Conformational analysis. Part 19—conformational analysis of 6-deoxy-6-fluoro-D-glucose (6DFG) in solution

✍ Scribed by Raymond J. Abraham; Eric J. Chambers; W. Anthony Thomas

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 505 KB
• Volume: 30
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1260301313

✦ Synopsis

Abstract

The conformation of D‐glucopyranose and 6‐deoxy‐6‐fluoro‐D‐glucose (6DFG) in solution, as determined by ^1^H and ^19^F NMR, is reviewed. The ^1^H NMR spectra of α‐ and β‐methyl D‐glucopyranosides and 6DFG in methanol, acetone, DMSO, and aqueous solution were acquired and fully analysed. A ^19^F NMR spectrum of the methanol 6DFG solution, together with a ^1^H COSY spectrum of α‐6DFG in methanol, were recorded. Accurate analyses of the ABC and ABCX spectra produced by the CHCH~2~OH and CHCH~2~F moieities, respectively, were performed, and from the vicinal J(H‐5,H‐6) coupling constants the populations of the three possible staggered rotamers about the C‐5C‐6 bond were calculated. The rotamer in which F is antiperiplanar to the ring O is particularly disfavoured, whereas the rotamer with F antiperiplanar to H‐5 is most favoured. This general trend was seen for both pyranose anomers in all four solvents.