The antimycobacterial activity of new 18 7-chloroquinoline derivatives, obtained from 4,7-dichloroquinoline, was evaluated against 15 Mycobacterium spp among standardized and clinical isolates using the MTT susceptibility test to obtain minimum inhibitory concentration values (MIC, μg/mL). The results suggested that 7-chloroquinoline compounds are useful leads for new anti-TB drug development. The most active compounds exhibited moderate activity with 16 μg/mL MIC values for all tested microorganisms. Keywords: 7-Chloroquinoline derivatives, Synthesis, MDR-TB, Antimycobacterial activity, Tuberculosis (TB), Mycobacterium tuberculosis, human immunodeficiency virus (HIV), rifampin (RMP), isonicotinylhydrazine, INH, Heterocyclic systems, quinine, chloroquine, primaquine, amodiaquine