Book Review pubs.acs.org/jnp
Review of The Assignment of the Absolute Configuration by NMR Using Chiral Derivatizing Agents: A Practical Guide to establish the absolute configuration of polyfunctional compounds, emphasizing the practical aspects of the assignment. In the final chapter of this book (Chapter 6), the authors provide 50 exercises that could be used as training for the application of this methodology. An aspect that we really appreciated was the use of figures at the beginning of each section that summarize the structure of compounds that could be assigned, the most appropriate CDAs for each kind of molecule, and how to interpret the results obtained. In fact, nearly every page of every chapter has at least one figure, which may be beneficial to those that favor a visual explanation of the process and data interpretation. The Assignment of the Absolute Conf iguration by NMR Using Chiral Derivatizing Agents: A Practical Guide offers a thorough overview of an otherwise difficult-to-cover topic in natural products chemistry. However, the information provided in this guide can also be found in two different reviews published by the authors (Chem. Rev. 2004, 104, 17−117, and Chem. Rev. 2012, 112, 4603−4641). Altogether these three contributions will serve as a reference source in the field when NMR-based methods are used for the assignment of absolute configuration. Finally, as all the examples shown are explained in detail and all figures and spectra shown can be obtained in color from the publisher, the book could also be utilized for teaching purposes. We recommend the addition of this guide to the book (and/or ebook) collection of any natural products group interested in structure elucidation.
The Assignment of the Absolute Configuration by NMR Using Chiral Derivatizing Agents: A Practical Guide. By José M. Seco, Emilio Quiñoá, and Ricardo Riguera (University of Santiago de Compostela). Oxford University Press, New York, NY, 2015. 244 pp. $79.95. ISBN 978-0-19-999680-3.
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tructure elucidation is likely one of the more difficult tasks in natural products research. In particular, assigning the absolute configuration is a challenge for all levels (students or professionals). However, knowledge of the absolute configuration of a compound is critical, since chirality determines important physicochemical, biological, and pharmacological properties. Several techniques have been used to generate information about the configuration of organic compounds, and some examples include X-ray diffraction and chiroptical methods, such as optical rotatory dispersion (ORD) or optical rotation (OR). Other methods include electronic and vibrational circular dichroism (ECD and VCD), Raman optical activity (ROA), and nuclear magnetic resonance (NMR)-based techniques. The latter has demonstrated to be a powerful and reliable protocol when the amount of sample is limited, monocrystals are unavailable, or samples do not have a UVactive chromophore. Thus, these methods have become essential tools in natural products research. The Assignment of the Absolute Configuration by NMR Using Chiral Derivatizing Agents: A Practical Guide shows the fundamentals of NMRbased techniques for determining the absolute configuration of organic compounds, along with the main characteristics of eight arylalkoxyacetic acids used as chiral derivatizing agents, providing a clear explanation about their conformational preference, compounds whose absolute configuration could be assigned, and the scope and limitations of this methodology. In general, the book is oriented to organic and natural products chemists who already have knowledge about NMR and structure elucidation. The authors present 54 examples from their own research for determining the absolute configuration of mono- and polyfunctional compounds, using eight different chiral derivatizing agents (CDAs) and showing NMR spectra, experimental details, and molecular models that facilitate the interpretation and understanding of this methodology. The book is organized into six chapters. Chapter 1 shows the basics of the assignment of the absolute configuration using CDAs, as well as a summary of the recommended agents for the assignment of monofunctional and polyfunctional substrates. Chapter 2 provides information about the experimental details related to the preparation of CDAs and their derivatives and the best conditions to carry out the NMR experiments. Chapters 3 and 4 describe the application of NMR-based methods and reagents used to determine the absolute configuration of monofunctional substrates using double and single derivatization procedures and show numerous examples and spectra of the application of this methodology. Chapter 5 provides examples of the application of double and single derivatization © 2017 American Chemical Society and American Society of Pharmacognosy
Nicholas H. Oberlies José Rivera-Chávez
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The University of North Carolina at Greensboro, Greensboro, North Carolina, United States
AUTHOR INFORMATION
ORCID
Nicholas H. Oberlies: 0000-0002-0354-8464 Notes
The authors declare no competing financial interest.
Published: February 21, 2017 1231
DOI: 10.1021/acs.jnatprod.7b00122 J. Nat. Prod. 2017, 80, 1231−1231
