| Autor: |
Gerbst AG; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Vinnitsky DZ; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Tokatly AI; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Dmitrenok AS; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Krylov VB; Laboratory of Synthetic Glycovaccines, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Ustuzhanina NE; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia., Nifantiev NE; Laboratory of Glycoconjugate Chemistry, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, Moscow 119991, Russia. |
| Abstrakt: |
D-Glucuronic acid is a fundamental building block of many biologically important polysaccharides, either in its non-substituted form or bearing a variety of substituents, among them sulfates. We have previously performed a study of the effects of exhaustive sulfation on the conformational behavior of β-gluronopyranosides. Herein, we report an investigation comparing α- and β-derivatives of this monosaccharide within the title disaccharides using NMR and quantum chemistry approaches. It was found that for α-linked disaccharides, the introduction of sulfates did not greatly affect their conformational behavior. However, for β-derivatives, considerable conformational changes were observed. In general, they resemble those that took place for the monosaccharides, except that NOESY experiments and calculations of intra-ring spin-spin coupling constants suggest the presence of a 1 S 5 conformer along with 3 S 1 in the fully sulfated disaccharide. During the synthesis of model compounds, hydrogen bond-mediated aglycone delivery was used as an α-directing stereocontrol approach in the glucuronidation reaction. |
