ISegetoside I (Fig. 1A: Purity >85%) was isolated in our labora-tory (Centre for Research and Development of New Drugs, JiangsuUniversity) as previously described with some slight modification[18]. Briefly, crude ethanol extract of V. segetalis was prepared andthe n-butanol fraction with bioactivity was run on silica columnchromatography using a CH2Cl2/MeOH mixture. The active subfrac-tion (CH2Cl2/MeOH, 1:1) was further purified on RP-8 and RP-18columns successively with MeOH–H2O gradient elution to givesegetoside I (MeOH–H2O, 7:3). HPLC, TLC, LC–MS/MS (Fig. 1B) andcomparative spectroscopic literature analysis were used to authen-ticate the purity and structure of segetoside I.