STUDIES ON FLAVONOID CONSTITUENTS ISOLATED FROM THE LEAVES OF GLYCYRRHIZA URALENSIS FISCH

Four flavonoids were isolated from the alcoholic extract of the leaves of Glycyrrhiza uralensis Fisch. (Leguminosae). On the basis of physicochemical properties and spectroscopic analysis their structures were elucidated as 3, 5, 7, 3′, 4′-pentahydroxy-5′-isoprenylflavone(Ⅰ), 3, 6, 7, 3′, 4′-pentahydroxy-2′-isoprenylflavone((Ⅱ) and 5, 7, 3′, 4′-tetrahydroxy-5′-isoprenyl-flavanone(Ⅲ) and quercetin-3, 3′-dimethylether(Ⅳ). Compounds Ⅰ, Ⅱ and Ⅲ are new compounds and named uralenol, neouralenol and uralenin respectively. Compound Ⅳ was found in this genus for the first time. Compound Ⅲ was shown to be the major constituent in the leaves of Glycyrrhiza uralensis Fishch.