Conformational flexibility of disaccharides investigated by multiple field carbon-13 nuclear spin relaxation

✍ Scribed by Peter Söderman; Göran Widmalm

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 77 KB
• Volume: 37
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/(sici)1097-458x(199908)37:8<586::aid-mrc504>3.0.co;2-j

✦ Synopsis

Multiple-field carbon-13 NMR relaxation studies were performed on four disaccharides with different sugar residues, anomeric configurations and substitution positions. Measurements were made in dimethyl sulfoxide at 300 K, leading to conditions outside the extreme narrowing regime. Global correlation times differed between the disaccharides and scaled well with the number of hydroxyl groups of the disaccharides that can hydrogen bond to solvent. The Lipari-Szabo generalized order parameter was similar for the disaccharides with an average of S 2 D 0.75 š 0.03 when a carbon-proton distance of 109.8 pm was used. However, the flexibility at the disaccharide level is expected to be more restricted (higher value of S 2 ) since a longer carbon-proton distance is judged to be more appropriate.