Polyphenolic compounds from Geranium pratense and their free radical scavenging activities

Two new polyphenolic compounds, myricetin 3-O-(2"-O-galloyl)-beta -D-glucop yranoside and (-)-6-chloroepicatechin, were isolated from the aerial parts of Geranium pratense subsp. finitimum (Woronow) Knuth, along with three kno wn polyphenolic compounds [quercetin 3-O-(2"-O-galloyl)-beta -D-glucopyrano side, quercetin 3-O-(2"-O-galloyl)-beta -D-galactopyranoside, methyl gallat e] and tryptophan. Quercetin 3-O-beta -D-glucopyranoside, quercetin 3-O-bet a -D-galactopyranoside, quercetin 3-O-(2"-O-galloyl)-beta -D-glucopyranosid e and quercetin 3-O-(2"-O-galloyl)-beta -D-galactopyranoside were found to be effective against free radical induced impairment of endothelium-depende nt relaxation in isolated rat aorta. (C) 2001 Elsevier Science Ltd. All rig hts reserved.