A new dihydrodibenzodioxinone from Hypericum x 'Hidcote'
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Updated: Jun 22, 2026

High-resolution Tandem Mass Spectrometry for Studying Chemical Constituents of Gynura bicolor DC
Published on: February 2, 2024
Longru Sun1, M Mukhlesur Rahman, Brian W Skelton
1Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
Abstract:
One new compound, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxin-2(3H)-one (1), was isolated from the aerial parts of the hybrid Hypericum x 'Hidcote', together with 8 known compounds: caryophyllene-4,5-epoxide, quercetin, quercitrin, quercetin-3-O-beta-D-galactopyranoside, epicatechin, betulinic acid methyl ester, beta-sitosterol and beta-sitosterol glucoside. The structure of the new compound, as well as its absolute configuration, was established by means of spectroscopic data analyses, including 2D NMR spectroscopy and X-ray structural analysis.
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