Design, Synthesis, and in vitro Anti-mycobacterial Activities of Propylene-tethered Heteronuclear Bis-isatin Derivatives

A series of novel propylene-tethered heteronuclear bis-isatin derivatives were designed, synthesized, and assessed for their in vitro and anti-mycobacterial activities. All hybrids exhibited considerable antibacterial and anti-mycobacterial activities against Mycobacterium tuberculosis H37Rv and multi-drug-resistant tuberculosis (MDR-TB) with minimum inhibitory concentration (MIC) ranging from 16 to 256g/mL. In particular, the heteronuclear bis-isatin 4i (MIC: 25 and 16g/mL) was most active against M.tuberculosis H(37)Rv and MDR-TB strains, which was fourfold and greater than eightfold more potent than the first-line anti-tubercular agents rifampicin (MIC: 64g/mL) and isoniazid (MIC: >128g/mL) against MDR-TB, could act as a lead for further optimization.