@article{WOS:000458618500025,
  abstract = {The 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 thermal analysis (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 orthorhombic Pccn 
 space group with a half-molecule in the asymmetric unit. Hirshfeld 
 surface analysis revealed that weak intermolecular contacts played an 
 important role in the stabilization of DBZ packing. DBZ was also 
 characterized through its mid-infrared and Raman spectra and its 
 vibrational bands were assigned based on DFT calculations with the 
 hybrid B3LYP functional, coupled with the 6-311++g (d,p) basis set. The 
 TG-DTA and HSM results shed light on the behaviour upon heating of DBZ, 
 revealing that this impurity is an unsolvated solid with high 
 thermal-oxidative stability, which sublimed, melted locally and 
 decomposed above 320 degrees C. The obtained results demonstrated that 
 slow crystallization of OXC from solvents such as ethanol and 
 dimethylsulfoxide, at 20-25 degrees C, in the presence or absence of 
 ambient light afforded DBZ. The X-ray pattern based on the SCXRD data 
 for DBZ is presented as reliable reference for its identification. (C) 
 2019 Published by Elsevier B.V.},
  added-at = {2022-05-23T20:00:14.000+0200},
  address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS},
  author = {Faudone, Sonia N and Paschoal, Alexandre R and Jr, Paulo S Carvalho and Ellena, Javier and Martins, Felipe Terra and Cuffini, Silvia L and Ayala, Alejandro P and Sperandeo, Norma R},
  biburl = {https://www.bibsonomy.org/bibtex/2e87222056a170473e6403441cafd9de2/ppgfis_ufc_br},
  doi = {10.1016/j.molstruc.2019.01.032},
  interhash = {4e0207c60ec723627874121384d3c412},
  intrahash = {e87222056a170473e6403441cafd9de2},
  issn = {0022-2860},
  journal = {JOURNAL OF MOLECULAR STRUCTURE},
  keywords = {11-dione; 19579-83-0; 5H-dibenz{[}b, FT-IR FT-Raman; Hot Powder TG-DTA}, X-ray and diffraction; f]lazepine-10 microscopy; stage {CAS},
  pages = {204-212},
  publisher = {ELSEVIER SCIENCE BV},
  pubstate = {published},
  timestamp = {2022-05-23T20:00:14.000+0200},
  title = {X-ray diffraction, vibrational and thermal study of dibenzazepinodione, 
 a pharmacopeial impurity of oxcarbazepine},
  tppubtype = {article},
  volume = 1182,
  year = 2019
}