Síntese de derivados imidazo-pirazolo pirimidínicos para avaliação da atividade antibacteriana

Abstract

Diseases caused by bacteria have been a major problem worldwide since they are responsible for many deaths every year around the world and high health-related costs. In addition, the drug resistance has been raised significantly. Therefore, it is very relevant the research in order to developing new classes of antibacterial. There are many reports in the literature showing that heterocyclic compounds containing nitrogen atom have great biological potential, specially pyrazole moiety, which has showed remarkable antimicrobial activity. Thus, in this work aimed to synthesize new seven pyrazole derivatives 7-aryl-2,3,6,7-tetrahydro-5H-imidazo[1,2-c]pyrazolo[4,3- e]pyrimidine-5-thiones 1(a-g). The raw materials 5-amino-1-aryl-1H-pyrazole-4- carbonitriles 3(a-g) and the key intermediates 5-amino-1-aryl-4-(4,5-dihydro-1H imidazole-2-yl)-1H-pyrazoles 2(a-g) were obtained in 47 to 71 % and 24 to 88% yields, respectively. The final products 1(a-g) were synthesized in 31 to 91% yields and completely characterized by Infrared Spectroscopy (FT-IR), High Resolution Mass Sprectrometry (HRMS) and Nuclear Magnetic Resonance (NMR). The compounds 1(a-g) are being evaluted against Staphylococcus aureus and Escherichia coli through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). These derivatives 1(a-g) did not show antibacterial activity against E. coli.