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Updated: Sep 28, 2025

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Resolving alternative structure determinations of indapamide using 13C solid-state NMR
Caitlin L Evans1, Ivana Radosavlijević Evans1, Paul Hodgkinson1
1Department of Chemistry, Durham University, Stockton Road, Durham, DH1 3LE, UK. paul.hodgkinson@durham.ac.uk.
Abstract:
The conflict between alternative crystal structures in the Cambridge Structural Database for the diuretic drug indapamide hemihydrate (IND) has been resolved with the aid of 13C solid-state NMR. IND is seen to contain multiple distinct molecules in the asymmetric unit (Z' = 4) rather than exhibiting disorder in the orientation of sulfonamide groups. The NMR crystallographic approach is a more effective tool for distinguishing between alternative structures than naïve judgements of quality based on crystallographic refinement agreement factors.
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