Modern NMR Techniques for Synthetic Chemistry
Modern NMR Techniques for Synthetic Chemistry

Author: Julie Fisher

Publisher: CRC Press

Published: 2014-10-13

Total Pages: 364

ISBN-13: 1466592249

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A blend of theory and practical advice, Modern NMR Techniques for Synthetic Chemistry illustrates how NMR spectroscopy can be used to determine the abundance, size, shape, and function of organic molecules. It provides you with a description the NMR technique used (more pictorial than mathematical), indicating the most common pulse sequences, some practical information as appropriate, followed by illustrative examples. This format is followed for each chapter so you can skip the more theoretical details if the practical aspects are what interest you. Following a discussion of basic parameters, the book describes the utility of NMR in detecting and quantifying dynamic processes, with particular emphasis on the usefulness of saturation-transfer (STD) techniques. It details pulsed–field gradient approaches to diffusion measurement, diffusion models, and approaches to ‘inorganic’ nuclei detection, important as many synthetic pathways to new organics involve heavier elements. The text concludes with coverage of applications of NMR to the analysis of complex mixtures, natural products, carbohydrates, and nucleic acids—all areas of activity for researchers working at the chemistry-life sciences interface. The book’s unique format provides some theoretical insight into the NMR technique used, indicating the most common pulse sequences. The book draws upon several NMR methods that are resurging or currently hot in the field and indicates the specific pulse sequence used by various spectrometer manufacturers for each technique. It examines the analysis of complex mixtures, a feature not found in most books on this topic.

NMR Spectroscopy in Pharmaceutical Analysis
NMR Spectroscopy in Pharmaceutical Analysis

Author: Iwona Wawer

Publisher: Elsevier

Published: 2017-07-07

Total Pages: 525

ISBN-13: 008095152X

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For almost a decade, quantitative NMR spectroscopy (qNMR) has been established as valuable tool in drug analysis. In all disciplines, i. e. drug identification, impurity profiling and assay, qNMR can be utilized. Separation techniques such as high performance liquid chromatography, gas chromatography, super fluid chromatography and capillary electrophoresis techniques, govern the purity evaluation of drugs. However, these techniques are not always able to solve the analytical problems often resulting in insufficient methods. Nevertheless such methods find their way into international pharmacopoeias. Thus, the aim of the book is to describe the possibilities of qNMR in pharmaceutical analysis. Beside the introduction to the physical fundamentals and techniques the principles of the application in drug analysis are described: quality evaluation of drugs, polymer characterization, natural products and corresponding reference compounds, metabolism, and solid phase NMR spectroscopy for the characterization drug substances, e.g. the water content, polymorphism, and drug formulations, e.g. tablets, powders. This part is accompanied by more special chapters dealing with representative examples. They give more detailed information by means of concrete examples. Combines theory, techniques, and concrete applications—all of which closely resemble the laboratory experience Considers international pharmacopoeias, addressing the concern for licensing Features the work of academics and researchers, appealing to a broad readership

NMR-based Metabolomics
NMR-based Metabolomics

Author: Hector C Keun

Publisher: Royal Society of Chemistry

Published: 2018-01-17

Total Pages: 384

ISBN-13: 184973643X

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This book describes the state of the art in the application of NMR spectroscopy to metabolomics and will be a key title for researchers and practitioners.

Gas Phase NMR
Gas Phase NMR

Author: Karol Jackowski

Publisher: Royal Society of Chemistry

Published: 2016-02-09

Total Pages: 419

ISBN-13: 1782623817

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This book covers the recent NMR studies with the application of gaseous molecules. Among the comprehensively discussed aspects of the area it includes in particular: new multinuclear experiments that deliver spectral parameters of isolated molecules and provide the most accurate values of nuclear magnetic shielding, isotropic spin–spin coupling and relaxation times; advanced, precise and correct theoretical descriptions of spectral parameters of molecules as well as the application of gas-phase NMR measurements to chemical analysis and medicine. The progress of research in these fields is enormous and has rapidly changed our knowledge and understanding of molecular parameters in NMR spectroscopy. For example, accurate studies of the shielding for isolated molecules allow the exact determination of nuclear magnetic dipole moments, the calculated values of spectral parameters can be verified by precise gas-phase NMR measurements, and the application of hyperpolarized noble gases provides excellent MRI pictures of lungs. Aimed at graduates and researchers in spectroscopy, analytical chemistry and those researching the applications of NMR in medicine, this book presents the connections between sophisticated experiments, the theory of magnetic parameters and the exploration of new methods in practice.

