5-Nitro-2,6-dioxohexahydro-4-pyrimidinecarboxamides: synthesis, in vitro antimycobacterial activity, cytotoxicity, and isocitrate lyase inhibition studies.

Fourteen 5-nitro-2,6-dioxohexahydro-4-pyrimidinecarboxamides (3a-n) were synthesized and evaluated for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB), multidrug-resistant Mycobacterium tuberculosis (MDR-TB), and Mycobacterium smegmatis (MC(2)), as well as their cytotoxicity and MTB isocitrate lyase (ICL) inhibition activity. 1-Cyclopropyl-6-fluoro-8-methoxy-7-(3-methyl)-4-[(5-nitro-2,6-dioxohexahydro-4-pyrimidinyl)carbonyl]piperazino-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid (3n) was found to be the most active compound in vitro with MICs of < 0.17 and 0.17 µM against log-phase MTB and MDR-TB, respectively. Some compounds showed 20-45% inhibition against MTB ICL at 10 µM.