Glucose in aqueous solution

Sorbitol is manufactured by the reduction of glucose in aqueous solution using hydrogen with a nickel catalyst. It is used in the manufacture of ascorbic acid (vitamin C), various surface active agents, foodstuffs, pharmaceuticals, cosmetics, dentifrices, adhesives, polyurethane foams, etc. 

You can detect hydroxyl group transitions by plotting dihedral angles versus time over the course of the simulation. This is the distance history. Brady investigated the distance history of water 19. Brady, J.W. Molecular dynamics simulations of a-d-glucose in aqueous solution. 

One of the best-known systems involving epimerization is that of d-glucose. In aqueous solution the epimeric a- and 0-forms are in equilibrium, but each can be obtained by crystallization ethanol readily affords the pure a-form, whereas pure 0 may be obtained from pyridine. 

Assignments of the frequencies observed187 in the spectra of D-glucose in aqueous solutions permitted determination, from the ratio of intensities of characteristic modes of vibrations, of the proportions of a and f3 anomers at equilibrium, which were 32 and 68%, respectively. The particular behavior... 

P. E. Morris, Jr., K. D. Hope and D. E. Kiely, The isomeric composition of D-ribo-hexos-3-ulose (3-keto-D-glucose) in aqueous solution, J. Carbohydr. Chem., 8 (1989) 515-530. 

Figure 4-3 Tautomeric Forms of Glucose in Aqueous Solution at Room Temperature...

Da Silva et al. " computed the optical rotation of three a and five p conformations of D-glucose in aqueous solution using a TDDFT/GLAO approach with either the aug-cc-pVDZ or 6-31-l-l-G(d,p) basis sets. The a conformations aU have large positive values of [a]o, while the P conformations have values that range from -10° to -1-80°. The Boltzmann-weighted average value is 62.6° or 58.8° with the aug-cc-pVDZ or 6-31-l-l-G(d,p) basis sets, respectively. These values are reasonably close to the experimental value of 52.T For those interested, Mennucci et al. have reviewed the application of computational models of solvent effects on chiroptical properties. 

M. A. Arnold, G. Small, and L. A. Marquart, Temperature-Insensitive Near-Infrared Spectroscopic Measurement of Glucose in Aqueous Solutions, Appl. Spectrosc., 48(4), 477 (1994). 

The forms of glucose in aqueous solution are quite complex and small proportions exist as furanose structures. These arise from the reaction between the OH group at C-4 and the aldehyde group in aldoses. The five-membered ring system is quite stable but pyranose forms are favoured over furanose forms by most monosaccharides notable exceptions are the ketohexose fructose and the aldopentose ribose. Too much strain would be involved in reducing bond angles to produce smaller rings, so trioses and tetroses do not form intermolecular cyclic systems. 

A possible variation of the concerted mechanism includes a dimeric water molecule as a bifunctional catalyst (see Fig. 10). Another concept concerning the role of water molecules has been developed by Schmid.254 He suggested an activated complex of the type (BH . .. H20. .. G ), where B is a base, and G is a D-glucosyloxy anion. In the hydrogen-ion-catalyzed mutarotation of D-glucose in aqueous solutions, H20 acts as a base to remove H30 , and the activated complex is D-glucose ...H20...H30 . 

The isomerisation of glucose in aqueous solution can be used to illustrate this. 

CAicohoi Content of alcohol in aqueous solution CutoH Content of ethanol in aqueous solution Glucose Content of glucose in aqueous solution Chxoh Content of hexanol in aqueous solution CMeOH Content of methanol in aqueous solution CNaci Content of sodium chloride in aqueous solution cprOH Content of 1-propanol in aqueous solution... 

Consider next the fermentation of some nonnitrogenous, but otherwise unspecified, substrate (for example, a sugar such as glucose) in aqueous solution with dissolved ammonia as the nitrogen source to produce average biomass, carbon dioxide, and water. On a carbon mole basis, this reaction is... 

Figure 15.19 The structure of glucose in aqueous solution and the formation of a disaccharide. A, A molecule of glucose undergoes an internal addition reaction between the aldehyde group of C-1 and the al-...

Molteni, C., Parrinello, M. (1998). Glucose in aqueous solution by first principles molecular dynamics, J. Am. Chem. Soc., 120 2168. 

An electrochemical method involving electrocatalytic oxidation with TEMPO was suitable for the determination of glucose in aqueous solution. The cyanine dye 2, which carries two phenylboronic acid moieties displays increased fluorescence on binding to monosaccharides and provides a novel detection method. Compound 3 also contains a phenylboronic acid residue and binds D-glucose 6-... 

Hazen, K. H., Arnold, M. A. and Small, G. W. (1994) Temperature-insensitive near-infrared spectroscopic measurement of glucose in aqueous solutions. Applied Spectroscopy, 48,477-83. Hecht-Nielsen, R. (1989) Neurocomputing, Addison-Wesley, Reading, MA. 

Show that the percentages of a- and /S-D-glucose in aqueous solution at equilibrium can be calculated from the specific rotations of the pure a and )8 forms and the specific rotation of the solution at equilibrium. 

The tautomeric equilibria of aldopentoses, aldohexoses and hexuloses in DMSO have been examined by C-n.m.r. spectroscopy the mutarotation kinetics of aqueous D-glucose have been investigated by i.r. methods, and Raman spectroscopic data on the tautomeric transformations of glucose in aqueous solution over a wide pH range confirmed that the ring-chain tautomerism depends on pH." The ring shapes of the two fiiranose and two pyranose forms of psicose in aqueous solution, riiown by n.m.r. spectroscopy to be present in almost equal proportions, have been analyzed by MM3."... 

D. B. Cordes, S. Gamsey and B. Singaram, Fluorescent quantum dots with boronic acid substituted viologens to sense glucose in aqueous solution, Angem Chem., Int. Ed., 2006,45(23), 3829-3832. 

Figure 15.19 A, The structure of glucose in aqueous solution. B, The formation of a disaccharide.

Anomerizatlon of D-glucose in aqueous solution has been monitored by F.t.l.r., many bands being identified specifically with the a-or 3-anomer. D-Rlbose and 2-deoxy-D-rlbose have been examined by both F.t.l.r. and laser-Raman methods, both in solution and in the... 

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