Structure-activity relationships of 2-aminothiazoles effective against Mycobacterium tuberculosis.

ABSTRACT: A series of 2-aminothiazoles was synthesized based on a HTS scaffold from a whole-cell screen against Mycobacterium tuberculosis (Mtb). The SAR shows the central thiazole moiety and the 2-pyridyl moiety at C-4 of the thiazole are intolerant to modification. However, the N-2 position of the aminothiazole exhibits high flexibility and we successfully improved the antitubercular activity of the initial hit by more than 128-fold through introduction of substituted benzoyl groups at this position. N-(3-Chlorobenzoyl)-4-(2-pyridinyl)-1,3-thiazol-2-amine (55) emerged as one of the most promising analogues with a MIC of 0.024?M or 0.008?g/mL in 7H9 media and therapeutic index of nearly ?300. However, 55 is rapidly metabolized by human liver microsomes (t1/2=28min) with metabolism occurring at the invariant aminothiazole moiety and Mtb develops spontaneous low-level resistance with a frequency of ?10(-5).

SUBMITTER: Meissner A 

PROVIDER: S-EPMC3816974 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature