Flavone C-Glycosides from Viola yedoensis MAKINO

A new flavone C-glycoside, apigenin 6-C-α-L-arabinopyranosyl-8-C-β-L-arabinopyranoside, has been isolated from Viola yedoensis together with the known compounds, apigenin 6,8-di-C-α-L-arabinopyranoside, apigenin 6-C-α-L-arabinopyranosyl-8-C-β-D-glucopyranoside (isoschaftoside), apigenin 6-C-β-D-glucopyranosyl-8-C-α-L-arabinopyranoside (schaftoside), apigenin 6-C-β-D-glucopyranosyl-8-C-β-L-arabinopyranoside (neoschaftoside), apigenin 6,8-di-C-β-D-glucopyranoside (vicenin-2), apigenin 6-C-α-L-arabinopyranosyl-8-C-β-D-xylopyranoside, apigenin 6-C-β-D-xylopyranosyl-8-C-α-L-arabinopyranoside, luteolin 6-C-β-D-glucopyranoside (isoorientin) and luteolin 6-C-α-L-arabinopyranosyl-8-C-β-D-glucopyranoside (isocarlinoside). The structures were determined by spectroscopic methods and new or revised 1H- and 13C-NMR spectral assignments are proposed for some compounds.