Synthesis Of Benzimidazoles Compounds And Wood Preservation Research

Benzimidazole derivatives have good bactericidal activity, mould resistanceactivity and possess a variety of other characters. To find new hyperactivitybroad-spectrum organic wood preservative, seven5-substituted benzimidazolecompounds were synthesized from4-substituted o-phenylenediamine throughmulti-step reactions including acylation, cyclization and so on. All the structureswere confirmed by melting points, MS,1H NMR and elemental analysis. The targetcompounds were screened for antimicrobial activity by agar-well diffusion methodagainst white-rot fungus (Coriolus versicolor), brown-rot fungus (Gloeophyllumtrabeum) and moulds (Aspergillus niger and Trichoderma viride). Then, this paperstudies on them laboratory anti-mould performance and leaching resistanceevaluation, they have the distinct advantages compared with the traditionalanti-mould. The contents and the primary contributions of the research aresummarized as follows:1. Seven5-substituted benzimidazole compounds were synthesized from4-substituted o-phenylenediamine through multi-step reactions including acylation,cyclization and so on, and in which two have never been reported by now, the salientfeatures of the above mentioned methods include a simple procedure, mildconditions and easy purification.2. The antibacterial properties of fungi of the target compounds were testthrough the zone of inhibition. Results show that: all compounds showed their nofungicidal activities, but some showed their anti-mould activities, and even somebetter than the contrast.3. Laboratory anti-mould performance was carried on to evaluate mouldresistance using the concentration of different target compounds solution, the resultsshow that0.5%4a and1.5%4b could obtain grade0anti-mould, better thanpentachlorophenol sodium.4. Laboratory leaching performance was carried on to evaluate leaching rate of1.0%,1.5%concentration of target compounds and pentachlorophenol sodium, theresults show that the leaching rate of target compounds4b is the lowest in the sameexperimental conditions, which1.5%4b is only to8.31%, better than4a(carbendazim) and pentachlorophenol sodium.