Fluorinated 1,2,4-Triazolo[1,5-a]pyrimidine-6-carboxylic acid derivatives as antimycobacterial agents.

A series of fluorinated 1,2,4-triazolo[1,5-a]pyrimidine-6-carboxylic acid derivatives was designed and synthesized as fluoroquinolone analogues. The synthesized compounds were screened against Mycobacterium tuberculosis H(37)R(v) strain at 6.25 microg/mL concentration. Compound 4, the 7-oxo-2-(trifluoromethyl)-4,7-dihydro-1,2,4-triazolo[5,1-a]pyrimidine-6-carboxylic acid was found to be a very potent inhibitor, being able to inhibit 92% growth of M. tuberculosis H(37)R(v )at 6.25 microg/mL concentration. At the same time, it proofed to be nontoxic to mammalian cells (IC(50) > 62.5 microg/mL in VERO cells).