Protons, nuclear magnetic resonance

It is interesting to note that the acyclic analog, nitroguanidine, exists in the symmetrical form 288 rather than as 289. Structure 288 has been established by ultraviolet and proton nuclear magnetic resonance spectroscopy. X-ray crystallography, dipole moments, and ipK measurements (see reference 367 and references therein). 

Proton nuclear magnetic resonance spectra of 15-20% solutions of polymers in CC14 were obtained with Varian T-60 or HR-300 spectrometers. Chemical shifts are reported... 

Spectra. The UV spectra in w, acid, and base are given in Ref 5. The proton nuclear magnetic resonance spectrum shows a sharp singlet at 3.90ppm from te tram ethyl silane (Ref 15)... 

Stuermer, D. H. and Payne, J. R. (1976). Investigation of seawater and terrestrial humic substances with carbon-13 and proton nuclear magnetic resonance. Geochim. Cosmochim. Acta 40,1109-1114. 

Gakh, E.G., Dougall, D.K., and Baker, D.C., Proton nuclear magnetic resonance studies of monoacylated anthocyanins from the wild carrot part 1. Inter- and intramolecular interactions in solution, Phytochem. Anal., 9, 28, 1998. 

Godejohann M, M Astratov, A Preiss, K Levsen, C Miigge (1998) Application of continuous-flow HPLC-proton-nuclear magnetic resonance spectroscopy and HPLC-thermospray spectroscopy for the structrual elucidation of phototransformation products of 2,4,6-trinitrotoluene. Anal Chem 70 4104-4110. 

Grootveld, M.C., Herz, H., Haywood, R, Hawkes, G.E., Naughton, D., Perera, A., Knappitt, J., Blake, D.R. and Claxson A.W.D. (1994). Multicomponent analysis of radio-lytic products in human body fluids using high field proton nuclear magnetic resonance (NMR) spectroscoopy. Radiat. Phys. Chem. 43, 445-453. 

Single-pulse proton nuclear magnetic resonance (NMR) spectroscopy has been used to demonstrate that the mean chain length of synovial fluid triglycerides is shorter than that in corresponding sera (Naughton etal.,... 

Naughton, D., Whelan, M., Smith, E.C., Williams, R., Blake, D.R. and Grootveld, M. (1993). An investigation of the abnormal metabolic status of synovial fluid from patients with rheumatoid arthritis by high field proton nuclear magnetic resonance spectroscopy. FEBS Lett. 317, 135-138. 

T. Iwashita, Y. Mino, H. Naoki, Y. Suguira, and K. Nomoto, High-resolution proton nuclear magnetic resonance analysis of solution structures and conformational properties of muguneic acids and its metal complexes. Biochemistry 22 4842 (1983). 

Ludlow, M., Louden, D., Handley, A., Taylor, S., Wright, B., and Wilson, I.D., Size-exclusion chromatography with on-line ultraviolet, proton nuclear magnetic resonance, and mass spectrometric detection and on-line collection for off-line Fourier transform infrared spectroscopy, /. Chromatogr. A, 857,89,1999. 

FID = flame ionization detection GC = gas chromatography HPLC = high performance liquid chromatography ITMS = ion trap mass spectrometry MS = mass spectrometry PNMR = proton nuclear magnetic resonance TLC = thin-layer chromatography... 

Owens C, Karyannis NM, Pytlewski LL, et al. 1971. Infrared and proton nuclear magnetic resonance studies of adduct of tin(II) and (IV) and titanium(IV) halides with diisopropyl methylphosphonate. Journal of Physical Chemistry 75(5) 637-641. 

Nomier AA, Abou-Donia MB. 1986. Studies on the metabolism of the neurotoxic tri-ort/20-cresyl phosphate Synthesis and identification by infrared, proton nuclear magnetic resonance and mass spectrometry of five of its metabolites. Toxicology 38 1-13. 

The proton nuclear magnetic resonance (NMR) spectra of primaquine diphosphate was obtained using a Bruker instrument operating at 300, 400, or 500 MHz. 

Table 3. Proton nuclear magnetic resonance assignments for spectrum of sodium valproate...

Carborane, Bk>C2Hi2, is quite soluble in aromatic solvents and is sparingly soluble in aliphatic solvents. The infrared spectrum has been previously reported.25 The proton nuclear magnetic resonance spectrum of a chloroform-d3 solution of carborane contains a broad CH resonance at 6.46 t. 

Methylcarborane is an air-stable, white crystalline solid which is soluble in common organic solvents. The infrared spectrum (Nujol mull) contains major absorption bands at 3.90 (s), 8.83 (w), 9.12 (w), 9.69 (w), 9.83 (w), 10.03 (w), and 13.85 (s) p. The proton nuclear magnetic resonance spectrum of a carbon tetrachloride solution of methylcarborane contains a broad —CH resonance of intensity 1 at 6.52 r and a —CH3 resonance of intensity 3 at 8.02 r. 

Tris(dimethylamino)arsine (d2o 1.1248 nd 1.4848)3 is a colorless liquid which is readily hydrolyzed to form arsenic (III) oxide and dimethylamine when brought into contact with water. The compound is soluble in ethers and hydrocarbons. The product is at least 99.5% pure (with respect to hydrogen-containing impurities) as evidenced by the single sharp peak at —2.533 p.p.m. (relative to tetramethylsilane) seen in the proton nuclear magnetic resonance spectrum of the neat liquid. 

Diethylamino)trimethylstannane is a colorless liquid which boils at 36°/6 mm. The compound is quickly hydrolyzed by moisture. The proton nuclear magnetic resonance spectrum of a neat sample shows a CH3—Sn resonance at 9.92 r with HChs—Sn119 splitting of 56.5 cycles and HCh,—Sn117 splitting of 54.0 cycles. The ethyl resonance consists of a triplet at 9.10 r... 

T. Yoshida, H. Okabayashi, K. Takahashi, and I.Ueda, A proton nuclear magnetic resonance study on the release of bound water by inhalation anesthetic in water-in-oil emulsion. Biochim. Biophys. Acta, 772,102-107 (1984). 

Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy ( ll NMR) have become standards for verifying the chemistry of polyanhydrides. The reader is referred to the synthesis literature in the previous section for spectra of specific polymers. The FTIR spectrum for PSA is shown in Fig. 2. In FTIR the absorption... 

Proton nuclear magnetic resonance (NMR) chemical shifts of 1,2,3-thiadiazoles give another indication of the aromatic character of these compounds. Compiled in Table 4 are a number of examples of proton chemical shifts for ring-substituted 1,2,3-thiadiazoles. 

Bell, J. D., Brown, J. C. C., Sadler, P. J. etal. High resolution proton nuclear magnetic resonance studies of human cerebrospinal fluid. Clin. Sci. 72 563-570,1987. 

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