Carbohydrate nuclear magnetic resonance

Present day techniques for structure determination in carbohydrate chemistry are sub stantially the same as those for any other type of compound The full range of modern instrumental methods including mass spectrometry and infrared and nuclear magnetic resonance spectroscopy is brought to bear on the problem If the unknown substance is crystalline X ray diffraction can provide precise structural information that m the best cases IS equivalent to taking a three dimensional photograph of the molecule... 

Monomer (Section 6 21) The simplest stable molecule from which a particular polymer may be prepared Monosaccharide (Section 25 1) A carbohydrate that cannot be hydrolyzed further to yield a simpler carbohydrate Monosubstituted alkene (Section 5 6) An alkene of the type RCH=CH2 in which there is only one carbon directly bonded to the carbons of the double bond Multiplicity (Section 13 7) The number of peaks into which a signal IS split in nuclear magnetic resonance spectroscopy Signals are described as singlets doublets triplets and so on according to the number of peaks into which they are split... 

The proton spin-lattice relaxation-rate (R,) is a well established, nuclear magnetic resonance (n.m.r.) parameter for structural, configurational, and conformational analysis of organic molecules in solution. " As yet, however, its utility has received little attention in the field of carbohydrate chemistry,... 

NATURAL-ABUNDANCE, 13C-NUCLEAR MAGNETIC RESONANCE-SPECTRAL STUDIES OF CARBOHYDRATES LINKED TO AMINO ACIDS AND PROTEINS... 

Vliegenthart, J.F.G., Dorland, L., and van Halbeek, H. (1983) High-resolution, lH-nuclear magnetic resonance spectroscopy as a tool in the structural analysis of carbohydrates related to glycoproteins. Adv. Carbohydr. Chem. Biochem. 41, 209-374. 

The value of H n.m.r. spectroscopy in determining the structures of carbohydrates is well recognized. In this Section, some of the important features observed in the 100-MHz, H n.m.r. spectra of sucrose derivatives will be discussed, and the potential of I3C nuclear magnetic resonance spectroscopy will be very briefly indicated. Horton and his colleagues162 discussed the high resolution, 4H n.m.r. spectra of octa-O-acetylsucrose (75). The chemical shifts and cou-... 

Vittadini, E., Dickinson, L.C., and Chinachoti, P. 2002. NMR water mobility in xanthan and locust bean gum mixtures Possible explanation of microbial response. Carbohydr. Polym. 49, 261-269. Wachner, A.M. and Jeffrey, K.R. 1999. A two-dimensional deuterium nuclear magnetic resonance study of molecular reorientation in sugar/water glasses. J. Chem. Phys. Ill, 10611-10616. Wagner, W. and Pruss, A. 1993. International equations for the saturation properties of ordinary water substance Revised according to the international temperature scale of 1990. J. Phys. Chem. Ref. Data 22, 783-787. 

While the broad mission of the National Bureau of Standards was concerned with standard reference materials, Dr. Isbell centered the work of his laboratory on his long interest in the carbohydrates and on the use of physical methods in their characterization. Infrared spectroscopy had shown promise in providing structural and conformational information on carbohydrates and their derivatives, and Isbell invited Tipson to conduct detailed infrared studies on the extensive collection of carbohydrate samples maintained by Isbell. The series of publications that rapidly resulted furnished a basis for assigning conformations to pyranoid sugars and their derivatives. Although this work was later to be overshadowed by application of the much more powerful technique of nuclear magnetic resonance spectroscopy, the Isbell— Tipson work helped to define the molecular shapes involved and the terminology required for their description. 

Structural investigations into the degree of branching and into the position and nature of glycosidic bonds and of non-carbohydrate residues in polysaccharides may include periodate oxidation and other procedures such as exhaustive methylation. X-ray diffraction and spectroscopic techniques such as nuclear magnetic resonance and optical rotatory dispersion also give valuable information especially relating to the three-dimensional structures of these polymers. 

The next chapter, by Ren Csuk and Brigitte I. Glanzer (Zdrich), constitutes an extensive treatise on the nuclear magnetic resonance (n.m.r.) spectroscopy of fluorinated monosaccharides [whose early chemistry was surveyed in Vol. 38 (1981) by Anna A. E. Penglis] the comprehensive data tabulated herein should be especially of value to those working in the fleld. It continues the coverage, in Advances, of n.m.r. spectroscopy as the key tool for characterization of carbohydrates. It complements articles on the H-n.m.r. spectroscopy of carbohydrates by Laurance D. Hall [Vols. 19 (1964) and 29 (1974)], Bruce Coxon [Vol. 27 (1972)], and Johannes F. G. Vliegenthart, Lambertus Dorland, and Herman van Halbeek [Vol. 41 (1983)], and on the C-n.m.r. spectroscopy of monosaccharides by Klaus Bock and Christian Pedersen [Vol. 41... 

Duus J0, Gotfredsen CH, Bock K (2000) Carbohydrate Structural Determination by NMR Spectroscopy Modem Methods and Limitations. Chem Rev 100 4589 Agrawal PK, Pathak AK (1996) Nuclear Magnetic Resonance Spectroscopic Approaches for the Determination of friterglycosidic Linkage and Sequence in Oligosaccharides. Phytochem Anal 7 113... 

Gidley, M. (1992). Nuclear magnetic resonance analysis of cereal carbohydrates. In R. J. Alexander, H. F. Zobel (Eds.), Developments in Carbohydrate Chemistry (pp. 163-192). The American Association of Cereal Chemists, St. Paul, Minnesota. 

An important complementary method for determining the three-dimensional structures of macromolecules is nuclear magnetic resonance (NMR). Modern NMR techniques are being used to determine the structures of ever-larger macromolecules, including carbohydrates, nucleic acids, and small to average-sized proteins. An advantage of NMR studies is that they are... 

Because nuclear magnetic resonance (NMR) is particularly advantageous for carbohydrates, protecting group routes may often be shortened by the use of partial substitution reactions [4-6], followed by chromatographic separations and characterization by means of NMR. 

Since the publication of the first application of nuclear magnetic resonance to carbohydrates,848 it has become almost standard practice, in discussing many carbohydrate topics, to include nuclear magnetic resonance data. The subject has been reviewed.348... 

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