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Updated: Feb 27, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
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Cocaine Hydrochloride Structure in Solution Revealed by Three Chiroptical Methods.
Patrik Fagan1, Lucie Kocourková1, Michal Tatarkovič1
1Departments of Analytical Chemistry and Chemistry of Natural Compounds and Forensic Laboratory of Biologically Active Substances, University of Chemistry and Technology, Technická 5, 16628, Prague, Czech Republic.
Summary
The study reveals cocaine hydrochloride
Area of Science:
- Molecular Spectroscopy
- Computational Chemistry
- Pharmacology
Background:
- Natural compound structure dictates biological activity.
- Understanding cocaine's molecular conformation is crucial for pharmacology.
- Chiroptical spectroscopy offers insights into molecular structure.
Purpose of the Study:
- To investigate the solution-phase structure of cocaine hydrochloride.
- To compare cocaine's solution conformation with its crystal structure.
- To evaluate the utility of chiroptical techniques for conformational analysis.
Main Methods:
- Measurement of electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and Raman optical activity (ROA) spectra.
- Density functional theory (DFT) calculations for spectral analysis.
- Experiments in aqueous and deuterated environments.
Main Results:
- The prevalent conformation of cocaine hydrochloride in solution differs from its crystal structure.
- Spectroscopic and computational analyses align with known cocaine-receptor complex structures.
- Chiroptical spectra demonstrated higher conformational sensitivity than unpolarized methods.
- Raman optical activity (ROA) provided the most detailed structural information.
Conclusions:
- Cocaine hydrochloride adopts diverse conformations in solution and in complexes.
- Chiroptical spectroscopy, particularly ROA, is highly effective for studying molecular conformations.
- Findings enhance understanding of cocaine's structure-activity relationship.
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