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 - http://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",
url = "http://farfar.pharmacy.bg.ac.rs/handle/123456789/418",
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.
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. Journal of Pharmaceutical and Biomedical Analysis. 2003;31(4):693-699
Popović Gordana, Sladić Dušan, Stefanović Violeta M., Pfendt Lidija, "Study on protolytic equilibria of lorazepam and oxazepam by UV and NMR spectroscopy" Journal of Pharmaceutical and Biomedical Analysis, 31, no. 4 (2003):693-699,
https://doi.org/10.1016/S0731-7085(02)00686-6 .
