Solution nuclear magnetic resonance

The pKa values of 4-hydroxypyridine 1-oxide (51 52) and the methylated derivatives of both tautomeric forms indicate that the parent compound exists as a mixture containing comparable amounts of both forms in aqueous solution. Nuclear magnetic resonance spectra support this conclusion, but the ultraviolet spectra of the tautomeric compound and both alkylated derivatives are too similar to give information concerning the structural nature of the former. ... 

A recent review of the detergent literature indicated the following trends (1) improvement in dodecyl maltoside surfactants (73), (2) expansion of the use of Triton detergents in biochemistry (74), and (3) the use of detergents for solution nuclear magnetic resonance studies (75). 

He, Q., Richter, W., Vathyam, S. and Warren, W. S. Intermolecular multiple-quantum coherences and cross correlations in solution nuclear magnetic resonance, J.Chem.Phys., 98 (1993),6779-6800... 

Pellecchia, M. (2005) Solution nuclear magnetic resonance spectroscopy techniques for probing intermolecular interactions. Chem. Biol. 12, 961-971. 

M. Jaseja, R. N. Rej, F. Sauriol, and A. S. Perlin, Novel regio- and stereoselective modifications of heparin in alkaline solution. Nuclear magnetic resonance spectroscopic evidence, Can. J. Chem., 67 (1989) 1449-1456. 

Silver(I) ions have been observed to form complexes with benzene in aqueous solution. Nuclear magnetic resonance and solubility studies of aqueous silver nitrate-benzene mixtures established the presence of the cations [(CeHe)Ag]+ and [(CeHe)Ag2]+ (10. 164). 

The second objective Is to examine the Influence of reversed micellar solution parameters, Including the Interaction of substrates with the surfactant Interface, on observed Initial rate kinetics. This Is of Interest because a number of reports have Indicated that enzymes In reversed micellar solutions exhibit an enhanced reactivity, or "super-activity" (7-9I. As a model system, the hydrolysis reactions of synthetic substrates of a-chymotrypsln were studied In a reversed micellar solution. Nuclear magnetic resonance was used to examine the Interactions between these substrates and the micellar environment. 

For water, acetone and methanol solutions, nuclear magnetic resonance studies24 have shown that the coordination number of Mg2+ is 6, although inliquid ammonia25 it appears to be 5. The [Mg(H20)6]2 + ion is not acidic and in contrast to [Be(H20)4]2 + can be dehydrated fairly readily it occurs in a number of crystalline salts. 

In solutions, nuclear magnetic resonance is of use from the H paramagnetic shift (AAv) of a reference compound, corrected for the diamagnetic contribution of the ligands, the paramagnetic susceptibility is evaluable using the Evans method [10]... 

Table 2.1. Chemical shift references for biological phosphorus compounds in solution nuclear magnetic resonance spectroscopy. Bold type indicates general peak shift ranges regular type indicates specific chemical shift assignments.

Table 2.3. Solution nuclear magnetic resonance (NMR) methodology papers for environmental samples.

Table 2.5. Studies of phosphorus in forest soils using whole-soil extractions and solution nuclear magnetic resonance spectroscopy.

Details of the forms of organic phosphorus that occur in the environment can be found in several published reviews (e.g. Dalai, 1977 Anderson, 1980 Harrison, 1987) and elsewhere in this volume, but a brief overview is provided here. Advances in solution nuclear magnetic resonance spectroscopy... 

Solution nuclear magnetic resonance (NMR) spectroscopy was introduced by Newman and Tate (1980) to define the structural composition of soil organic phosphorus. The technique allows the identification of several inorganic phosphorus forms (phosphate, pyrophosphate, polyphosphate) and organic phosphorus forms, such as phosphate monoesters (e.g. inositol phosphates and sugar phosphates), phosphate diesters (e.g. nucleic acids, phospholipids, teichoic acids) and phosphonates. 

Table 11.2. Application of solution nuclear magnetic resonance spectroscopy to topsoil samples from agroecosystems in the tropics. 

