Flavonoid Aglycones and Glycosides from the Leaves of some Japanese Artemisia Species

Abstract

Sixteen Japanese Artemisia taxa were surveyed for flavonoid aglycones and glycosides. The leaves were rinsed with acetone and then extracted with MeOH. Isolated flavonoids were identified by UV, LC-MS, acid hydrolysis, ¹H and ¹³C NMR, and/or HPLC comparisons with authentic samples. Thus, nine flavone aglycones, apigenin (10), luteolin (5), chrysoeriol (11), hispidulin (6), jaseosidin (7), nepetin (15), sudachitin (8), luteolin 7-methyl ether (13) and eupatilin (14), three flavonol aglycones, axillarin (9), quercetin 3-methyl ether (16) and 5,7,4′-trihydroxy-3,6-dimethoxyflavone (12), one flavanone aglycone, pinocembrin (4), three dihydroflavonol aglycones, taxifolin (1), taxifolin 3-acetate (2) and padmatin (3) were found in their Artemisia taxa with the various combination. On the other hand, four flavonol glycosides, quercetin 3-O-rutinoside (17), quercetin 3-O-glucoside (18), patuletin 3-O-glucoside (19) and patuletin 3-O-rhamnosylglucoside (20), were isolated from a few Artemisia taxa.