Unprecedented furan-2-carbonyl C-glycosides and phenolic diglycosides from Scleropyrum pentandrum

Abstract

Five unprecedented furan-2-carbonyl C-glycosides, scleropentasides A-E, and two phenolic diglycosides, 4-hydroxy-3-methoxybenzyl 4-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside and 2,6-dimethoxy-p-hydroquinone 1-O-β-D-xylopyranosyl-(1→6)-β-d-glucopyranoside, were isolated from leaves and twigs of Scleropyrum pentandrum together with potalioside B, luteolin 6-C-β-D-glucopyranoside (isoorientin), apigenin 8-C-β-D-glucopyranoside (vitexin), apigenin 6,8-di-C-β-D-glucopyranoside (vicenin-2), apigenin 6-C-α-L-arabinopyranosyl-8-C-β-D-glucopyranoside (isoschaftoside), apigenin 6-C-β-D-glucopyranosyl-8-C-β-D-xylopyranoside, adenosine and l-tryptophan. Structure elucidations of these compounds were based on analyses of chemical and spectroscopic data, including 1D and 2D NMR. In addition, the isolated compounds were evaluated for their radical scavenging activities using both DPPH and ORAC assays.