Green Synthesis And Preliminary Antibacterial Activity Of Benzimidazole Derivatives

Benzimidazole was important intermediated products which had been used in medicine, it had extensive and important activities due to special structure, so it is very important to synthesize a series of new benzoimidazoles in new drug development and biochemistry research. In this paper, so many innovative methods were used in benzimidazole technology synthesis, a series of new benzimidazole compounds were synthesized by the reaction under microwave irradiation using ionic liquid [Etpy] BF4 as the catalyst then confirmed structure by 1H NMR, IR or MS and study the antimicrobial activities.1. The green condition of the synthesis of benzoimidazole:Ionic liquid [Etpy]BF4 was used as the catalyst, alcohol was used as solvents, M(o-phenylenediamine):M(aldehyde): M([Etpy]BF4)= 1:1:0.2, microwave power of 500 W and irradiation time of 2 h under 25℃, put the reaction solution into an amount of ice water to get crude product, and then recrystallized, the conversion rate was 90.8%. The synthesized compound was characterized and confirmed by IR,1H NMR and MS.2. Twelve benzimidazole compounds were synthesized by [Etpy] BF4 under microwave irradiation according to the green condition, the structures of twelve benzimidazole compounds were confirmed by 1H NMR, IR or MS.3. The preliminary antibacterial activity of twelve benzimidazole compounds were studied. Results showed that B10-B12 compounds showed greatest antimicrobial toward both gram-positive and gram-negative bacteria, the most sensitive stains were Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas Aeruginosa with MIC value of 1 mg/mL, MBC value of Escherichia coli were 4 mg/mL, inhibition zone of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas Aeruginosa were above 1.5 mm.