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Updated: Sep 30, 2026

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical (Methylation) and Physical (Mass Spectrometry, Nuclear Magnetic Resonance) Techniques
Published on: March 24, 2016
Solution behavior of methyl beta-xylobioside: conformational flexibility revealed by n.m.r. measurements and
M Hricovíni1, I Tvaroska, J Hirsch
1Institute of Chemistry, Slovak Academy of Sciences, Bratislava.
Abstract:
The conformations of methyl beta-xylobioside in solution have been determined by n.m.r. spectroscopy. Interglycosidic 3JC,H values and the chemical shifts of the 13C resonances were measured at various temperatures in the range 238-378 K for solutions in 1,4-dioxane, methanol, methyl sulfoxide, and water. The temperature and solvent dependencies of the data obtained suggest conformational flexibility. Quantum-chemical PCILO calculations, with evaluation of the solvent effects, and molecular mechanics calculations revealed the existence of 7 low-energy regions for which the geometries and energies were determined. The computed abundances of conformers and averaged J values accord with the experimental data.
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