Constituents from Gymnema sylvestre leaves. Part VII. 3β,23 : 16β,28-Di-O-isopropylidene derivative of gymnemagenin
Abstract
Contrary to the earlier literature reports that β-amyrin derivatives containing either 16β,28-diol or 16β,22α,28-triol systems do not form isopropylidene derivatives, gymnemagenin has been observed to form such a derivative involving the 16β,28-diol grouping. Characterization and formation of this derivative are discussed.