NMR Spectroscopy in Drug Development and Analysis
NMR Spectroscopy in Drug Development and Analysis

Author: Ulrike Holzgrabe

Publisher: John Wiley & Sons

Published: 2008-07-11

Total Pages: 312

ISBN-13: 352761365X

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Since the development of the NMR spectrometer in the 1950s, NMR spectra have been widely used for the elucidation of the 2D structure of newly synthesized and natural compounds. In the 1980s, the high-resolution NMR spectrometer (> 300 Mhz) and 2D experiments were introduced, which opens up the possibility to determine the 3D structure of large molecules, especially biomolecules. However, NMR spectroscopy has been rarely applied to drug analysis. This book illustrates the power and versatility of NMR spectroscopy in the determination of impurities in and the content of drugs, the composition of polymer excipients, the characterization of isomeric drug mixtures, the complexity of drugs with small-size components or ions, and the behavior of drugs in acid and basic solution. In addition, NMR spectroscopy and especially the hyphenated technique with HPLC is shown to be a powerful tool to measure a drug and its metabolites in various body fluids. The solid state NMR technique can give information on the structure, especially the conformation of drugs and excipients in drug formulations. Recently, SAR by NMR, introduced by Fesik, impressively demonstrated the potential of NMR spectroscopy in drug development and in the characterization of the interaction between large molecules and ligands. The complexation between proteins, lipids and cyclodextrins with drugs is described. Finally, NMR imaging (MRI and MRS) can be used to characterize the liberation of drugs from a drug formulation. Furthermore, the distribution of substances in plants, in animals, in tissues and in humans can be visualized by imaging. In short, this book covers all aspects of drug analysis.

Ultra-High Resolution NMR Methods and Its Applications
Ultra-High Resolution NMR Methods and Its Applications

Author: Upendra Singh

Publisher:

Published: 2023-01-15

Total Pages: 0

ISBN-13: 9781992901414

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Ultra-high resolution nuclear magnetic resonance (NMR) methods refer to advanced techniques used to obtain detailed structural information about molecules. These methods use high-field magnets and specialized pulse sequences to achieve very high resolution in the NMR spectrum, allowing for the detection of very small chemical shifts and coupling constants. One of the main applications of ultra-high resolution NMR methods is in the study of biological macromolecules, such as proteins and nucleic acids. These methods can be used to determine the three-dimensional structure of these molecules, which is important for understanding their function and for drug design. Ultra-high resolution NMR methods can also be used for the study of small molecules. These methods can be used to determine the conformation of a molecule in solution, which is important for understanding the properties of a molecule and for designing new materials. In addition, ultra-high resolution NMR can be used for quantitative analysis of complex mixture. The high resolution of the spectrum allows for the detection of very small amounts of impurities or contaminants, and can also be used to determine the concentration of a component in a mixture. Overall, ultra-high resolution NMR methods are powerful tools that can provide detailed structural information about molecules and can be used in a wide range of applications, including biology, chemistry, and materials science. Nuclear magnetic resonance (NMR) spectroscopy is a potent analytical tool to comprehend physical and chemical nature (mobility, dynamics and kinetics) of small to medium size molecules for an extensive range of samples under variety of conditions such as temperature, concentration, and pH. A wealth of information related to molecular properties and interactions can be furnished by using NMR which could consequently provide utility in molecular structural identification. However, low sensitivity along with low resolution is a concern in application of NMR. Within the past few decades, NMR sensitivity has improved significantly through advancement in instrumentation as well as methodological developments. Recent upgrade in NMR instrumentation such as cryogenically cooled probes[1] has led to increase sensitivity and three to four-times better signal /noise ratio in comparison to room temperature probes leading to faster acquisition times and improved sensitivity. Resolution of spectrum is additionally improved in a high magnetic field which disperses the chemical shifts over the broad frequency range (in Hz). Nevertheless, signal overlaps continue being a limiting factor for characterizing complicated spectra. Therefore, a steady development of new pulse sequences and enhancements of the existing ones are of vital importance in improving the overall performance of NMR spectroscopy.