RESUMEN
In this article the crystal structures of the starting material TZ-5 and the key intermediate TZ-6 of temozolomide (TZ-7), an anticancer therapeutic agent, are presented, together with their spectroscopic and thermal characteristics. Both compounds crystallize in the triclinic P-1 space group. X-ray crystallography studies proved that the compound TZ-6 exists as a monohydrate. A complete structural assignment was obtained for the signals in the 1H-, 13C- and 15N-nuclear magnetic resonance spectra and the structures were confirmed by Fourier-Transform infrared and Raman spectroscopy. The article describes the importance of the high purity of TZ-6 during the small-scale plant production of TZ-7 in a desired polymorphic form III with the purity higher than 99.50%, according to an HPLC method.
Asunto(s)
Dacarbazina/análogos & derivados , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/normas , Cristalografía por Rayos X , Dacarbazina/química , Dacarbazina/normas , Modelos Moleculares , Conformación Molecular , Resonancia Magnética Nuclear Biomolecular , Espectrometría Raman , Temozolomida , TermodinámicaRESUMEN
The consistently observed inverse relationship of allergic conditions with glioma risk and our previous demonstration that immunoglobulin E (IgE) levels also were lower in glioma patients than controls suggest that atopic allergy may be related to a mechanism that inhibits or prevents glioma. We sought to extend these results with a new and larger series of patients (n = 535 with questionnaire data; 393 with IgE measures) and controls (n = 532 with questionnaire data; 470 with IgE measures). As expected, glioma cases were less likely than controls to report history of allergies [among self-reported cases, Odds ratios (OR) = 0.59, 95% confidence interval (CI): 0.41-0.85]. IgE levels also were lower in glioma cases versus controls (OR per unit log IgE = 0.89, 95% CI (0.82-0.98). However, this inverse relationship was only apparent among cases receiving temozolomide, a treatment which became part of the "standard of care" for glioblastoma patients during the study period. Among patients receiving temozolomide, IgE levels in cases whose blood samples were obtained within 30 days of diagnosis were slightly higher than controls, whereas IgE levels in cases whose blood sample was obtained >60 days after diagnosis were significantly lower than controls (OR = 0.80; 95% CI: 0.71-0.89). Thus, although our results robustly confirm the inverse association between allergy and glioma, the results for IgE are affected by temozolomide treatments which may have influenced IgE levels. These results have implications for the study of immunologic factors in glioma as well as for immunotherapy protocols for treating glioma.