Application of High-Resolution NMR

The advent of a commercial 220 MHz NMR instrument has permitted the application of high resolution NMR to many larger molecules and the B 12-system is no exception. This technique has allowed more detailed assignments to be made thus permitting the study of more subtle chemical effects such as changes in molecular conformation. 

The structure determination of organic molecules in solution—constitution, configuration, and conformation—is probably the most important application of high-resolution NMR spectroscopy. Among all existing... 

H. Egge Structural analysis of blood group ABH, I, i, Lewis and related glyco-sphingolipids. Application of high resolution NMR and FAB mass spectrometry... 

Netropsin complexes with nucleic acids have been monitored by spectroscopic techniques at the oligomer duplex and DNA level (89-96). Our research focussed on the application of high resolution NMR spectroscopy to elucidate structural and dynamic aspects of netropsin complexes with the self-complementary octanucleotide dG-dG-dA-dA-dT-dT-dC-dC duplex (9 7) and the synthetic DNA poly(dA-dT) (27) in aqueous solution. 

Valuable reviews and books of structural analysis of elastomers have been published by several authors [1-6]. Some of these reviews provide excellent explanation on the basic theory of sequence distribution of copolymer and NMR techniques applicable to elastomers. Typical high-resolution 3H- and 13C-NMR spectra of various vulcanisates and raw rubbers are depicted in a book written by Kelm [6]. The assignments and references shown for each rubber are very useful for structural studies of elastomers. In view of recent progress in the hardware and software of NMR, this chapter describes some of the more recent applications of high-resolution NMR to the structural characterisation of elastomers, after a brief description on the fundamental structural features of elastomers. 

In the following section, certain topics are selected to introduce the recent applications of high-resolution NMR to the structural characterisation of elastomers, together with basic information on signal assignments. 

The structure determination of organic molecules in solution — constitution, configuration and conformation — is probably the most important application of high-resolution NMR spectroscopy. Sophisticated methods based on classical NMR parameters like chemical shifts, /-couplings and nuclear Overhauser enhancement (NOE) have been developed for deriving structural models.1 2 The approach has been successfully applied to a vast number of molecules including thousands of biomacromolecules and uncountable natural and synthetic products. 

Most books concerned with application of high resolution NMR include discussion of many experimental aspects. Recording One-Dimensional High Resolution Spectra40 in the Encyclopedia of NMR also provides a good overview. 150 and More... 

Few cases have been reported of the application of high-resolution NMR spectroscopy to the study of clinical toxicological problems. However, the reports discussed above were so successful that it seems certain that H NMR... 

The application of high resolution NMR spectroscopy made the quantitative measurement of sequence distribution feasible and allowed one to compare actual polymer chains with theoretical predictions. A simple illustration is given here considering only triad sequences. 

High-resolution applications of NMR in food science have been reviewed.26 Since the appearance of this review in 1984, the use of 2D NMR techniques has become commonplace, greatly increasing the power of NMR as a method for structural analysis of complex natural products, including many minor food components. In this section, however, attention will be given to quantitative rather than structural applications of high-resolution NMR. 

Application of High-Resolution NMR Spectroscopy to Polymer Chemistry... 

Eable 1.1. A summary of some key developments that have had a major influence on the practice and application of high-resolution NMR spectroscopy in chemical research... 

The stereospecific polymerization of ot-olefins is one of the best examples which illustrate the possible applications of high resolution NMR to the determination of reaction mechanisms. As a matter of fact, the stereoregular structure of the reaction products and the sensitivity of chemical shifts to stereochemical environments make it possible to obtain considerable and important information about very subtle details of the reaction mechanism. This is especially true when NMR is used in conjunction with isotopic substitution. 

Schiller, J. and Arnold, K., Application of high resolution NMR spectroscopy to the characterization of the phospholipid composition of tissues and body fluids -a methodological review, Med Sci Monit, 8 (2002) MT205-222. 

Another recent application of high resolution NMR was to study the reaction mechanism of the solvolysis of norbornen-2-yl derivatives (7) The acetolysis of the mono-deuterium compound 1, [2-d] exo-5-norbornen-2-yl brosylate, for instance led to the products to 5. The deuterium label distribution of these products was determined unambiguously (Figure 6) and thus allowed the elimination of a previously proposed mechanism which required the intervention of asymmetrical homoallyllc cation intermediates. 

Hung Yu Chen, Application of high resolution NMR spectroscopy to elastomers in solution. Rubber Chem. Technol. 41, 47 (1968) (also contains data on thermoplasts, etc.). 

The applications of high-resolution NMR to polymers are many and varied, reflecting the wide range of chain structural features accessible by NMR. Many applications are no diflferent from the ubiquitous use of NMR as a qualitative analytical tool in organic structural analysis, but others exploit the capability of NMR in providing information about aspects of molecular architecture that are peculiar to polymers and can be investigated by no other technique. Here the principal types of information are summarised in approximate order of sophistication. 

The design of powerful NMR spectrometers and high-capacity computers as well as the development of advanced techniques stimulated the application of high-resolution NMR spectroscopy in the field of conformational analyses of peptides H-NMR spectroscopy, which this survey will be restricted to, is the mo widely applied method but and are nudd of growing interest... 

Applications of high-resolution NMR spectroscopy in metabolic characterization of human cancer over the last two decades have been reviewed by Sitter et al These applications rely on the ability of NMR of biological tissues to reflect tissue metabolites in vivo and in vitro). Thus, aberrant biochemical reactions can be observed by NMR, which is used to analyze cancer tissue for diagnostic and prognostic markers. For tissue specimens, studies have shown that ex vivo NMR can metabolically characterize... 

This monograph deals with recent advances in this area and provides complete information on the principles, theory, and applications of high resolution NMR in solids. The necessary theoretic background is supplied and many examples and problems are thoroughly treated. To this second revised edition (the first edition was published in the series NMR-Basic Principles and Progress ) have been added chapters on two-dimensional spectroscopy, multi-quantum spectroscopy, and relacation theory. 

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