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Neutron Crystallography Data Collection and Processing for Modelling Hydrogen Atoms in Protein Structures
Published on: December 1, 2020
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Naloxegol hydrogen oxalate displaying a hydrogen-bonded layer structure
Thomas Gelbrich1, Christoph Langes1, Marijan Stefinovic2
1University of Innsbruck, Institute of Pharmacy, Innrain 52, 6020 Innsbruck, Austria.
Summary
This study details the crystal structure of naloxegol hydrogen oxalate. The naloxegol cation
Area of Science:
- Crystallography
- Supramolecular Chemistry
- Medicinal Chemistry
Background:
- Naloxegol is a peripherally acting mu-opioid receptor antagonist.
- Understanding the solid-state structure of naloxegol is crucial for drug formulation and development.
Purpose of the Study:
- To elucidate the crystal structure of naloxegol hydrogen oxalate.
- To characterize the hydrogen bonding interactions and network topology in the crystal.
Main Methods:
- Single-crystal X-ray diffraction analysis.
- Structural analysis of hydrogen bonding and network formation.
Main Results:
- The naloxegol cation adopts a 'squashed O' conformation due to its polyether chain.
- Hydrogen oxalate anions form infinite chains through O-H⋯O hydrogen bonds.
- A 2D hydrogen-bonded network is formed by interactions between naloxegol and hydrogen oxalate ions.
- The network exhibits a 3,5-connected topology with the 3,5 L50 net.
Conclusions:
- The crystal structure reveals specific conformational preferences of the naloxegol cation.
- The intricate hydrogen bonding network dictates the supramolecular architecture.
- The identified 3,5 L50 topology provides insights into crystal packing and potential solid-state properties.
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