2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative as efflux pump inhibitor in Mycobacterium tuberculosis.

Although the administration of combined therapy is efficient to tuberculosis (TB) treatment caused by susceptible Mycobacterium tuberculosis strains, to overcome the multidrug resistance is still a challenge. Some studies have reported evidence about tetrahydropyridines as a putative efflux pump inhibitor, including in mycobacteria, being a promising strategy against M. tuberculosis. Thus, we investigated the biological potential of 2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative (NUNL02) against two strains of M. tuberculosis. NUNL02 was able to increase the susceptibility of the multidrug resistant strain to the anti-TB drugs, resulting in synergism with rifampicin. Still, we assume that this compound plays a role in the efflux mechanism in M. tuberculosis, besides, to be able to kill the bacillus under the deprivation of essential nutrients. Thus, our findings highlight NUNL02 as a promising prototype to develop a new adjuvant for TB treatment, mainly as EPI.