Análise térmica de esparfloxacino

Abstract

Foi realizada a análise térmica de esparfloxacino,fluorquinolona de terceira geração que possui potenteatividade contra bactérias Gram-positivas, como Streptococcus pneumoniae e Staphylococcus aureus inclusive cepas meticilina resistentes (MRSA), bactériasGram-negativas, anaeróbios, Legionella spp., Mycoplasma spp., Chlamydia spp. e Mycobacterium spp. Nas curvas DTA observa-se pico endotérmico de fusãona temperatura de 276,5 °C. A curva DTA, em ar sintético,apresenta dois picos exotérmicos (341,6 e 579,2 °C), atribuídos à decomposição do composto. A curva TG permite observar a perda de massa total em duas etapas,entre as temperaturas 285,5 e 645,3 °C. A curva DTA,em atmosfera de nitrogênio, apresenta pico exotérmicode decomposição na temperatura de 340,0 oC e na curva TG, a perda de massa inicia-se na temperatura de 254,4 °C.

Sparfloxacin, a third-generation fluoroquinolone, is a potent antibacterial agent against a wide range of Grampositive and Gram-negative organisms, for example Streptococcus pneumoniae, Staphylococcus aureus (including methicillin-resistant strains), Legionella spp., Mycoplasma spp., Chlamydia spp. and Mycobacterium spp. This compound has been submitted to thermal analysis and the results are presented here. The DSC curve of sparfloxacin has an endothermic peak that indicates a melting point at 276.5 °C. The DTA curve of the sample in synthetic air shows two exothermic peaks, at 341.6 and 579.2 °C, attributed to compound decomposition. In the TG curve, the loss of mass can be seen to occur in two steps between 285.5 and 645.3 °C. The DTA curve obtained in a nitrogen atmosphere shows an exothermic peak, with decomposition of sparfloxacin at 340.0 °C; from the corresponding TG plot, the loss of mass starts at 254.4 °C.