Synthesis and Antimycobacterial Assays of Some New Ethambutol Analogs.

Ethambutol (EMB) is a first-line anti-tuberculosis drug that is also considered in treatment regimens for infections caused by non-tuberculous mycobacteria (NTM). EMB targets the arabinosyl transferases EmbCAB, which are important for the synthesis of cell wall constituents. To further explore and narrow down the structural variability of EMB, we synthesized three series of new EMB analogs. We tested their activity against Mycobacterium tuberculosis, Mycobacterium smegmatis, Mycobacterium abscessus and Mycobacterium intracellulare. Only analogs that very closely resembled EMB showed comparable antimycobacterial activity.