Computational Pharmaceutical Solid State Chemistry
authors L. Mafra, S. M. Santos, M. Sardo, F. Heather
editors Yuriy A. Abramov
chapter title 12. Calculation of NMR Tensors
nationality International
author keywords active pharmaceutical ingredients; chemical shift tensors; nucleus-independent chemical shifts; small-molecule pharmaceuticals; solid-state nuclear magnetic resonance; X-ray diffraction
abstract This chapter focuses on the use of solid-state nuclear magnetic resonance (SSNMR) for studying small pharmaceutical molecules in synergy with theoretical calculations of NMR parameters. It emphasizes computer modeling of chemical shift tensors (CSTs) to overcome the difficulty in using experimental chemical shifts (CSs) alone to determine specific structural features. The chapter provides a brief review of the most relevant computational methods employed to calculate NMR chemical shieldings, and reports a number of case studies where computer modeling is used in tandem with SSNMR spectroscopy and X-ray diffraction (XRD) to provide structure details in solid active pharmaceutical ingredients (APIs). It focuses on correlating calculated NMR parameters with relevant structure features. The applications of nucleus-independent chemical shifts (NICS) values and maps are quite diverse, and are predominantly used in the characterization of molecular aromaticity and the quantification of induced ring currents, sometimes focusing on their topological particularities.
publisher John Wiley & Sons, Inc
isbn 978-1-118-70074-7
year published 2016
beginning page 287
ending page 329