Evidence of polymorphism on the Antytripanosomal Naphthoquinone (4E)-2-(1H-Pyrazol-3-ylamino)-4-(1H-pyrazol-3-ylimino)naphthalen-1(4H)-one.

Scientia Pharmaceutica

Wolfgang Kubelka

Año: 2013 vol. 81 p. 855 - 855

2218-0532

he aim of this study was to characterize the solid state properties of 2-N-[3(5)-pyrazolylamino]-1,4-naphthoquinone-4-imine (BiPNQ), a compound with significant inhibitory activity against Trypanosoma cruzi, the ethiological agent of Chagas´ disease (American trypanosomiasis). Methods used included Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Fourier Transform Infrared Spectroscopy (FTIR), Powder X-Ray Diffraction (PXRD) and Hot Stage and Confocal Microscopy. Two BiPNQ samples were obtained by crystallization from absolute methanol and 2-propanol-water that exhibited different thermal behaviours, PXRD patterns and FTIR spectra, indicating the existence of an anhydrous form (BiPNQ-I) and a solvate (BIPNQ-s), which on heating desolvated leading to the anhydrous modification BiPNQ-I. It was determined that FTIR, DSC, and PXRD are useful techniques for the characterization and identification of the crystalline modifications of BiPNQ.