Isolation and identification of antioxidants from Sophora japonica

Abstract

A new flavonol triglycoside, kaempferol 3- O - f - l -rhamnopyranosyl-(1 M 6)- g - d -glucopyranosyl-(1 M 2)- g - d -glucopyranoside ( 1 ), as well as two known kaempferol 3- O -[ f - l -rhamnopyranosyl-(1 M 6)]-[ g - d -glucopyranosyl-(1 M 2)]- g - d -glucopyranoside ( 2 ) and kaempferol 3- O - g - d -glucopyranosyl-(1 M 2)- g - d -glucopyranoside-7- O - f - l -rhamnopyranoside ( 3 ), were isolated from the n -BuOH extract of the pericarps of Sophora japonica by bioassay-guided fractionation. The structure of compound 1 was established by UV, IR, MS, and one- and two-dimensional NMR spectroscopy, including DEPT, NOESY, DQF-COSY, TOCSY, HMQC, and HMBC experiments. Compounds 1 - 3 showed antioxidative activity in DPPH and cytochrome-c assay using HL-60 cell system.