Fructose chemical structure

Fig. 2.5.9 COSY spectra acquired at 600 MHz with an eight-coil probe along with the chemical structures of the compounds used. Each sample was a 10 mM solution in D20 loaded into the coil via the attached Teflon tubes, with the samples being (A) sucrose, (B) galactose, (C) arginine, (D) chloroquine, (E) cysteine, (F) caffeine, (G) fructose and (H)...

How does the chemical structure of the monosaccharide glucose differ from that of the monosaccharide fructose ... 

Figure 4-5 Methods of Representation of D-Fructose. Source From M.L. Wolfrom, Physical and Chemical Structures of Carbohydrates, in Symposium on Foods Carbohydrates and Their Roles, H.W. Schultz, R.F. Cain, and R.W. Wrolstad, eds., 1969, AVI Publishing Co.

Fig. 1 Chemical structures of di-D-fructose dianhydrides (1-7 and 9-14) and of a D-fructose-D-glucose mixed dianhydride (8), with indication of the preferred conformation of six-membered rings...

Two compounds can have different structures because of a differing arrangement of the some groups in the positional isomerism (e.g. midine vs. pseudouridine). Compounds with the same molecular formula but with different functional groups are structural isomers (e.g. D-glucose vs. D-fructose) in structural isomerism. Positional isomers and structural isomers have different chemical and physical properties because of the different arrangement of the atoms. These two types of isomers (i.e. positional isomers and structural isomers), which differ in the manner in which atoms are connected or bonded together, are also called constitutional isomers. 

The composition of reducing sugars in aqueous solution has been surveyed. A review on the structural properties of the anomeric centre in pyranoses and pyranosides has appeared. Three reviews concerning properties of fructose have been published, dealing with its metabolism, its chemical structure and properties, and its chemistry with some emphasis on the relationship between molecular structure and calculated and experimental values of optical activity, and such properties as taste. The production of nutritive sweeteners by acidic and enzymic hydrolysis of starch has been reviewed. ... 

J. C. Norrild, H. Eggert, Boronic acids as fructose sensors. Structure determination of the complexes involved using (1) J(C-C) coupling constants, Journal of the Chemical Society - Perkin Transactions 2 1996, 2583. 

Figure 9.3 Sugar-responsive hydrogel based on the interaction between boronic acid-appended poly(acrylic acid) (pAA-BA) and the polysaccharide schizophyllan (SPG), (a) Chemical structures of pAA-BA and SPG and an illustration of their binding, (b) Photographs of hydrogel prepared from pAA-BA and SPG and its fructose responsiveness. (Reproduced by permission of Chemical Society of Japan.)...

Fig. 5 Chemical structures of simplest fructose-containing oligosaccharides present in GM potatoes in which the 1-SST gene or both 1-SST and 1-FFT genes were expressed...

Carbohydrates are polyhydroxy aldehydes such as glucose, polyhydroxy ketones such as fructose, and compounds such as sucrose formed by linking polyhydroxy aldehydes or polyhydroxy ketones together (Section 21.15). The chemical structures of carbohydrates are... 

Invert sugar—When a solution of sugar is heated in the presence of an acid or treated with enzymes, the sugar breaks up into the two sugars of simpler chemical structure that characterize sucrose as a disaccharide. One is glucose, commercially called dextrose. The other is fructose, commercially... 

Figure 11.7 Chemical structure of the three common "single sugars or monosaccharides, (a) Glucose, (b) galactose, and (c) fructose.

Sugars are either mono- or disaccharides. Monosaccharides include glucose, fructose, galactose, and ribose, and differ in chemical structure. Because the chemistry of saccharides is quite complicated, we shall discuss only the most important aspects that are needed from the pol5mier chemistry point of view. Monosaccharides are the building blocks of disaccharides such as sucrose, and polysaccharides such as cellulose and starch. The chemical structure in an open form can be represented as shown in Figure 5. 2. 

Therapeutic Function Fluid and nutrient replenisher Chemical Name Fructose Common Name Levulose and fruit sugar Structural Formula h... 

Manley-Harris and Richards (Missoula, Montana) have compiled a comprehensive account of the dianhydrides of D-fructose and related compounds, more than 30 in all. These compounds, several of which are of importance in the sugar industry, have in the past presented significant problems in their chemical characterization. Their chemistry was surveyed as early as 1945 by McDonald in Volume 2 of this series, and discussed again in Volume 22 by Verstraeten. The current article furnishes detailed NMR data for each of the anhydrides, providing definitive reference data for accurate identification and correlation with earlier literature, where erroneous structural attributions are rather frequent. 

Although the chemical formulas indicate that ribose is a pentose and fructose is a hexose, the ring portions of the structures are the same size. Proceeding clockwise around the rings from the oxygen atom, we see that the structures differ at the first two positions. In the first position, ribose has a carbon atom bonded to —H and —OH, while)S-fructose has a carbon bonded to —OH and — CH2 OH. In the second position the molecules have the same two bonds but in different orientations. The OH group points up in y6-fructose and down in ribose. The two molecules have the same structures at the other positions. 

Competitive reduction of Au(III) and Ag(I) ions occurs simultaneously in solution during exposure to neem leaf extract leads to the preparation of bimetallic Au-core/Ag-shell nanoparticles in solution. TEM revealed that the silver nanoparticles are adsorbed onto the gold nanoparticles, forming a core/sheU structure. Panigrahi et al. [121] reported that sugar-assisted stable Au-core/Ag-shell nanoparticles with particles size of ca. 10 nm were prepared by a wet chemical method. Fructose was found to be the best suited sugar for the preparation of smallest particles. 

By 1920, it was recognized that a successful chemical synthesis would probably require the use of a D-fructose maintained in the proper cyclic structure by the presence of substituents. The substituent groups would have to be stable enou to survive the conditions required in condensation with a suitable D-glucose derivative, but at the same time be capable of ready removal by agents that failed to affect any sucrose... 

Compounds that have the same chemical formula but have different structures are called isomers. For example, fructose, glucose, mannose, and galactose are all isomers of each other, having the same chemical formula, C6H1206. If two monosaccharides differ in configuration around only one specific carbon atom (with the exception of the carbonyl carbon, see anomers below), they are defined as epimers of each other. (Of course, they are also isomers ) For example, glucose... 

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. 

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