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Conformational energies of α‐ and β‐D‐glucopyranoses were computed by varying all the ring bond angles and torsional angles using semiempirical potential functions. Solvent accessibility calculations were also performed to obtain a measure of solvent interaction.

The results indicate that the ⁴C₁ (D) chair is the most favored conformation, both by potential energy and solvent accessibility criteria. The ⁴C₁ (D) chair conformation is also found to be somewhat flexible, being able to accommodate variations up to 10° in the ring torsional angles without appreciable change in energy. Observed solid‐state conformations of these sugars and their derivatives lie in the minimum‐energy region, suggesting that the substituents and crystal field forces play a minor role in influencing the pyranose ring conformation. Theory also predicts the variations in the ring torsional angles, i.e., CCCC < CCCO < CCOC, in agreement …