Synthesis, Antimicrobial and Antitubercular Activity of Novel Imidazole Carboxamides

Abstract

A series of novel imidazole carboxamide derivatives (6a-j) were synthesized in moderate to good yields via the oxidative esterification of 1H-imidazole-4-cabaldehyde (1) with phenol (4) followed by the aminolysis of various substituted anilines (5a-j) in the presence of 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (2) (IPr, 10 mol%) and TEMPO (3) in toluene. All the compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral data. The synthesized compounds were assessed in vitro for their antimicrobial and antitubercular potential. Among the synthesized compounds 6a, 6f and 6g had significant antibacterial and antifungal activity. Synthesized N-phenyl-1H-imidazole-4-carboxamide (6a) possessed a broad activity spectrum towards S. aureus, B. subtilis, P. aeruginosa, E. coli, A. niger and C. albicans strains employed in the study. The synthesized compounds N-(4-nitrophenyl)-1H-imidazole-4-carboxamide (6e) and N-(3,4-dichlorophenyl)-1H-imidazole-4-carboxamide (6j) demonstrated the maximum antitubercular activity.