[Study on the Flavonoids and Biological Activity of Rubus sachalinensis].

Objective: To study the chemical constituents and biological activity of Rubus sachalinensis.

Methods: The compounds in the ethyl acetate and n-butanol fraction were isolated and purified by macroporous resin,Sephadex LH-20 column chromatography,and reverse-phase preparative HPLC. The structures were identified by various spectroscopic data such as 1D,2D-NMR,HRMS. Antioxidant,anti-inflammatory and cytotoxicity of the compounds were determined by FRAP,Griess and MTT methods.

Results: Eight compounds were isolated from the ethyl acetate and n-butanol extract of Rubus sachalinensis,and identified as kaempferol-3-O-β-D-butyl glucuronate( 1),quercetin-3-O-β-D-butyl glucuronate( 2),quercetin-3-O-β-D-glucopyranoside( 3),cis-tiliroside( 4),tiliroside( 5),quercetin-3-O-β-D-ethyl glucuronate( 6),quercetin( 7) and kaempferol( 8). Activity assay showed that the compounds 1 ~ 8 had different levels of antioxidant activity,all the compounds showed cytotoxicities of IC50 greater than 200 μmol / L.

Conclusion: Flavonoids are the main antioxidant consitituents of Rubus sachalinensis and have a good anti-inflammatory activity. All the compounds are isolated from this plant for the first time,compounds 1,2,6 are obtained from the this genus for the first time.