摘要：

13C NMR spectra for a number of dihydroflavones, dihydroflavonols, flavans, chalcones, flavonols, an isoflavone and several glycosides in DMSO-d 6 solvent are reported and analysed. The use of established substitution additivity rules and 13C- 1H coupling constants together with suitable model compounds has permitted near complete, self-consistent interpretations of these spectra. Sites of C-methylation and glycosylation are readily determined as also is the interglycosidic linkage within the disaccharide of flavonoid O-diglycosides. Stereochemical effects are observed in the spectra of the dihydro-flavonoids and some flavonol 3-O-glycosides.

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