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Application of vibrational spectroscopy supported by theoretical calculations in identification of amorphous and crystalline forms of cefuroxime axetil.

Talaczyńska A, Lewandowska K, Jelińska A, Garbacki P, Podborska A, Zalewski P, Oszczapowicz I, Sikora A, Kozak M, Cielecka-Piontek J - ScientificWorldJournal (2015)

Bottom Line: FT-IR and Raman scattering spectra of cefuroxime axetil were proposed for identification studies of its crystalline and amorphous forms.An analysis of experimental spectra was supported by quantum-chemical calculations performed with the use of B3LYP functional and 6-31G(d,p) as a basis set.The geometric structure of a cefuroxime axetil molecule, HOMO and LUMO orbitals, and molecular electrostatic potential were also determined by using DFT (density functional theory).

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland.

ABSTRACT
FT-IR and Raman scattering spectra of cefuroxime axetil were proposed for identification studies of its crystalline and amorphous forms. An analysis of experimental spectra was supported by quantum-chemical calculations performed with the use of B3LYP functional and 6-31G(d,p) as a basis set. The geometric structure of a cefuroxime axetil molecule, HOMO and LUMO orbitals, and molecular electrostatic potential were also determined by using DFT (density functional theory). The benefits of applying FT-IR and Raman scattering spectroscopy for characterization of drug subjected to degradation were discussed.

No MeSH data available.


The molecular electrostatic potential of cefuroxime axetil. The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity.
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fig6: The molecular electrostatic potential of cefuroxime axetil. The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity.

Mentions: For investigating the chemical reactivity of a molecule, the molecular electrostatic potential (MEP) surface of cefuroxime axetil was plotted over an optimized electronic structure by using a density functional B3LUP method with 6-31G(d,p) as a basis set. The MEP is especially important for identification of the reactive sites for a nucleophilic and electrophilic attack in hydrogen-bonding interactions and for understanding the process of biological recognition. The different values of the molecular electrostatic potential at the surface of cefuroxime axetil are marked with different colors. The color code of the map represents the range from −5.75 10−2 eV (deepest red) to 5.75 102 eV (deepest blue). The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity as shown in Figure 6. The maxima of the negative regions are localized on the (acetyloxy)ethyl ester substituent and the carbonyl group coupling with the 5-thia-1-azobicyclic structure, while the maximum of the positive region is localized on the (aminocarbonyl)oxy methyl group in cefuroxime axetil.


Application of vibrational spectroscopy supported by theoretical calculations in identification of amorphous and crystalline forms of cefuroxime axetil.

Talaczyńska A, Lewandowska K, Jelińska A, Garbacki P, Podborska A, Zalewski P, Oszczapowicz I, Sikora A, Kozak M, Cielecka-Piontek J - ScientificWorldJournal (2015)

The molecular electrostatic potential of cefuroxime axetil. The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4306215&req=5

fig6: The molecular electrostatic potential of cefuroxime axetil. The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity.
Mentions: For investigating the chemical reactivity of a molecule, the molecular electrostatic potential (MEP) surface of cefuroxime axetil was plotted over an optimized electronic structure by using a density functional B3LUP method with 6-31G(d,p) as a basis set. The MEP is especially important for identification of the reactive sites for a nucleophilic and electrophilic attack in hydrogen-bonding interactions and for understanding the process of biological recognition. The different values of the molecular electrostatic potential at the surface of cefuroxime axetil are marked with different colors. The color code of the map represents the range from −5.75 10−2 eV (deepest red) to 5.75 102 eV (deepest blue). The positive (blue) regions of the MEP are related to electrophilic reactivity and the negative (red) to nucleophilic reactivity as shown in Figure 6. The maxima of the negative regions are localized on the (acetyloxy)ethyl ester substituent and the carbonyl group coupling with the 5-thia-1-azobicyclic structure, while the maximum of the positive region is localized on the (aminocarbonyl)oxy methyl group in cefuroxime axetil.

Bottom Line: FT-IR and Raman scattering spectra of cefuroxime axetil were proposed for identification studies of its crystalline and amorphous forms.An analysis of experimental spectra was supported by quantum-chemical calculations performed with the use of B3LYP functional and 6-31G(d,p) as a basis set.The geometric structure of a cefuroxime axetil molecule, HOMO and LUMO orbitals, and molecular electrostatic potential were also determined by using DFT (density functional theory).

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland.

ABSTRACT
FT-IR and Raman scattering spectra of cefuroxime axetil were proposed for identification studies of its crystalline and amorphous forms. An analysis of experimental spectra was supported by quantum-chemical calculations performed with the use of B3LYP functional and 6-31G(d,p) as a basis set. The geometric structure of a cefuroxime axetil molecule, HOMO and LUMO orbitals, and molecular electrostatic potential were also determined by using DFT (density functional theory). The benefits of applying FT-IR and Raman scattering spectroscopy for characterization of drug subjected to degradation were discussed.

No MeSH data available.