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Investigating albendazole desmotropes by solid-state NMR spectroscopy
Ana K Chattah1, Rongchun Zhang, Kamal H Mroue
1Facultad de Matemática, Astronomía y Física and IFEG (CONICET), Universidad Nacional de Córdoba , Ciudad Universitaria, X5000HUA Córdoba, Argentina.
Molecular Pharmaceutics
|January 14, 2015
Summary
Investigating Albendazole forms I and II revealed distinct tautomers and dimeric structures. Solid-state NMR and other techniques characterized these forms, impacting drug bioavailability.
Area of Science:
- Solid-state chemistry
- Pharmaceutical sciences
- Molecular spectroscopy
Background:
- Physicochemical properties of pharmaceutical compounds are crucial for drug product development.
- Understanding solid forms, like desmotropy, impacts solubility and bioavailability.
- Albendazole is an important pharmaceutical compound with known solid forms.
Purpose of the Study:
- To characterize the molecular structure and solid-state properties of Albendazole forms I and II.
- To investigate the desmotropy of Albendazole at the atomic level.
- To identify tautomers and hydrogen bonding interactions in Albendazole solid forms.
Main Methods:
- Ultrafast magic angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy.
- Powder X-ray diffraction, thermal analysis, and Fourier transform infrared spectroscopy.
- High-resolution 1D and 2D NMR experiments for chemical shift correlation.
Main Results:
- Distinguished Albendazole forms I and II using multiple analytical techniques.
- Deciphered intramolecular and intermolecular hydrogen bonding interactions.
- Unequivocally identified tautomers and characterized dimeric structures in both forms.
Conclusions:
- Solid-state NMR is effective for characterizing pharmaceutical desmotropy.
- Albendazole forms I and II exhibit distinct dimeric structures linked by specific hydrogen bonds.
- Understanding these solid-state properties is vital for optimizing Albendazole drug products.
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