| Herbicide plays an irreplaceable role in agricultural production, but some herbicides with high herbicidal activity have been limited or prohibited to use because of their own toxicities and negative impacts on the environment, so, high efficient, low toxic and biodegradable green chemical pesticides become the focus of Pesticide researchers'attention. Carbohydrate is a kind of adaptive molecules in vivo, which almost involved all life processes in vivo, they are important bioactive substances. This thesis present the ultimate degradation products of chitin—2-deoxy-β-D-glucosamine to modify herbicide functional molecules, after chemical modification, we introduced sugar molecular into the structure of urea herbicide, synthesized a series of N-2-deoxy-β-D-glucosyl urea derivatives and then evaluated the herbicidal activities of these compounds. Contents and results of this thesis are as follows:1. To use 2-deoxy-β-D-glucosamine hydrochloride as raw materials, after hydroxyl protection, acylation and other steps, we obtained 14 N-2-deoxy-β-D-glucoyl urea derivatives by isocyanate method, of which 10 species have not been reported, and the compounds were characterized by IR,1HNMR. Structured as follows: A1R:3,4-dimethyl-phenyl A5R:3-chloro-4-methyl-phenyl A12R:3-methyl-phenyl A2R:2,4-dimethyl-phenyl A6R:2-fluoro-phenyl A9R:N-methyl phenyl A13R:4-methyl-phenyl A3R:3,5-dimethyl-phenyl A7R:2-pyridyl A10R:n-(Bu)2- A14R:4-ethoxy-phenyl A4R:2-4-ethoxy-phenyl A8R:3-pyridyl A11R:phenyl2. We selected monocotyledon Sorghum sudanense Stapf. and Lolium perenne L., dicotyledon Brassica campestris L. and Amaranthus albus L. as tested crops, then conducted preliminary herbicidal activity tests by the plate method to the synthesized 14 compounds in 25μg/mL,50μg/mL,100μg/mL and 200μg/mL 4 gradient concentrations, and analyzed the correlation between the concentrations and growth inhibition rates. The preliminary results showed that the herbicidal activity of the compounds varied with the differences of alkyls, pharmaceutical concentrations and tested crops varieties, however, all the compounds showed an inhibitory effect to growth of the tested crops at tested concentrations, particularly at high concentration. And by compared the data of each group, we knowed that the inhibitory effects of compounds on root growth were better than on sprout, on monocotyledon better than on dicotyledonous. Shown as the activity data:(1) The calibrated root length inhibition rate of Sorghum sudanense Stapf. exceeded 80% at 200μg/mL of every compound, which, the calibrated root length inhibition rate reached over 90% at 100μg/mL of compound A6;(2) The calibrated root length inhibition rate of Lolium perenne L. exceeded 70% at 200μg/mL of every compound, which, the calibrated root length inhibition rate reached 90% at 100μg/mL of compound A7;(3) The calibrated root length inhibition rate of Amaranthus albus L. reached over 70% at 100μg/mL of A2, A3, A7, A11 and A13;(4) The calibrated root length inhibition rate of Brassica campestris L. exceeded 70% at 100μg/mL of A3, A6, A7 and A13.3. We selected compound A1, A3, A13 and A14 to deprotect the acetyls on sugar ring and got B1, B3, B13 and B14. We conducted herbicidal activity tests under the same condition as compounds A, according to the rusults of comparation, we got following conclusions:when the compounds B had electron-attracting groups on benzene, the inhibitory activity would be raised; when had electron-rejected groups, the conclusion might be different because of the substituents'places. So, the relationship between the herbicidal activity with the deprotection of the acetyls on sugar ring or not needs further studies.The idea of modified urea with sugar is consistent with the development trend of green chemical pesticide. The related reseach to modify urea with sugar is of great significance on riching urea pesticide structure theory and on exploring new leader compounds.
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