Specific rotation as a property to validate monosaccharide conformations

Specific rotation ([α]D) values were calculated for the 15 conformations of xylopyranose that are the most stable in the gas phase and in aqueous solution. The effects of different theoretical descriptions and the medium on the geometry of the conformers and the [α]D values are evaluated. Differences in [α]D values found for the same conformer in all descriptions used were smaller than those found between any two different conformers in the same description. The difference between [α]D values is prominent, even for two conformations that are distinguished from each other only by the orientation of one secondary hydroxyl group. This finding suggests that [α]D values may potentially be used in the validation of monosaccharide conformations that are theoretically sampled.

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► 15 Xylose conformations are described in different levels of theory, in gas-phase, and solution.
► Boltzmann population values for individual conformers are presented, and compared to the experimental anomeric α:β ratio.
► Specific rotation values for individual conformers are presented.
► The final theoretical specific rotation value is compared to the experimental benchmark.
► Specific rotation values are proposed to validate conformational sampling.