| Abstract
| - The solution conformation of a furanose ring can be assessed through PSEUROT analysis of three-bond 1H−1H coupling constants (3JHH) of the ring hydrogens. For each coupling constant, PSEUROTrequires two parameters, A and B, which are used to translate the H−C−C−H dihedral anglepredicted from the 3JHH into an endocyclic torsion angle from which the identity of the conformerscan be determined. In this paper, we have used density functional theory methods to generate afamily of envelope conformers for methyl furanosides 1−8. From these structures, A and B werecalculated for each H−C−C−H fragment. In turn, the values of these parameters for thearabinofuranose ring were used in PSEUROT calculations to determine the conformers populatedby monosaccharides 1 and 2 as well as the furanose rings in oligosaccharides 9−15. The results ofthese analyses are consistent with the low-energy conformers identified from previous computationaland X-ray crystallographic studies of 1 and 2.
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