Sucrose, structure

The carbon backbone of the sucrose structure (Figure 3) is almost completely shielded by the o gen and hydrogen atoms and is expected to play only a minor role, if any, in solvent interactions. The relative contact areas of oj gens and hydrogens are orientation dependent and may impart a specific character to the different faces of the sucrose crystal. 

Hehre, Edward J., The Substituted-sucrose Structure of Melezitose, 8, 277-290... 

One of the major points advanced by Kuhn and von Grundherr for the substituted-sucrose structure of melezitose was the extreme ease of acid hydrolysis of one of the linkages, which had earlier led Alekhine to the discovery of turanose and the trisaccharide nature of melezitose. For years this feature was accepted as virtual proof of the presence of sucrose in the melezitose molecule. However, the opinion that the ease of hydrolysis was evidence for the furanoid form of the D-fructose ring lost all validity with the discovery by Purves and Hudson1 that methyl D-fructopyranoside is hydrolyzed by acids with the same ease as methyl D-fructofuranoside moreover, the ease of hydrolysis never was evidence concerning the a- or /3-configuration of the D-fructose unit in melezitose. ... 

K. Capek, M. Vodrazkova-Medonosova, J. Moravlova, and P. Sedmera, Partially acetylated sucrose. Structure of hepta-O-acetylsucroses formed by deactetylation of octa-O-acetylsucrose, Collect. Czech. Chem. Commun., 51 (1986) 1476-1485. 

Sucrose structure showing the three primary hydroxyl groups (6,1, 6 )... 

Sucrose structure in aqueous soiution. The two sugar units are simiiariy disposed towards each other, caused by insertion of a water moiecuie between the giucosyi-2-OH and fructosyi-1-OH groups and the water bridge is fixed by hydrogen bonding. From [20]... 

The hydrogen bond 0 O distance may have a value from 2.68 to 3.04 A. For a complete understanding of the significance of the data, more analyses need to be carried to the same degree of completion as for the sucrose structure, where the neutron-diffraction measurements made possible the precise location of the hydrogen atoms. 

Haynes, L. J., and Nbwth, F. H., The Glycosyl Halides and Their Derivatives, 10, 207-256 Hehrb, Edward J., The Substituted-sucrose Structure of Melezitose, 8, 277-290... 

Figure 3.25 Homonuclear decoupling experiments of the 300 MHz proton NMR spectrum of sucrose dissolved in D2O. The fully coupled spectrum is shown in (c). (a) Selective saturation of the triplet at 4.05 ppm collapses the doublet at 4.22 ppm, showing the coupling between the positions of protons a and b marked on the sucrose structure, (b) Saturation of the doublet at 5.41 ppm collapses the doublet of doublets at 3.55 ppm, leaving a doublet. The experiment shows the coupling between the protons marked c and d on the structure. (The spectra are from Petersheim, used with permission. The sucrose structure is that of D-(- -)-sucrose, obtained from the SDBS database, courtesy of National Institute of Industrial Science and Technology, Japan, SDBSWeb http //www. aist.go.jp/RIOBD/SDBS. Accessed 11/05/02.)...

There are many examples in the literature of the structural characterization of polymeric systems by FD-MS. Some of these will be briefly mentioned here. Saito and coworkers in Japan have studied a number of polymers by FD-MS. FD spectra were used to identify various poly(ethylene glycol) and poly(pro-pylene glycol) initiators (water, ethyleneimine, glycerol, sorbitol, sucrose). Structures of bisphenol A-based epoxy resins were elucidated. The degree of methylation in methylol melamine resins was assessed. Various novalak resins (made from phenol, alkylphenols, and epoxidized phenols) were characterized. Styrene polymerized with various initiators and chain transfer agents was studied in some cases deuterium labeling was used to help... 

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