A New Aurone Glucoside and a New Chalcone Glucoside from Bidens bipinnata Linne

A new aurone glucosid e, bidenoside A, ( Z)-6-O-(3, 6-di-O-acetyl-β-D-glucopyranosyl)-6, 7, 3' , 4'-tetrahydroxyaurone (1) and a new chalcon e glucoside, bidenoside B, 2' , 4', 6' -trimethoxy-4-O-β -D-glucopyranosyldihydrochalcone (4), together with five known cons tituents have been isolated from the aerial parts of Bidens bipinnata.These structures have been elucidated on the basis of spectroscopic methods.Bidens bipinnata, a weed of the A sterceae family, is widely di stributed in China.It has been used as a folk medicine for various diseases ，such as infla mmations, rheumatism, sore throat, hypertension and diabetes. 1In this paper we report the isolation and structural elucidation of a new aurone glucoside, ( Z)-6-O-(3, 6-di-O-acetyl-β -D-glucopyranosyl)-6, 7, 3' , 4'-tetrahydroxyaurone (1), two known auron glucosides, (Z)-6-O-β-D-glucopyranosyl-6, 7, 3', 4'-tetrahydroxyaurone (2) 2 and (Z)-6-O-(6-O-acetyl-β-Dglucopyranosyl)-6, 7, 3', 4'-tetrahydroxyaurone (3), 2 a new chalcone glucoside, 2', 4', 6'-trimethoxy-4-Oβ-D-glucopyranosyldihydrochalcone (4), together with th ree known flavonoid glycos ides, quercetin 3-O-β-D-glucopyranoside (5), 3 quercetin 3-O-α-L-rhamnoside (6) 4 and iso-okanin 7-O-β-D-glucopyranoside (7) 5 from this plant.The EtOAc soluble part obtained fr om EtOH extract was separated on silica gel and octadecyl silica gel (ODS) column chromatography, successively, followed by HPLC to isolate compounds (1, 4).The n-butanol fraction was separated on silica gel and octadecyl silica gel (ODS) column chromatography, successively, followed by HPLC to isolate compounds (2, 3, 5, 6, 7).