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Updated: Jul 17, 2026

Exploring Protein-Glycan Interactions: Advances in Nuclear Magnetic Resonance
Published on: August 26, 2025
Relationship between structure and three-bond proton-proton coupling constants in glycosaminoglycans
1Institute of Chemistry, Slovak Academy of Sciences, 845 38 Bratislava, Slovakia. hricovini@savba.sk
Abstract:
Theoretical calculations using the DFT theory at the B3LYP/6-311++G(**) level were used to determine the molecular geometry of various glycosaminoglycan (GAG) molecules. Three-bond proton-proton spin-spin coupling constants ((3)J(H-C-C-H)) were then computed and compared with the published experimental data of selected mono- and disaccharides. The computed (3)J(H-C-C-H) values showed a strong dependence on the molecular geometry and varied up to 12 Hz. This dependence was expressed in a simple analytical form relating (3)J(H-C-C-H) and torsion angles. The population of conformers in heparin and other biologically active GAGs has also been estimated using the computed coupling constants.
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