Three new flavonoid glycosides from Oxytropis myriophylla.

Three new flavonoids, myriophylloside I, II and III, were isolated from Oxytropis myriophylla (Leguminosae), together with four known flavonoid glycosides: isorhamnetin-3-O-β-D-glucoside, isorhamnetin-3-O-α-L-arabinosyl(1→6)-β-D-glucoside, quercetin and rutin. The structural elucidations of all the compounds were based on extensive spectroscopic methods, including HRESIMS and 2D-NMR experiments (HSQC, HMBC, (1)H-(1)H COSY and HSQC-TOCSY), UV, IR and chemical evidence, together with comparison with reference values.