Protolytic equilibria in homogeneous and heterogeneous systems of lorazepam and oxazepam, which are sparingly soluble ampholytes from the class of 1,4-benzodiazepines, were studied at 25 degreesC and ionic strength of 0.1 M. Acidity constants and equilibrium constants in a heterogeneous system were determined. On the basis of the analysis of the corresponding C-13- and H-1-NMR spectra, deprotonation site in the molecules of the investigated compounds was predicted. Finally, the correlation between chemical shifts in the H-1-NMR spectra and the acidity of the amide proton of 1,4-benzodiazepines was established.
Source:
Journal of Pharmaceutical and Biomedical Analysis, 2003, 31, 4, 693-699
TY - JOUR
AU - Popović, Gordana
AU - Sladić, Dušan
AU - Stefanović, Violeta M.
AU - Pfendt, Lidija
PY - 2003
UR - https://farfar.pharmacy.bg.ac.rs/handle/123456789/418
AB - Protolytic equilibria in homogeneous and heterogeneous systems of lorazepam and oxazepam, which are sparingly soluble ampholytes from the class of 1,4-benzodiazepines, were studied at 25 degreesC and ionic strength of 0.1 M. Acidity constants and equilibrium constants in a heterogeneous system were determined. On the basis of the analysis of the corresponding C-13- and H-1-NMR spectra, deprotonation site in the molecules of the investigated compounds was predicted. Finally, the correlation between chemical shifts in the H-1-NMR spectra and the acidity of the amide proton of 1,4-benzodiazepines was established.
PB - Pergamon-Elsevier Science Ltd, Oxford
T2 - Journal of Pharmaceutical and Biomedical Analysis
T1 - Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy
VL - 31
IS - 4
SP - 693
EP - 699
DO - 10.1016/S0731-7085(02)00686-6
ER -
@article{
author = "Popović, Gordana and Sladić, Dušan and Stefanović, Violeta M. and Pfendt, Lidija",
year = "2003",
abstract = "Protolytic equilibria in homogeneous and heterogeneous systems of lorazepam and oxazepam, which are sparingly soluble ampholytes from the class of 1,4-benzodiazepines, were studied at 25 degreesC and ionic strength of 0.1 M. Acidity constants and equilibrium constants in a heterogeneous system were determined. On the basis of the analysis of the corresponding C-13- and H-1-NMR spectra, deprotonation site in the molecules of the investigated compounds was predicted. Finally, the correlation between chemical shifts in the H-1-NMR spectra and the acidity of the amide proton of 1,4-benzodiazepines was established.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Journal of Pharmaceutical and Biomedical Analysis",
title = "Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy",
volume = "31",
number = "4",
pages = "693-699",
doi = "10.1016/S0731-7085(02)00686-6"
}
Popović, G., Sladić, D., Stefanović, V. M.,& Pfendt, L.. (2003). Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy. in Journal of Pharmaceutical and Biomedical Analysis
Pergamon-Elsevier Science Ltd, Oxford., 31(4), 693-699.
https://doi.org/10.1016/S0731-7085(02)00686-6
Popović G, Sladić D, Stefanović VM, Pfendt L. Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy. in Journal of Pharmaceutical and Biomedical Analysis. 2003;31(4):693-699.
doi:10.1016/S0731-7085(02)00686-6 .
Popović, Gordana, Sladić, Dušan, Stefanović, Violeta M., Pfendt, Lidija, "Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy" in Journal of Pharmaceutical and Biomedical Analysis, 31, no. 4 (2003):693-699,
https://doi.org/10.1016/S0731-7085(02)00686-6 . .
