Mt KARI-IN-2 (compound 5b) is a highly effective inhibitor of Mycobacterium tuberculosis ketol-acid reductoisomerase (Mtb KARI), with a Ki value of 2.02 μM. This compound also exhibits inhibitory activity against Mtb H37Rv, with a MIC value of 0.78 μM. Moreover, Mt KARI-IN-2 demonstrates low cytotoxicity, as evidenced by a HEK IC 50 greater than 86 μg/mL [1].