Three new compounds from Anoectochilus roxburghii (Wall.) Lindl

In this study, three new compounds, roxburic acid A (1) and two flavone glycosides isorhamnetin-3-O-alpha-L-rhamnosyl-(1 -> 6)-beta-D-glucopyranose-(1 -> 3)-beta-D-glucopyranoside (2), and kaempferol-7-O-beta-D-glucopyranosyl-(1 -> 3)-beta-D-glucopyranoside (3) were isolated from an ethanol extract of the fresh Anoectochilus roxburghii (Wall.) Lindl., together with 10 known compounds (4-13). The structures of these compounds were comprehensively characterized by HR-ESI-MS, H-1 NMR, C-13 NMR, and 2 D-NMR. The DPPH free radical scavenging activity of the isolated compounds was evaluated, and the results showed that kaempferol-7-O-beta-D-glucopyranosyl- (1 -> 3) -beta-D-glucopyranoside (3) and rutin (11) has the potential antioxidant activity with IC50 values of 139 mu g/mL and 22.5 mu g/mL respectively.

Automated summary

In this study, three new compounds and 10 known compounds were isolated from the ethanol extract of Anoectochilus roxburghii. The structures of these compounds were characterized using various techniques. The isolated compounds exhibited potential antioxidant activity.