Synthesis and antibacterial activity of novel ethyl 2-alkoxyimino-2-benzimidazol-2-yl acetates bearing a morpholine group

In the search for new benzimidazole derivatives with high antibacterial activity and for which bacterial resistance is low, novel ethyl 2-(alkoxyimino)-2-[1-(4-morpholinocarbonylmethyl)-1 H -benzimidazol-2-yl]acetates have been synthesized by multi-step reactions and characterized by 1 H NMR, IR, and ESI–MS analysis. The compounds were evaluated for in-vitro antibacterial activity against Escherichia coli and Staphylococcus aureus . The results revealed that four of the compounds had excellent bioactivity against S. aureus , with IC 50 values of 12.72–26.58 μg/mL, even better than that of the control agent (levofloxacin hydrochloride).