Fig. 12.3. The phosphorus composition of broiler litter from a farm in Delaware, USA, determined by extraction with a solution containing sodium hydroxide and ethylenediaminetetraacetate (EDTA) and solution nuclear magnetic resonance spectroscopy. The extract contained 97% of the total phosphorus in the litter, of which 40% was phosphate and 60% was myo-inositol hexakisphosphate (phytic acid). Traces of pyrophosphate were also detected. The inset spectrum shows the four signals from myo-inositol hexakisphosphate, corresponding to the positions of the phosphates on the inositol ring (C-1 to C-6). Details of analytical methodology can be found in Turner (2004).

FIGURE 9.39 Phosphorus forms as determined by solution nuclear magnetic resonance spectroscopy (Tnmer et al., 2004). 

Reprinted with permission from Buddrus et al. Quantitation of Partial Structures of Aquatic Humic Substances by One- and Two-Dimensional Solution Nuclear Magnetic Resonance Spectroscopy," Anal. Chem. 61, 628-631. Copyright 1989, American Chemical Society. 

Van Horn WD, Kim HJ, Ellis CD, Hadziselimovic A, Sulistijo ES, Karra MD, Tian C, Sonnichsen FD, Sanders CR (2009) Solution nuclear magnetic resonance structure of membrane-integral diacylglycerol kinase. Science 324 1726-1729... 

Page RC, Moore JD, Nguyen HB, Shatma M, Chase R, Gao FP, Mobley CK, Sanders CR, Ma L, Sonnichsen FD, Lee S, Howell SC, Opella SJ, Cross TA (2006) Comprehensive evaluation of solution nuclear magnetic resonance spectroscopy sample preparation for helical integral membrane proteins. J Struct Funct Genomics 7 51-64... 

Standard laboratory practices and procedures were followed. Eye protection and a functioning fume hood, glassware, magnetic and mechanical stirrers, chromatography columns and column materials, rotary evaporator, and vacuum pump were required. Chemicals for syntheses were either commercially available or synthesized by following the standard reported procedures. Compounds were routinely checked by solution nuclear magnetic resonance spectroscopy (NMR) and other appropriate spectroscopic and analytical methods. 

R35 C. B. Kang and Q. Li, Solution Nuclear Magnetic Resonance Study of Integral Membrane Proteins , Curr. Opin. Chem. Biol., [online computer file], 2011, 15, 560. 

R98 T. M. A. Blumenschein, Biomolecular Structures by Solution Nuclear Magnetic Resonance , in Encyclopedia of Applied Spectroscopy, ed. D. L. Andrews, Wiley-VCH Verlag GmbH Co. KGaA, Weinheim, Germany, 2009, p. 963. 

R120 M.-J. Clement, P. Savarin, E. Adjadj, A. Sobel, F. Toma and P. A. Curmi, Probing Interactions of Tubulin with Small Molecules, Peptides, and Protein Fragments by Solution Nuclear Magnetic Resonance , in Methods in Cell Biology, eds. L. Wilson and J. J. Correia, Elsevier Inc., 2010, Vol. 95, Microtubules, in vitro, p. 407. 

Regiostructures for soluble poly(CHD) and its copolymers are determined by solution nuclear magnetic resonance (NMR) spectroscopy. For the poly(CHD) unit, the Ho, Ha, and Hb protons (Figure 18.2) are identified with signals at, respectively, 5.73, 2.01, and 1.56 ppm. There are equal numbers of Ho and Ha protons in the 1,4-unit of poly(CHD), while the ratio of Ho to Ha protons in the 1,2-unit is 2 3. Therefore, regioregularity can be estimated by the Ho/Ha integral value ratio. 

PCy3)2(C02) a comparative solid-state-solution nuclear magnetic resonance study ( P, C) as a diagnostic tool to determine the mode of bonding of CO2 to a metal center. Inorg Chem 31 4286-4290... 

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