From the n-BuOH-soluble fraction of a MeOH extract of the fruits of Rosa soulieana, one new phenolic glucoside (1) was isolated along with five known compounds, comprising two lignin glycosides, two flavonoid glycosides and a phenolic glycoside. The chemical structure of the new compound was elucidated by extensive spectroscopic analyses, including ESI-MS, UV, IR, (1)H and (13)C NMR, DEPT and 2D NMR (HSQC and HMBC). All the isolated compounds were evaluated for their antioxidant activity by using ABTS (2,2'-azino-bis(3-ethylbenzoline-6-sulfonic acid)) assay. Among these compounds, 1, 3 and 6 exhibited strong scavenging activity in ABTS(·+)(SC50 = 102.10, 193.85, 65.38 μmol/L, respectively) compared with the positive control l-ascorbic acid (Vc) (SC50 = 117.16 μmol/L).
Keywords: ABTS; Rosa soulieana; antioxidative; phenolic glucoside.