Two new phenolic glycosides with anti-complementary activity from the roots of Sanguisorba officinalis L

Sanguisorba officinalis L. is a traditional herbal plant that belongs to the genus Sanguisorba and the family Rosaceae. Two new phenolic glycosides (1–2), ten known phenolics (3–12), and six known monoterpenoid glycosides (13–18) were isolated from the roots of S. officinalis using silica gel column and preparative middle pressure liquid chromatography (MPLC). The chemical structures were elucidated based on extensive spectroscopic experiments, including 1D and 2D NMR as well as HR-ESI-MS, and comparison with those reported in the literature. Compounds 3–5, and 13 were isolated from the Rosaceae family and compound 7 was obtained from the genus Sanguisorba for the first time. Additionally, all compounds were evaluated for their anti-complementary activities against the classical pathway. Furthermore, compounds 1, 5, 9, and 14 showed significant anti-complementary activities with the 50% haemolytic inhibition concentrations (CH50) values of 0.40 ± 0.03, 0.57 ± 0.01, 0.51 ± 0.07, and 0.53 ± 0.05 mM, respectively.