Nuclear magnetic resonance one-dimensional

Balcom, B Fischer, A Carpenter, T Hall, L, Diffusion in Aqueous Gels. Mutual Diffusion Coefficients Measured by One-Dimensional Nuclear Magnetic Resonance Imaging, Journal of the American Chemical Society 115, 3300, 1993. 

Fig. 2.3. Outline of a conventional one-dimensional nuclear magnetic resonance experiment, (a) A sample in a nuclear magnetic resonance tube (b) a magnet into which the sample is placed (c) the outline of a simple experiment (d) the free induction decay (FID), which is Fourier-transformed to a spectrum (e).

Previously, only one-dimensional nuclear magnetic resonance (NMR) spectroscopic data had been reported for the 3,6-anhydroglucal 7 in the literature [17]. We carried out additional two-dimensional NMR experiments ( H- H COSY, NOESY, and HMQC) to fully characterize the compound. The proposed anhydro structure was supported by the observation of long-range coupling between the vinylic proton (C2) and the bridgehead proton (C4 1.5 Hz). We were also able to obtain crystals for 3,6-anhydroglucal 7 and an x-ray structure was obtained [26]. 

This well-rounded introduction features updated spectra, a modernizedpresentation of one-dimensional Nuclear Magnetic Resonance (NMR) spectroscopy, the introduction of biological molecules in mass spectrometry, and inclusion of modern techniques alongside DEPT, COSY, and HECTOR. Count on this book s exceptional presentation to provide the comprehensive coverage needed to truly understand today s spectroscopic techniques. 

Giusti, M.M., Ghanadan, H., and Wrolstad, R.E., Elucidation of the structure and conformation of red radish Raphanus sativus) anthocyanins using one- and two-dimensional nuclear magnetic resonance techniques, J. Agric. Food Chem., 46, 4858, 1998. 

Servili M, Baldioli M, Selvaggini R, Macchioni A and Montedoro GF. 1999. Phenolic compounds of olive fruit one and two-dimensional nuclear magnetic resonance characterization of niizhenide and its distribution in the constitutive parts of fruit. J Agric Food Chem 47(1) 12—18. 

The structures of vanicosides A (1) and B (2) and hydropiperoside (3) were established primarily by one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy techniques and fast atom bombardment (FAB) mass spectrometry (MS).22 The presence of two different types of phenylpropanoid esters in 1 and 2 was established first through the proton (4H) NMR spectra which showed resonances for two different aromatic substitution patterns in the spectrum of each compound. Integration of the aromatic region defined these as three symmetrically substituted phenyl rings, due to three p-coumaryl moieties, and one 1,3,4-trisubstituted phenyl ring, due to a feruloyl ester. The presence of a sucrose backbone was established by two series of coupled protons between 3.2 and 5.7 ppm in the HNMR spectra, particularly the characteristic C-l (anomeric) and C-3 proton doublets... 

Kosir, I. and Kidric, J. (2001). Identification of amino acids in wines by one- and two-dimensional nuclear magnetic resonance spectroscopy. ]. Agric. Food Chem. 49, 50-56. 

The structure and identity of such compounds that are of practical relevance as com-plexing agents may be elucidated unequivocally by both one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy of the isotopes H-l, C-13, and P-31. Sufficiently high concentrations also render possible their quantitative analysis [87-91]. However, because of the low sensitivity, especially of the phosphorus nucleus, problems are encountered with the limits of detection in practical applications. 

Pathway calculations for the aforementioned intramolecular ET reaction were performed using the high-resolution 3D structures of P. aeruginosa azurin and its mutants, where available. For other mutants, structures based on two-dimensional nuclear magnetic resonance (2D NMR) studies and energy minimization calculations were employed. The pathway calculations predict similar ET routes in all the azurins shown in Fig. 4 One longer path through the peptide... 

HS was extracted from the labeled SRS soils with 0.25 M NaOH following our previous procedure (23). The isolated HS was then subjected to multinuclear, one and two dimensional nuclear magnetic resonance... 

As a qualitative means to investigate the ionic nature of acid-base systems, various techniques have been employed such as one- or two-dimensional nuclear magnetic resonance (NMR) spectroscopy [31], infrared (IR) spectroscopy [32], the Walden plot [33], the ratio of molar conductivities AjmpMNMR (determined by electrochemical impedance spectroscopy and pulse-field-gradient spin-echo NMR, respectively) [34], Some of these will be discussed below. 

J. Leisen, M. Werth, C. Boeffel, and H. W. Spiess, Molecular Dynamics at the Glass Transition One Dimensional and Two Dimensional Nuclear Magnetic Resonance Studies of a Glass-Forming Discotic Liquid Crystal, J. Chem. Phys. 97 3749-3759 (1992). 

Generally, the most powerful method for stmctural elucidation of steroids is nuclear magnetic resonance (nmr) spectroscopy. There are several classical reviews on the one-dimensional (1-D) proton H-nmr spectroscopy of steroids (267). C-nmr, a technique used to observe individual carbons, is used for stmcture elucidation of steroids. In addition, C-nmr is used for biosynthesis experiments with C-enriched precursors (268). The availability of higher magnetic field instmments coupled with the arrival of 1-D and two-dimensional (2-D) techniques such as DEPT, COSY, NOESY, 2-D J-resolved, HOHAHA, etc, have provided powerful new tools for the stmctural elucidation of complex natural products including steroids (269). 

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