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Updated: Aug 15, 2026

Semi-Targeted Ultra-High-Performance Chromatography Coupled to Mass Spectrometry Analysis of Phenolic Metabolites in Plasma of Elderly Adults
Published on: April 22, 2022
Polyphenolic constituents of Callistemon lanceolatus leaves
I I Mahmoud1, F A Moharram, M S A Marzouk
1Pharmacognosy Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt.
Abstract:
Two new flavonol glycosides, kaempferol 3-O-beta-D-galacturonopyranoside and quercetin 3-O-(2"-O-galloyl)-beta-D-glucoronopyranoside, were isolated, from leaves of Callistemon lanceolatus DC, as well as eighteen known polyphenols (phenolic acids, flavonoids and three tannins). All structures were established mainly on the basis of chemical and spectroscopic analysis (UV, 1D NMR and negative ESI-MS) and finally confirmed by 2D NMR experiments (HMQC and HMBC), in the case of flavonoid glycosides and tannins.
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