Phenolic metabolites from Pyruscalleryana and evaluation of its free radical scavenging activity.
Investigation of the aqueous alcoholic extract of Pyruscalleryana Decne. leaves led to the isolation of two new phenolic acids glycosides, namely protocatechuoylcalleryanin-3-O-β-glucopyranoside (1) and 3'-hydroxybenzyl-4-hydroxybenzoate-4'-O-β-glucopyranoside (2), together with nine known compounds among them lanceoloside A and methylgallate, which have been isolated for the first time from the genus Pyrus. Structures of the isolated compounds were established by spectroscopic analysis, including UV, IR, HRESI-MS, and 1D/2D NMR. The total extract and some isolated compounds were determined against DPPH (2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazinyl radical, for their free radical scavenging activity, the total alcoholic extract showed strong antioxidant activity while the two new compounds showed weak antioxidant activity.
Chemistry of Natural Compounds Department, National Research Centre, Dokki, 12622 Cairo, Egypt. mnassar_rg@yahoo.com
Mahmoud I
MI
Nassar
Tahia K
TK
Mohamed
Sayed A
SA
El-Toumy
Ahmed H
AH
Gaara
Walaa A
WA
El-Kashak
Iñaki
I
Brouard
Salah M
SM
El-Kousy
D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D031989:Pyrus / Q000737:chemistry*
D016166:Free Radical Scavengers; D010636:Phenols; D010936:Plant Extracts