Three new compounds (1-2, 4) along with ten known ones (3, 5-13), were isolated from the whole plant of Erigeron breviscapus. Compounds 1 and 2, two novel C10 acetylenic acids and compound 4, a jasmone glucoside were elucidated by the detailed analysis of 1D and 2D NMR, HRESIMS spectra, and experimental and calculated electronic circular dichroism (ECD). Compounds 1-3 represent the first example of acetylenic acids incorporating C10 skeleton from E. breviscapus. In addition, the antioxidant effects of all compounds were evaluated by ferric reducing power, 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate acid) (ABTS) and 2.2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Our results indicated the significant antioxidant activity of caffeoylquinic acids. Additionally, compounds 10-11 and 13 played protective role on alcoholic liver injury cells in a dose-dependent manner.
Keywords: ECD calculation; Erigeron breviscapus; acetylenic acid glycoside; antioxidant activities; caffeoylquinic acids.