Phenolic Glycosides with Antioxidant Activity from the Stem Bark of <i>Populus davidiana</i>

Phytochemical study on the EtOAc-soluble fraction of the stem bark of <i>Populus davidiana</i> resulted in the isolation of 10 phenolic glycosides (<b>1</b>−<b>10</b>), which were identified on the basis of physicochemical and spectroscopic analyses. Among these, three new compounds, populosides A−C (<b>1</b>−<b>3</b>), were determined to be 2-coumaroylmethyl-4-hydroxyphenyl-<i>β</i>-d-glucopyranoside, 2-coumaroylmethylphenyl-<i>β</i>-d-glucopyranoside, and 2-feruoylmethylphenyl-<i>β</i>-d-glucopyranoside, respectively. Compounds <b>1</b>−<b>10</b> were tested for their radical scavenging activity against an azo radical, ABTS<sup>•+</sup>. Of these, populosides A−C (<b>1</b>−<b>3</b>), populoside (<b>4</b>), grandidentatin (<b>8</b>), salireposide (<b>9</b>), and coumaroyl-<i>β</i>-d-glucoside (<b>10</b>) exhibited antioxidant activity in this assay.