Isolation of Flavonol Glycosides fromGinkgo bilobaLeaves

Abstract

6-Hydroxykynurenic acid and nine flavonol glycosides were isolated and identified from the leaves of GINKGO BILOBA: three of them were identified in Ginkgo for the first time, and two others are unusual P-coumaroyl esters.

Toward better annotation in plant metabolomics: isolation and structure elucidation of 36 specialized metabolites from Oryza sativa (rice) by using MS/MS and NMR analyses

“…MS/MS spectra of compound 19 showed major fragment ions at m / z 509 [(M + H)-146] + and 347 [(M + H)-146-162] + , indicating the loss of deoxyhexose and hexose groups. Furthermore, comparing the 1 H-NMR spectral data with those in the literature, they were assigned as syringetin 3- O -β- d -glucopyranoside ( 18 ) (Guo et al 2010) and syringetin 3- O -rutinoside ( 19 ) (Victoire et al 1988). …”

3-Hydroxymethylglutaryl Flavonol Glycosides from a Mongolian and Tibetan Medicine, Oxytropis racemosa

“…In addition, 13 known compounds were elucidated as uracil, 7) isorhamnetin 3-O-a-arabinopyranoside, 8) rhamnetin 3-O-b-glucopyranoside (4), 9) rhamnocitrin 3-O-b-glucopyranoside (5), 10) adenosine, 11) quercetin 3-O-a-arabinopyranoside, 8,12) isorhamnetin 3-O-b-glucopyranoside (6), 13) genistein 4Ј-O-b-glucopyranoside (7), 14) dihydrokaempferol 4Ј-Ob-glucopyranoside (8), 15) acacetin 7-O-b-rutinoside (9), 16) isorhamnetin 3-O-b-rutinoside (10), 17,18) quercetin 3-O-bglucopyranoside (11), 19) and rutin (12), 19) by spectroscopic analysis.…”

Cloning and characterization of a glucosyltransferase that reacts on 7-hydroxyl group of flavonol and 3-hydroxyl group of coumarin from tobacco cells

“…To confirm the site of glucosylation by rNTGT2, the glucosylated product of kaempferol was purified by preparative HPLC. The glucosylated product of kaempferol was identified as kaempferol 7-O-β-glucopyranoside by the comparisons of its FAB-MS, 1 H-NMR and 13 C-NMR spectra with those described in the literature [25]. The site of glucosylation, 7-OH, was finally confirmed by the 1 H-Detected Heteronuclear Multiple Bond Connectivity experiment, in which, the correlation of the anomeric proton (δ H 5.05) with C-7 (δ 164.3) was observed.…”