The Pyrimidine Acylthiourea Synthesis, Structure, Biological Activity, Thermodynamics And Quantum Chemical Study

Acylthiourea derivatives have been widely researched because of their broad insecticidal, anti-fungal, anti-virus, herbicide and plant growth regulating properties during the past two or three decades. These compounds have unique mechanism and have higher biological selectivity, are more safe for environment, and degrade much faster than the traditional pesticides. So they are servered as "the twenty-first century pesticides." In recent years this type of compounds have been studied widely because they also can diminish inflammation, anti-allergic, anti-virus and anti-bacterial. Therefore, acylthiourea derivatives have become a hot research in the medicine and pesticides.In this paper, seven compounds and another three Cu(Ⅱ) complexs were synthesized as show below:Ⅰ:N-p-methoxylbenzoyl-N'-(4,6-dimethyl-pyrimidin-2-yl)thioureaⅡ:N-p-methoxylbenzoyl-N'-(pyrimidin-2-yl)thioureaⅢ:N-ethoxylacyl-N'-(4-methoxyl-6-chlorine-pyrimidin-2-yl)thioureaⅣ:N-methoxylacyl-N'-(4-amido-6-chlorine-pyrimidin-2-yl)thioureaