Abstract: The present invention concerns new tricyclic spirolactams (TriSLas) compounds and their use as a drug, in particular for the prevention and/or treatment of a mycobacterial infection or for the treatment of a disease caused by infection with a Mycobacterium. The tuberculosis drug development pipeline requires further supplementation with additional candidates, ideally acting on novel targets (to minimize cross-resistance) and impacting on drug-tolerant bacilli to shorten treatment. The inventors of the present invention have identified new tricyclic spirolactams (TriSLas) compounds with particular activity against M. tuberculosis.