Synthesis And Promoting Cell Division Activity Of Phenyl Urea Derivatives

Phenyl urea derivatives are a kind of novel farming materials which were synthesized in the 1970s. At present, these compounds are mainly synthesized by two routes, the phosgene method and the oxalyl chloride method. Phenyl urea derivatives have wide-ranging biological activities. In agriculture production, they are chiefly served as the crops' insecticides, bactericides, weeds' killers and plant growth regulators. Among these regulating the flora cell growth is the most fascinating activated feature. In this dissertation, the synthesis and cell division activation of phenyl urea derivatives have been wholly researched. Their recent advances hi the relevant research were reviewed as well.Either aniline or substituted aniline acted as the fundamental material, the methyl chloroformate synthesis method was used to synthesize eight kinds of diphenyl urea compounds. They were N,N'-diphenyl urea, N-phenyl-N'-(3-nitrophenyl)urea, N-phenyl-N'-(4-methylpheny-l)urea, N-phenyl-N'-(2-methylphenyl)urea, N-phenyl-N'-(3-methylph enyl)urea, N-phenyl-N'-(2-chlorophenyl)urea, N-phenyl-N'-(3-chlorophenyl)urea and N-phenyl-N'-(4-chlorophenyl)urea respectively. The structures of synthetic compounds and target compounds have been elucidated with infrared spectrum and mass spectra. Two step of reactions were included in the general synthesis. Firstly, aniline or substituted aniline reacted with methyl chloroformate in tri-n-butylamine solvent or triethylamine solvent to generate substituted aniline-methanoate, then without any further separation the latter continued to react directly with excessive aniline or substituted aniline, and target compounds were obtained. In the research, it was found that , if the products with electron-withdrawing groups and the products of electron-repelling groups were concerned, the order to add raw materials should be different. To get target compounds in high production, the aniline substituted with electron-withdrawing group should be added in first step of reaction, but the aniline substituted with electron-repelling group should be added in second step of reaction. The orthogonal experiments with two factors and three levels in each during the second step of reaction were investigated. The result showed that,for the substituted aniline, methyl chloroformate, triethylamine and aniline, the optimal constituents ratio among them(mol/mol) is 1.0 : 1.5 : 1.5 : 1.5. The optimal reaction temperatures for the target compounds I-VIII are 120℃, 152℃, 165℃, 162℃, 155℃, 170℃, 158℃ and 165℃ respectively, and their optimal reaction duration are 3.0 h, 4.0 h, 5.0 h, 5.5 h, 4.0 h, 4.5 h, 4.0 h and 5.0 h respectively. Compared with the conventional methods-the phosgene method and the oxalyl chloride method, the present method-methyl chloroformate method, took the advantages of simple devices, less procedures, convenient post-treatment, higher yield, less environmental pollution etc. It is available for laboratory and industrial production.Using the seeds of Radish Fengguang as material, the biological activities of the above synthesized compounds in promoting cell division were investigated by the method of radish cotyledon stretching growth. The result showed that all the above compounds could promote radish cotyledon growth in the range of 0.01mg/L and 1.0mg/L. Furthermore, for the N-phenyl-N'-m-nitro phenyl urea, the highest biological activity appeared in the concentration of 1.0 mg/L. Compared with the products of electron-repelling group, the products of electron-withdrawing group displayed higher biological activity. For the same kind of groups, the biological activities decreased in the order of meta-, ortho-, para-substituted analine.