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Conformational flexibility of mephenesin
Patricia Écija1, Luca Evangelisti, Montserrat Vallejo
1Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV/EHU) , Campus de Leioa, Ap. 644, E-48080 Bilbao, Spain.
The Journal of Physical Chemistry. B
|April 24, 2014
Summary
Mephenesin
Area of Science:
- Molecular spectroscopy
- Quantum chemistry
- Computational chemistry
Background:
- Mephenesin's structure presents opportunities to study molecular flexibility and substituent effects.
- Understanding its conformational landscape is crucial for its biological activity.
Purpose of the Study:
- To investigate the structural and dynamical properties of mephenesin using experimental and computational methods.
- To identify and characterize the low-energy conformers of mephenesin.
Main Methods:
- Rotational spectroscopy in the 4-18 GHz range using Fourier-transform methods in supersonic expansion.
- Conformational search and ab initio/density functional quantum calculations.
- Determination of methyl torsional barriers.
Main Results:
- Three lowest-energy conformers of mephenesin were detected in the jet.
- The most stable conformer is nearly planar and stabilized by intramolecular hydrogen bonding.
- The most stable conformer is predicted to be abundant (~80%) at biologically relevant temperatures.
Conclusions:
- The study elucidates the conformational preferences and dynamics of mephenesin.
- The findings provide insights into structure-activity relationships for mephenesin and related molecules.
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