Design, synthesis and antibacterial activity of some pyrrolo[3,4-b]quinolin-2(3H)-yl)benzamide derivatives

Emerging infectious diseases and the increasing number of multi-drug resistant microbial pathogens still make the treatment of infectious diseases an important and challenging problem[1]. Therefore, there is an urgent need for development of new antibacterial and antifungal agents with divergent and unique structure and with a mechanism of action possibly different from that of existing antimicrobial agents[2]. The pyrrolo[3,4-b]quinoline ring system is present in compounds associated with a wide variety of pharmacological properties as is exemplified with hypnotic and cytotoxic effects, and with analgesic and antiviral activities [3].In this study, a series of new pyrrolo[3,4-b]quinolin-2(3H)- yl)benzamide derivatives (7a-g) was synthesized by reaction of benzohydrazide derivatives (6a-g) with 9-phenylfuro[3,4-b]quinoline-1,3-diones (5a-b) in the presence of Et3N and evaluatedfor their antibacterial activity against various bacterial strains using in vitro disc diffusion methodby measuring the zone of inhibition. Most of the compounds exhibited potential antibacterial activity against gram-negative (Escherichia coli) and gram-positive bacteria (Streptococcus and Enterococcus).