X-Ray diffraction, vibrational and thermal study of dibenzazepinodione, a pharmacopeial impurity of oxcarbazepine

NORMA R. SPERANDEO

JOURNAL OF MOLECULAR STRUCTURE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019 vol. 1182 p. 204 - 204

0022-2860

he antiepileptic drug oxcarbazepine (OXC) was crystallized from various organic solvents, and mixtures of OXC crystals and red-orange particles were obtained. In view of the pharmaceutical relevance of OXC, this study focuses on the isolation and characterization of these red-orange crystals by structural [single crystal (SCXRD), powder X-ray diffraction (PXRD) and Hirshfeld surface analysis], vibrational [Fourier transform infrared (FT-IR), Fourier transform Raman (FT-Raman) and Density functional theory (DFT) calculations], and thermal methods of analysis [simultaneous thermogravimetry-differential thermalanalysis (TG-DTA) and hot stage microscopy (HSM)]. According to SCXRD, the red-orange crystals corresponded to a recently codified impurity of OXC, referred as dibenzazepinodione (DBZ) or impurity D in the United States and European Pharmacopoeias respectively, which crystallized in the orthorhombicPccn space group with a half-molecule in the asymmetric unit. Hirshfeld surface anal