On the Flavonoid Constituents from the Roots of Scutellaria baicalensis GEORGI. I

From the roots of Scutellaria baicalensis GEORGI., a new flavonoid, 5, 7, 2', 6'-tetrahydroxyflavone, was isolated, together with 5, 8-dihydroxy-6, 7-dimethoxyflavone and 5, 7, 4'-trihydroxy-8-methoxyflavone. Besides, 7-O-glucuronide methyl esters of wogonin, oroxylin A and baicalein were obtained, which were, however, proved to be the artifacts derived from the corresponding compounds without having methyl ester during the extraction with MeOH.