MtTMPK-IN-1 (compound 3) is a potent Mycobacterium tuberculosis thymidylate kinase ( Mt TMPK) inhibitor with an IC 50 value of 2.5 μM. MtTMPK-IN-1 has moderate to weak activity against Mtb H37Rv and low cytotoxicity in human fibroblast cells MRC-5. MtTMPK-IN-1 can be used for researching tuberculosis.