The separation of substituted Olean-12-en-28-oic acids from the corresponding Urs-12-en-28-oic acid isomers

Naturally occurring pairs of hydroxy-substituted olean-12-en-28-oic and urs-12-en-28-oic acids may be separated by treatment of the mixture with bromine in acetic acid. Members of the ursene family are inert under the conditions used. It is shown that a similar separation is possible with the 12-en-28-ol system. The leaf of Duboisia myoporoides was examined for possible variation of ursolic acid content with location.