Synthesis and potent antimicrobial activity of some novel methyl or ethyl 1H-benzimidazole-5-carboxylates derivatives carrying amide or amidine groups Original Research Article

A series of benzimidazole-5-carboxylic acid alkyl ester derivatives carrying amide or amidine substituted methyl or phenyl groups at the position C-2 were synthesised and evaluated for antibacterial and antifungal activities against S. aureus, methicillin resistant S. aureus (MRSA), S. faecalis, methicillin resistant S. epidermidis (MRSE), E. coli and C. albicans. The results showed that while all simple acetamides are essentially inactive, aromatic amides and amidines have potent antibacterial activities. Aromatic amidine derivatives 13f–h exhibited the best inhibitory activity with 1.56–0.39 μg/mL MIC values against MRSA and MRSE.