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Updated: May 4, 2026
Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Vibrational and structural behavior of (L)-cysteine ethyl ester hydrochloride in the solid state and in aqueous
M E Defonsi Lestard1, S B Díaz, M Puiatti
1INQUINOA-CONICET, Instituto de Química Física, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán , San Lorenzo 456, T4000CAN Tucumán, R. Argentina.
Abstract:
The aim of this work is to evaluate the vibrational and structural properties of l-cysteine ethyl ester hydrochloride (CE), and its electronic behavior mainly in relation to the action of the thiol and amine groups at different degrees of solvation. The crystal structure of CE was determined at room temperature by X-ray diffraction methods. Infrared and Raman spectra were collected to compare the behavior of different functional groups in the molecule, both in the solid phase and in aqueous solution. Its UV and circular dichroism spectra were also measured in aqueous solution. The influence of an aqueous environment on the CE spectra was simulated by means of implicit (polarizable continuum model) and explicit (molecular dynamics, solute-solvent clusters) methods. Calculations in explicit and continuous solvent are of interest to explain the behavior of bioavailable sites in this medium. The study was completed by natural bond orbital analysis to determine the presence of hyperconjugative interactions.
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