Dibenzofuran, dibenzothiophene and N-methyl carbazole tethered 2-aminothiazoles and their cinnamamides as potent inhibitors of Mycobacterium tuberculosis

Abstract Herein described the design, synthesis and antitubercular evaluation of novel series of dibenzofuran, dibenzothiophene and N -methyl carbazole tethered 2-aminothiazoles and their cinnamamide analogs. One pot condensation of N -methyl carbazole, dibenzofuran and dibenzothiophene methyl ketones with thiourea in the presence of Iodine and CuO gave respective 2-aminothiazoles 4 – 6 in very good yields. Aminothiazoles were further coupled with substituted cinnamic acids using acid-amine coupling conditions to give desired cinnamamide analogs 8a – e , 9a – e and 10a – e . All the newly synthesized compounds were fully characterized by their NMR and mass spectral analysis. In vitro screening of new derivatives against Mycobacterium tuberculosis H37Rv ( Mtb ) resulted 8c , 10d and 10e (MIC: 0.78 µg/mL) and 2-aminothiazoles 5 and 6 (MIC: 1.56 µg/mL) as potent compounds with lower cytotoxicity profile.