[Studies on flavonoids from Scutellaria moniliorrhiza]

By means of preparative HPTLC and column chromatography over silica gel and Sephadex LH-20, nineteen flavonoids were isolated and purified from the whole plants of Scutellaria moniliorrhiza. Based on the physico-chemical properties and spectral data, their structures were identified as： apigenin (1), luteolin (2), wogonin (3), oroxylin A (4), 6-methoxynaringein (5), 5,7,4'-trihydroxy-6,8-dimethoxyflavone (6), 5,7,8-trimethoxyflavone (7), 3,5,6,7-tetramethoxyflavone (8), 7-hydroxy-4',5,6,8-tetramethoxyflavone (9), 5,7,2'-trihydroxy-6-methoxyflavanone (10), 5,7,4'-trihydroxy-6-methoxyflavone (11), 5,7-dihydroxy-6,8-dimethoxy -flavone (12), 5,2',6'-trihydroxy-7,8-dimethoxyflavone (13), 5,7,2'-trihydroxy-8-methoxyflavone (14), 5,2'-dihydroxy-7,8-dimethoxyflavanone (15), 2'-hydroxy-5,7,8-trimethoxyflavone (16), 5-hydroxy-7,8-dimethoxyflavone (17), 5,2'-dihydroxy-7,8-dimethoxyflavone (18), and 5-hydroxy-6,7,8-trimethoxyflavone (19). For the first time, compounds 1-19 were isolated from S. moniliorrhiza, and compounds 6, 8, 9, 12, 19 were isolated from the Scutellaria genus.