Synthesis And Antibacterial Activities Of Benzimidazole Multi-schiff Base Compounds

Benzimidazole compounds and Schiff base compounds have good biological activities and possess a variety of other characters. To find new hyperactivity broad-spectrum fungicide compounds and study the relationship between structure and biological activities of these compounds, This paper designs and synthesises of a new type of mother-benzimidazole compounds containing multi-imine structures according to principles of drug together,at the same time, changes substituent group and the substituent group position of aldehyde or ketone, bonds the two biological activity groups together, it maybe show more typical biological activity and other properties, Desire to select out new active benzimidazole compounds. This paper is mainly consisted of several parts as followed:1,the recent advances in the synthesis and application of benzimidazoles derivatives and Schiff bases are reviewed. and prospect of application for them were also discussed.2,Two 2-substituted benzimidazoles derivatives were synthesized by the reaction of o-phenylenediamine with corresponding carboxylic acid in hydrochloric acid under microwave irradiation.The effects of the mole ratio of materials,output power of microwave,reaction time on yield were discussed. We could receive the best reaction condition:o-phenylendiamine: 2-(3,5-Dinitro-phenyl)-1H-benzoimidazole is 1:2(mole ratio),output power is 300 W,the reaction time is 30min,sulfuricacid anhydrous is sodium sulfate ,the total yield is 94%.The salient features of the above mentioned methods include a simple procedure,mild condiitons,shorter reaction time,and easy purification3,In the best condition,a series of new compounds were prepared. All the compound synthesized were confirmed by elemental analyses, 1H NMR, IR, and mass spectral data.4,To study the relationship between structure and effect of these compounds, the antimicrobial activity to pathogens were considered. All compounds synthesized were tested in vitro against five fungicide:Fusarium oxysporium , Alternaria solani , Fusarium graminearum,Cercospora sorghi Fusaurium oxysporiumf. sp.vasinfectum incomparison with 50% carbendazim wet powder. The relationship between the structures and the fungicidal activities of the compounds was discussed.The main results are as follows: All compounds showed their fungicidal activities, some showed better activities than the contrast. The contrast on the inhibition of plant pathogenic fungi has a broad-spectrum character, but most synthesis benzimidazole multi-schiff base compounds on the inhibition of plant pathogenic fungi don't have broad-spectrum characters. The inhibitory activity of compounds E,G to Fusarium oxysporium, compounds E,F,G,I,L to Alternaria solani, compounds C,E,F,G,I,J to Fusaurium graminearum. sp.vasinfectum , compoundsB,C,E,G,K to Fusarium graminearum, compounds C,D,E,F,G,I,K,L to Cercospora sorghi are significantly higher than the contrast.On the whole, The inhibitory activity of compounds E,Gto plant pathogenic fungi are significantly higher than the contrast,and The inhibitory activity of compounds H,N,M to plant pathogenic fungi are relatively weak.