Thermal and spectroscopic characterization, antioxidant evaluation and pyrolysis of losartan with some bivalent metals

• Pyrolysis of losartan with Mn, Fe, Co, Ni, Cu and Zn has not been published.
• Pyrolysis conditions indicates that all metals have the same interaction with the Los.
• KCl was formed during thermal decomposition of Los.
• Antioxidants activity have been reported to have interesting to pharmacological applications.
• The compound Mn(Los)2·4H2O exhibited the highest antioxidant activity of all compounds.

Solid state M-Los compounds, where M stands for bivalent Mn, Fe, Co, Ni, Cu or Zn and Los is losartan. The materials were characterized by Fourier transform infrared spectroscopy (FTIR), simultaneous termogravimetry–differential scanning calorimetry (TG–DSC), simultaneous termogravimetry–differential scanning calorimetry coupled with Fourier transform infrared spectroscopy (TG/DSC–FTIR) and evaluating antioxidant activity with DPPH. The results can be to inform the thermal behaviour, hydration, stoichiometric relationship, metal-ligand interaction, antioxidant capacity and released gases during of the thermal decomposition of compounds. The thermal behavior of the compound showed similar thermal behavior in air atmosphere and nitrogen atmosphere. The gaseous products released under dry air and nitrogen atmospheres were CO, CO2, NH3, CH3NH2, NO and H2O, CO, NH3, CH3NH2, HCN, respectively. The DPPH test indicated that the scavenging free radicals from MnLos2·4H2O and HLos were c.a. 20% higher than the others compounds. These results indicate MnLos2.4H2O to others investigations as toxicological and pharmacological.