Investigation of the Antimycobacterial Activity of 8-Hydroxyquinolines

A series of styrylquinolines and quinolineamides based on the 8-hydroxyquinoline moiety were investigated as potential antimycobacterial agents. The lipophilicity of the compounds was measured using RP-HPLC and the tests of their activity against Mycobacterium kansasii, the M. avium complex, M. smegmatis, M. abscessus, M. tuberculosis and M. avium paratuberculosis was performed. Several of the compounds that were obtained appeared to be more effective than isoniazid and ciprofloxacin. The 5,7-dinitro-8-hydroxyquinoline derivative possessed the highest potency against M. abscessus and M. Smegmatis, which was about twice as effective as ciprofloxacin, while 2-(2-hydroxystyryl)-8-hydroxyquinoline-7-carboxylic acid appeared to be comparable with the standard drugs that are against the M. avium complex. The structure activity relationships are discussed.