Properties of Monosaccharides

The same research group went further into detail concerning the antimicrobial properties of monosaccharide-coated SWNTs, advantageously exploiting their application for efficient and specific recognition of a nonvirulent strain of Bacillus... 

The chemical properties of monosaccharides are further complicated by the fact that they can exhibit tautomerism in aqueous basic solutions (Figure 1.15). This means that after a short time a basic aqueous solution of a monosaccharide will also contain a mixture of monosaccharides that will exhibit their characteristic chemical properties. For example, a solution of fructose will produce a silver mirror when treated with an ammoniacal solution of silver nitrate (Tol-len s reagent). This is because under basic conditions fructose undergoes tautomerism to glucose, whose structure contains an aldehyde group, which reduces Tollen s reagent to metallic silver. 

The physical properties and many chemical properties of monosaccharides depend on the molecular shape. Equilibria of pyranoid compounds depend largely upon the axial-equatorial relationship between substituents on the rings. Thus, the alp ratio of pyranoses is governed to some extent by the tendency of the anomeric hydroxyl group to occupy the less hindered equatorial substituent orientation. 

During the past ten years, the l,6-anhydro-/3-D-hexopyranoses have found wide application in the synthesis of hexoses and their derivatives, and of oligosaccharides, and for polymerization to polysaccharides. They can be used as model compounds in studying the physical and chemical properties of monosaccharides, as has been shown, for example, by nuclear magnetic resonance (n.m.r.) studies, and also by studies of (a) their chiroptical properties, (b) the partial reactivity of hydroxyl groups, and (c) their ability to form complexes. 

The chemistry of carba sugars is quite similar to that of cyclitols both groups lack the latent carbonyl groups of their saccharide counterparts, and therefore fail to exhibit many of the characteristic properties of monosaccharides. Thus carba sugars and cyclitols do not form hydrazones or osazones, nor do they mutarotate, or reduce heavy-metal salts in base, in contrast to their oxidation products, the inososes. 

There is a great variety in structure as well as chemical and physical properties of monosaccharides. There is no single method that is applicable to the qualitative and quantitative analysis of all monosaccharides instead, the method must be chosen according to the chemical and physical characteristics of the solutes of interest. Borate complexes of monosaccharides can be separated using strong (quaternary amine, Q-type) anion-exchange columns. Alternatively, if the monosaccharide is acidic... 

Bachelard, H. S., 1971, Specificity and kinetic properties of monosaccharide uptake into guinea pig cerebral cortex in vitro,]. Neurochem. 18 213-222. 

A series of physicochemical properties of monosaccharides can be explained only by the conformation formulas Reeves formulas). 

Carbohydrates Chiral Molecules Fischer Projections of Monosaccharides Haworth Structures of Monosaccharides Chemical Properties of Monosaccharides Disaccharides Polysaccharides... 

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