Conformation and solvation. Hydrophobic hydration and preferential solvation of some monosaccharides in mixtures of water and N,N-dimethylformamide

Abstract

Enthalpies of solution of α-D-glucose, β-D-glucose, α-D-galactose and D-mannose in binary solvent mixtures of water and N,N-dimethylformamide at 298.15 K over the whole mole fraction region are reported. The exothermic deviations of linear behaviour are considered to result from preferential hydrogen bonding of the functional groups and hydrophobic hydration of the apolar surfaces of the solute molecule. The effects are accordingly described by a model which accounts for both kinds of solvation.

Distinctions in the solvation enthalpy of the four hexoses are related to differences in their conformation.