Isolation and structure elucidation of a new flavonol glycoside from Sabia Parviflora.

A new flavonol glycoside named Sabiapside A (1), along with four known compounds, quercetin-3-O-gentiobioside (2), camellianoside (3), isobariclisin-3-O- rutinoside (4), tsubakioside A (5), was isolated from Sabia parviflora. Their structures were elucidated by extensive spectroscopic analysis including MS, UV, IR and NMR data. The antioxidant activities of these glycosides evaluated by ABTS+ and DPPH radical scavenging reaction was higher than that of vitamin C used as the reference antioxidant.