NMR spectroscopy bases

The two major advantages of 3H-NMR spectroscopy based on the characteristic magnetic features of the tritium nucleus are, namely ... 

The structure of the organolithium compound 89 in solution, obtained on metaUation of a cyclic aldonitrone (88), according to equation 29, seems to have the resonant structure (89), as determined by C, N and Li NMR spectroscopy. Based on the spectroscopic evidence and ab initio calculations (MP2/6-31 + G ) on a simplified model compound (H... 

J. L. Griffin, L. A. Walker, S. Garrod, E. Holmes, R. F. Shore and J. K. Nicholson, NMR spectroscopy based metabonomic studies on the comparative biochemistry of the kidney and urine of the bank vole (clethrionomys glareolus), wood mouse (Apodemus sylvaticus), white toothed shrew (Crocidura suaveolens) and the laboratory rat, Comparative Biochemistry and Physiology. Part B, Biochemistry and Molecular Biology, 2000, 127, 357-367. 

Yap et al. investigated a population of biomarkers that might relate the difference in CVD risk between southern and northern Chinese population by 1H NMR spectroscopy-based metabolome-wide association approach (21). The study was carried out among 4680 men and women ages 40-59 years from 17 diverse population samples in China, Japan, United Kingdom, and United... 

Oxidation of a solution of 3-alkyl(aryl)-l,2,4,5-tetrazines in liquid ammonia with permanganate proved to be an excellent route for preparing 6-amino-l,2,4,5-tetrazines (Scheme 30) (81JHC123). The covalent a-adduct, i.e., amino-dihydro-1,2,4,5-tetrazine, is intermediate, as proved by NMR spectroscopy. Based on model studies of 3-phenyl-1,6-dihydro-1,2,4,5-tetrazine, this non-isolable amino-dihydro-1,2,4,5-tetrazine has been characterized as having a homotetrazole structure A (Scheme 30) (81JOC3805). 

Dr. Schroeder s research aims to develop NMR spectroscopy-based approaches that complement or enhance traditional methodology by enabling detailed characterization of small molecule metabolites in complex biological samples, with regard to both chemical structure and biological function. His current work focuses on a comprehensive structural and functional annotation of the metabolome of the model organism Caenorhabditis elegans. 

Moreover, the microstructure of the norbornene homopolymer that is formed using this multi-component catalyst is identical to that produced by naked nickel as evidenced by and NMR spectroscopy. Based on these observations, it is clear that the active catalyst formed in situ from the multi-component system is very similar to the naked nickel single component catalyst [50]. 

Special geometric descriptors for proton NMR spectroscopy based on a local RDF descriptors for a proton. 

The authors have studied the tetranuclear complex Zr (OH) in aqueous solution using NMR spectroscopy. Based on these data they suggest that the stoichiometry of the complex is [Zr4(OH)g(OH2) (OH ), where (0112 and (OH2) denote two different sites of the coordinated water that differ by their rate of exchange of protons with the bulk water. The authors also note the extremely slow rates of exchange of both water and hydroxide with the water solvent, a feature that is much more pronounced than in the less hydrolysed Th(IV). 

Further support for the nonclassical structure of the 2-norbomyl cation came from an application of NMR spectroscopy based on the difference of the total chemical shift of a carbocation and the corresponding alkane. Differences in total chemical shift of 350 ppm or more suggest classical carbocations, while differences... 

M. Bayet-Robert, S. Lim, C. Barthomeuf, and D. Morvan, Biochemical disorders induced by cytotoxic marine natural products in breast cancer cells as revealed by proton NMR spectroscopy -based metabolomics. Biochem. Pharmacol, 80 (2010) 1170-9. 

Danielsen ER and Henriksen O (1994) Absolute quantitative proton NMR spectroscopy based on the amplitude of the local water suppression pulse. Quantification of brain water and metabolites. NMR in Biomedicine 7 311-318. 

I. Barba, R. Fernandez-Montesinos, D. Garcia-Dorado and D. Pozo, Alzheimer s Disease beyond the Genomic Era Nuclear Magnetic Resonance (NMR) Spectroscopy-Based Metabolomics , J. Cell. Mol. Med., 2008, 12, (A5), 1477. 

Dumas, M. E., E. C. Maibaum, C. Teague, H. Ueshima, B. Zhou, J. C. Lindon, J. K. Nicholson, J. Stamler, P. Elliott, Q. Chan and E. Holmes (2006). Assessment of analytical reproducibility of IH NMR spectroscopy based metabonomics for large-scale epidemiological research the INTERMAP Anal Chem 7S(7) 2199-208. 

Maher, A. D., S. F. Zirah, E. Holmes and J. K. Nicholson (2007). Experimental and analytical variation in human urine in IH NMR spectroscopy-based metaboUc phenotyping studies. ... 

Unlike most other characterization techniques introduced in this chapter that only allow conclusions to be drawn on the bulk level, self-diffusion NMR gives detailed information on colloidal systems by focussing on the molecular level. This complex technique will therefore be introduced in detail. NMR spectroscopy, based on physical properties of the molecular spin, is a very powerful method for the measurement of self-diffusion of small molecules in complex solution [67] with direct insight into general aspects of the solution structure [68]. 

P. C. Geiszler, D. P. Auer and C. A. Daykin, The Journey from Metabolic Profiling to Biomarkers The Potential of NMR Spectroscopy Based Meta-bolomics in Neurodegenerative Disease Research, Curr. Metabolomics, 2013, 1, 160. 

UcceUo-Barretta G, Bardoni S, Balzano F, Salvador P. Versatile chiral auxiliaries for NMR spectroscopy based on carbamoyl derivatives of dihydroquinine. Tetrahedron Asymm. 2001 12 2019-2023. 

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