Synthesis and anti-mycobacterial activities of triazoloquinolones

A number of quinolone derivatives have been reported to possess anti-mycobacterial activity. Generally.
Mycobacterium tuberculosis isolates expressing resistance to both isoniazid and rifampin are susceptible
to fluoroquinolones. Benzotriazole is a hetero-bicyclic aromatic ring endowed with interesting chemical
and biological properties and pharmacological activities. In a preliminary study we have recently
reported the activity of triazolo[4,5-h]quinolone-carboxylic acids, a new class of benzotriazole derivatives active against multi-drug resistant M. tuberculosis (MDR-Mtb). In this study we confirm that this
novel class of quinolones is endowed with a selective anti-mycobacterial activity, coupled with absence
of cytotoxicity.
The SAR analysis of the new derivatives in comparison with the previous series shows that the methyl
group is the most effective substituent in both N-3 and N-9 positions of the ring system.