Two new flavonol glycosides from the leaves of Elaeagnus pungens

The leaves of Elaeagnus pungens were extracted with 70% ethanol and successively purified by column chromatography. Seven constituents were obtained and characterized, all of which belong to the class of flavonol glycosides. Their structures were elucidated on the basis of spectroscopic methods including 1D/2D NMR and MS analysis techniques. The seven flavonol glycosides were determined as kaempferol 3-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 6)-[α-l-rhamnopyranosyl(1 → 2)]-β-d-galactopyranoside (1), isorhamnetin 3-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 6)-β-d-galactopyranoside (2), together with five known compounds, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliu-m bromide assay in vitro showed that the isolated flavonol glycosides showed no proliferation activity in the asthma airway smooth muscle cells, comparing with solvent as the control group.