Synthesis, characterization, and in vitro antimicrobial evaluation of new 5-chloro-8-bromo-3-aryl-1,2,4-triazolo[4,3-c]pyrimidines

A series of new 5-chloro-8-bromo-3-aryl-1,2,4-triazolo[4,3-c]pyrimidines (4a-j) have been accomplished in excellent yields by the oxidative cyclization of pyrimidinylhydrazines (3a-j) of various aryl aldehydes with one equivalents of iodobenzene diacetate in methanol. The chemical structures of the synthesized compounds were confirmed by elemental analyses, FT-IR, H-1 NMR, C-13 NMR, and mass spectral studies. Ten new compounds (4a-j) were tested in vitro for their antimicrobial activity against clinically isolated strains. Variable and modest activities were observed against the investigated strains of bacteria and fungi. Compounds 4f, 4i, and 4j demonstrated good antimicrobial activity against all the tested microbial strains.