Structural studies of 2-(3′,4′-dihydroxyphenyl)-7-β-D-glucopyranos-1-O-yl-8-hydroxychroman-4-one in the liquid and solid states by means of 2D NMR spectroscopy and DFT calculations

Abstract

Homo- and heteronuclear correlated spectroscopy in the liquid phase and the PASS-2D NMR technique in the solid state were applied to the identification and structural studies of the flavanone 2-(3′,4′-dihydroxyphenyl)-7-β-D-glucopyranos-1-O-yl-8-hydroxychroman-4-one 1. The principal elements of the ¹³C chemical shift tensor were established and verified by DFT GIAO calculations. Analysis of the ¹³C δ_ii and comparison with the theoretical shielding parameters calculated for different conformers of 1 in a vacuum were carried out to choose the most reliable geometry in the solid state.