CARBOHYDRATES IN SOLUTION

Table 6. Sweetness and Flavor of Selected Carbohydrates in Solution...

We thank Dr Mahesh Sundararajan for helpful discussion regarding the modelling of iron containing proteins and Dr Richard Bryce for discussion regarding the modelling of carbohydrates in solution. We also thank Dr James J. P. Stewart for helpful discussion regarding the gradient-based optimisation of semi-empirical parameters. 

E. A. Kabat, in Carbohydrates in Solution, Advances in Chemistry Series No. 117, pp. 334-361. American Chemical Society, Washington, D.C., 1972. 

Complexes of metal cations with carbohydrates in solution, 47, 1 -43 Courtois, Jean Emile, obituary of, 49,11 -18 Cyclomalto-oligosaccharides(cyclodextrins), inclusion complexes of, 46, 205-249 addendum to, 46, 333-335... 

Macrostructure of mucus glycoproteins in solution, 47, 345-381 Metal cations, complexes of, with carbohydrates in solution, 47, 1 -43 Molecular structure of lipid A, 50,211 -276 Monosaccharides, decomposition of, 47, 203-278... 

A coirplete understanding of the role of carbohydrates in biological systems requires knowledge of the distribution at equilibrium of the various conformers in aqueous solution. The conformational behavior of carbohydrates in solution can be examined from different vantage points (1,), but the most relevant approach is, no doubt, study of dilute solutions themselves. At present, high resolution NMR spectroscopy is the primary tool for determination of three-dimensional structure of oligosaccharides in solution. Optical rotation is also very sensitive to conformation (2) and there is a new, semi-enqpirical theory of optical rotation of oligosaccharides ( ). 

In alcoholic solution, carbohydrates possibly complex with undissociated molecules (ion pairs) of salt, as well as with free cations. Data from optical rotation experiments1 suggest that, even in aqueous solution, undissociated molecules of salt may be associated with the carbohydrate (see Section II, 7, p. 230). On the other hand,/ree anions do not appear to complex with carbohydrates in solution (see Section II, 8, p. 234). 

Electrophoretic migration of carbohydrates in solutions of alkali metal salts or alkaline-earth metal salts demonstrates the ability of carbohydrates... 

Structural study of polysaccharides and other carbohydrates in solution or in the amorphous state has been significantly enhanced through the application of Fourier-transform, infrared spectroscopy. Among the advantages of this method may be mentioned the high quality of the spectra, and the in-house ability to interact with the computer, so that the digitized spectra may be stored and manipulated in such a way that additional information is obtained. The application of F.t.-i.r. spectroscopy in the field of carbohydrate chemistry and biochemistry is still in its infancy,182 but... 

These papers show the broad scope of the symposium and the intense interest of chemists in the changes which take place in compounds prior to and during chemical reactions of carbohydrates in solution. 

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