Three new flavonoid glycosides from the herbaceous stems of <i>Ephedra intermedia</i>

Phytochemical investigation of the <i>n</i>-butanol extracts of the herbaceous stems of <i>Epheda intermedia</i> led to the isolation of eight flavonoids that included three new flavonoid glycosides (<b>1</b>-<b>3</b>) and five previously reported analogues (<b>4</b>-<b>8</b>). Their structures have been identified on the basis of various spectral data. Besides, all the flavonoids were tested <i>in vitro</i> for their ability to inhibit <i>α</i>-glucosidase under the positive control of acarbose, and the results indicated that none of them exhibited significant inhibitory effect on <i>α</i>-glucosidase at 100 μM.