Síntese e atividade antimicrobiana de 3-trifluormetil(oxo)-pirimido[1,2-a]benzimidazóis

Abstract

This work presents the synthesis of a series of 3-trifluormethyl(oxo)-pyrimido[1,2-a]benzimidazoles from the cyclocondensation reaction between 2-amino-1H-benzimidazol and 4-alcoxy-1,1,1-trihalo-3-alquen-2-ones. The obtaintion of the 3-trifluormethyl-pyrimido[1,2-a]benzimidazoles were regioespecific and the yields were, in general, very good. On the other hand, the synthesis of 3-oxo-pyrimido[1,2-a]benzimidazoles were not always regioespecific. In such cases, two regiosiomers could be identified by NMR. From these reactions, three tetrahydropyrimidines were also isolated and identified. The derivatization of some 3-oxo-pyrimido[1,2-a]benzimidazoles were achieved by alkylation of N-4, or even, by the bromination of position 2 in the 3,4-dihydro-3-oxo-pyrimido[1,2-a]benzimidazol. Finaly, this study shows the evaluation of the antimicrobiane activity of compunds through bioautography essays.