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Quantitative 1H NMR spectroscopy
TrAC Trends in Analytical Chemistry, 2012Abstract This review illustrates the need to use nuclear magnetic resonance (NMR) spectroscopy for the quantitative analysis of small molecules in their crude forms and in mixtures. We provide the basic concepts of quantitative NMR (qNMR), a brief description of important acquisition and processing parameters responsible for obtaining high-quality ...
Santosh Kumar Bharti, Raja Roy
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2009
Electronegative substituents cause a decrease in |J|gem while a double or triple bond next to the CH2 group causes an increase.
Ernö Pretsch +2 more
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Electronegative substituents cause a decrease in |J|gem while a double or triple bond next to the CH2 group causes an increase.
Ernö Pretsch +2 more
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The 1H NMR spectrum of benzanthrone
Spectrochimica Acta Part A: Molecular Spectroscopy, 1981Abstract The chemical shifts of all the eleven protons in the 1 H NMR spectrum of benzanthrone have been assigned unambiguously.
A.V.Rama Rao, A. Vaidyanathan
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Rubber Chemistry and Technology, 1980
Abstract 1H NMR spectra of polyisoprene were assigned using polymers of isoprene-1,1,4,4-d4, isoprene-1,1,5,5,5-d5, and isoprene-4,4-d2 polymerized with various catalysts. The methylene-proton signal at 2.1 ppm in cis-1,4- and trans-1,4-polyisoprenes was divided into H4- and H1-proton signals; H4 resonated at 2.21 ppm in both cis-1,4
H. Sato, Y. Tanaka
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Abstract 1H NMR spectra of polyisoprene were assigned using polymers of isoprene-1,1,4,4-d4, isoprene-1,1,5,5,5-d5, and isoprene-4,4-d2 polymerized with various catalysts. The methylene-proton signal at 2.1 ppm in cis-1,4- and trans-1,4-polyisoprenes was divided into H4- and H1-proton signals; H4 resonated at 2.21 ppm in both cis-1,4
H. Sato, Y. Tanaka
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1H-NMR of human saliva. An application of NMR spectroscopy in forensic science
Forensic Science International, 19871H-NMR was applied to the study of metabolites in human saliva specimens. Acetate, lactate, ethanol, glucose and some other substances were simultaneously identified and quantitated from the 1H-NMR spectra of saliva specimens treated with D2O. These experiments demonstrated the value of 1H-NMR as an analytical method in the field of forensic science ...
H, Harada, H, Shimizu, M, Maeiwa
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1H-NMR assay of phosphatidylcholine and phosphatidylethanolamine in AL721
Journal of Pharmaceutical and Biomedical Analysis, 1990A 1H-NMR based method has been developed for the assay of phosphatidylcholine (PC), and phosphatidylethanolamine (PE) in AL721. The assay was based on the comparison of NMR signal intensities of the choline and the ethanolamine moiety of PC and PE, respectively, to the signal of imidazole, the internal standard. The assay was reliable and more accurate
A P, Cheung, L L, Olson
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1990
Proton nuclear magnetic resonance (1H-NMR) provides a sensitive means to detect biochemical changes in living systems (Ackerman et al 1981, Gadian 1982). The usefulness of 1H-NMR for in vivo studies has been shown in hypoxia (Behar et al 1983), hypoglycemia (Behar et al 1985), seizures (Petroff et al 1986), and ischemia (Gadian et al 1986, Crockard et ...
G. A. Rosenberg +4 more
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Proton nuclear magnetic resonance (1H-NMR) provides a sensitive means to detect biochemical changes in living systems (Ackerman et al 1981, Gadian 1982). The usefulness of 1H-NMR for in vivo studies has been shown in hypoxia (Behar et al 1983), hypoglycemia (Behar et al 1985), seizures (Petroff et al 1986), and ischemia (Gadian et al 1986, Crockard et ...
G. A. Rosenberg +4 more
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1H-NMR and 13C-NMR Spectral Assignments of Spiramycins I and III
Pharmaceutical Research, 1994The spiramycins (1a-1c) are 16-membered macrolide antibiotics produced by the bacteria Streptomyces ambofaciens (1) (Scheme I). This series of compounds shows gram-positive antibacterial activity as well as antimicrobial activity against both Toxoplasma gondii and Cryptosporidium, two protozoans which can result in potentially fatal opportunistic ...
Ramu, Kumar +4 more
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Complete 1H and 13C NMR spectra of pregnenolone
Steroids, 1995Assignments for signals from 1H and 13C in the NMR spectra of pregnenolone (1), 16-dehydropregnenolone (2), and the 3-acetate of 1 (3) were validated by two-dimensional correlated spectroscopy (2D COSY) and heteronuclear single quantum coherence (HSQC).
Z, Szendi, P, Forgó, F, Sweet
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A 1H NMR study of cobalt(II) arsanilazocarboxypeptidase A
Journal of Inorganic Biochemistry, 1989Cobalt(II) arsanilazotyrosine-248 carboxypeptidase A has been characterized through 1H NMR spectroscopy. The ability of the azoenzyme to form binary and ternary complexes with L- and D-phenylalanine and azide has been investigated. Comparison with the 1H NMR results obtained on unmodified cobalt(II) carboxypeptidase provides direct information on the ...
BERTINI, IVANO +3 more
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