X-ray crystal structure and antioxidant activity of salidroside, a phenylethanoid glycoside

The X-ray single-crystal structure of natural salidroside (= 2-(4-hydroxyphenyl)ethyl beta-D-glucopyranoside; 1), isolated from Cistanche deserticola, is reported for the first time, as well as its absolute configuration. The radical-scavenging activity of 1 towards the superoxide radical anion (O-2(.-)) was determined experimentally by chemiluminescence measurements of the pyrogallol-luminol system, and compared to that of the corresponding aglycone, i.e., tyrosol (= 4-(2-hydroxyethyl)phenol; 2).