New antioxidant C-glycosyl flavone and flavonol derivatives from the Tunisian Achille acretica L

• Published in: South African journal of botany 2018-05, Vol.116, p.1-5
• Main Authors: Hichri, F., Ben Salah, N., Omri, A., Hossan, A.S.M., Ben Jannet, H.
• Format: Article
• Language: English
• Subjects: Achillea cretica; Antioxidant activity; Asteraceae; Flavonoids; Flavonol
• ISSN: 0254-6299; 1727-9321
• DOI: 10.1016/j.sajb.2018.02.393

Two new natural compounds, 2′,5′,5,6,7-pentamethoxyflavanol 1 and 3-C-β-D-glucopyranoside 7-O-methylapigenin 2, together with two known compounds, 4′,5,7-trimethoxyquercetin 3 and 6-methoxychroman 4 were isolated from the n-BuOH extract of Achillea cretica aerial parts. All the structures were identified by spectral analysis, 1D (1H, 13C) and 2D NMR (1H-1H COSY, NOESY, HSQC, HMBC) and ESI-MS as well as by comparing their spectroscopic data with those reported in the literature. The antioxidant activity of the isolated compounds was evaluated by DPPH and ABTS assays and the strucuture-activity relationship was discussed. All isolated compounds 1, 2, 3 and 4 showed a significant antioxidant activity. The compound 2 exhibited the highest antioxidant activity with IC50 values of 45.00±2.00μg/ml and 42.00±1.00μg/ml against the DPPH and the ABTS scavenging activity assay, respectively. •Two novel C-glycosyl flavone and Flavonol derivatives were isolated from Achillea cretica.•Structures were characterized by spectroscopic methods.•Isolated compounds were screened for their antioxidant activity.•The antioxidant activity of C-glycosyl flavone was 45.00±2.00μg/ml against the DPPH scavenging activity assay.•The antioxidant activity of C-glycosyl flavone was 42.00±2.00μg/ml against the ABTS scavenging activity assay.