Synthesis And Antimicrobial Evaluation Of Amino-Guanidine Derivatives Containing Benzyloxy And Benzylidene As Novel Potential Antibacterial Agents

The bacterial infection is a common clinical disease currently. It has been a hot issue for the researchers to research and develop the antibacterial drugs. Many kinds of potent antibacterial drugs have been produced which alleviates the pain and saves life of many people. However, clinically abuse of antibiotics can lead to drug-resistant bacteria and gradually reduce the cure rate of the existing antibacterial agents which make the demand for new antimicrobial agents obvious in the market. Therefore, it is very necessary to search novel compounds with stronger antibacterial activity against resistant bacteria.To obtain a stronger antibacterial activity, three series of Amino-guanidine derivatives (3a-g,6a-f and 9a-j) were synthesized, characterized, and evaluated for their antimicrobial activity. Most of the synthesized compounds showed potent inhibition against several Gram positive bacteria (including multiple-resistant clinical isolates) and E.coli 1924, E.coli 1356 with MIC values in the range of 1-32 μg/ml.In particular, compounds 3d and 9d showed excellent antimicrobial activity at MIC 1μg/ml.Compounds 3a-g and 6a-f showed some antimicrobial activities against pseudomonas aeruginosa 2004 and 2742. Compounds3a,3b,3d,3c,3f,3g and 6d showed antimicrobial activity against pseudomonas aeruginosaat MIC 8μg/ml. Compounds 3a-g also showed antimicrobial activity against salmonella typhimurium 2421. Compounds 3d,3e,3f and 3g showed antimicrobial activity against salmonella typhimurium at MIC 8μg/ml. All compounds were characterized by IR,1H-NMR,13C-NMR and MS spectra.