Study of a conformational equilibrium of lisinopril by HPLC, NMR, and DFT.
The isomerization of lisinopril has been investigated using chromatographic, NMR spectroscopic, and theoretical calculations. The NMR data, particularly the NOEDIFF experiments, show that the major species that was eluted first is the trans form. The proportion was 77% and 23% for the trans and cis, respectively. The thermodynamic parameters (ΔH, ΔS, and ΔG) were determined by varying the temperature in the NMR experiments. The interpretations of the experimental data were further supported by DFT/B3LYP calculations.
Laboratoire de Chimie Analytique Appliquée, Faculté des Sciences de Bizerte, 7021 Zarzouna, Tunisia.
Sondes
S
Bouabdallah
Laboratoire de Chimie Organique Structurale, Synthèse et Etude Physico-Chimique (Equipe de Chimie de Coordination), Faculté des Sciences de Tunis, 1060 Tunis, Tunisia.
Med Thaieb
MT
Ben Dhia
Laboratoire de Chimie Analytique Appliquée, Faculté des Sciences de Bizerte, 7021 Zarzouna, Tunisia.
Med Rida
MR
Driss