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19:58
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
(R)-(+)-2-{[(3-Methyl-4-nitro-pyridin-2-yl)meth-yl]sulfin-yl}-1H-benzimidazole
Acta Crystallographica. Section E, Structure Reports Online
|November 18, 2011
Summary
The absolute R-configuration of a Dexlansoprazole intermediate was determined. Crystal structure analysis revealed molecular chains formed via hydrogen bonds, offering insights into anti-ulcer drug development.
Area of Science:
- Organic Chemistry
- Crystallography
- Medicinal Chemistry
Background:
- Dexlansoprazole is a proton pump inhibitor (PPI) used for treating acid-related gastrointestinal disorders.
- Understanding the stereochemistry and crystal structure of key intermediates is crucial for optimizing drug synthesis and efficacy.
Purpose of the Study:
- To determine the absolute configuration of a specific intermediate in Dexlansoprazole synthesis.
- To elucidate the crystal structure and intermolecular interactions of the title compound.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the absolute configuration and crystal structure.
- Analysis of hydrogen bonding networks (N-H⋯N and C-H⋯O) was performed.
Main Results:
- The absolute configuration of the title compound (C14H12N4O3S) was established as R.
- The crystal structure shows molecules forming chains along the b-axis.
- Intermolecular interactions include N-H⋯N and C-H⋯O hydrogen-bonded dimers and weaker C-H⋯O interactions.
Conclusions:
- The determined R-configuration is vital for the stereoselective synthesis of Dexlansoprazole.
- The identified hydrogen bonding patterns provide insights into the solid-state packing and stability of the intermediate.
- This structural information can aid in the development of improved anti-ulcer therapies.
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