxyl. Four known kauranes and a flavone were also isolated from the plant. The conformation of ring c in the 12-oxygenated compounds is discussed.