RESUMO
Fifty one newer 1-(cyclopropyl/2,4-difluorophenyl/tert-butyl)-1,4-dihydro-8-methyl-6-nitro-4-oxo-7-(substituted secondary amino)quinoline-3-carboxylic acids were synthesized from 1,3-dichloro-2-methylbenzene and evaluated for in-vitro antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB), and Mycobacterium smegmatis (MC(2)). Among the synthesized compounds, 1-cyclopropyl-1,4-dihydro-7-(3,4-dihydro-6,7-dimethoxyisoquinolin-2(1H)-yl)-8-methyl-6-nitro-4-oxoquinoline-3-carboxylic acid 9p was found to be the most active compound in vitro with a MIC value of 0.39 microM against MTB. Against MDR-TB, compound 7-(2-carboxy-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)-1-cyclopropyl-1,4-dihydro-8-methyl-6-nitro-4-oxoquinoline-3-carboxylic acid 9n was found to be the most active with a MIC value of 0.09 microM.
