title: Conformational preferences in diglycosyl disulfides: NMR and molecular modeling studies.
abstract: The conformations of several β1→β1' diglycosyl disulfides were investigated by NMR and computational methods. Experimental data, such as NOEs, proton-proton and proton-carbon-13 coupling constants, measured for solutions in DMSO, are in good agreement with values obtained by MD simulations in explicit DMSO. The disulfide torsion angles (C1-S-S-C1') preferentially sample values close to either +90° or -90° (+g or -g) and appear as the main metric that determines the conformational behavior of these glycomimetics. There is more conformational freedom around the C1-S and C1'-S' bonds (Φ and Ω torsions, respectively) and population cluster analysis allowed to identify up to four allowed conformational regions for each of the +g or -g forms. Population analysis of the hydroxylic group rotamers, based on proton-proton and proton-carbon-13 couplings as well as on calculated hydrogen bonding statistics, did not reveal any significant intramolecular hydrogen bonds in DMSO solution.
authors: Department of Organic Chemistry, University of Debrecen, Pf. 20., H-4010 Debrecen, Hungary.
authors: Krisztina
authors: K
authors: Fehér
authors: Richard P
authors: RP
authors: Matthews
authors: Katalin E
authors: KE
authors: Kövér
authors: Kevin J
authors: KJ
authors: Naidoo
authors: László
authors: L
authors: Szilágyi
mesh_terms: D000117:Acetylglucosamine / Q000737:chemistry; D002236:Carbohydrate Conformation; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry*; D005690:Galactose / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry*; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000737:chemistry; D056004:Molecular Dynamics Simulation; D012997:Solvents; D013816:Thermodynamics
chemical_list: D004220:Disulfides; D006027:Glycosides; D012997:Solvents; D005947:Glucose; D008358:Mannose; D000117:Acetylglucosamine; D005690:Galactose; D004121:Dimethyl Sulfoxide