Organic Magnetic Resonance · 1976 · 49 citations · 16 references
Natural SciencesBiochemistryChemistryCarbohydrate ChemistryGlycobiologySpectroscopyCarbohydrate ConformationCarbohydrate SpectroscopyCarbohydrate StructureConformational AnalysisConformational ChangeGlycan StructureCarbohydrate Conformational AnalysisCarbohydrate NmrConfiguration Determination By Nuclear Magnetic Resonance SpectroscopyConformational Analysis Of GlycansCouplingsMagnetic CouplingsNuclear Magnetic Resonance Conformational AnalysisRotamer Analysis
Abstract The complete analysis of the 1 H NMR spectra of the six acetylated glycals as well as that of tetra‐ O ‐acetyl‐2‐hydroxy‐ D ‐glucal has been carried out. The conformation of these compounds, as determined from the proton couplings (±0.05Hz) obtained, has been interpreted in terms of a rapid interconversion equilibrium between the two possible dihydropyran half‐chair conformations. A computer treatment of all observed couplings has been carried out to obtain optimized values for the populations and couplings characteristic of the two alternative half‐chair conformations. The rotamer populations of the acetoxy–methyl group are discussed on the basis of the measured 5 J 16 and 5 J 36 couplings.
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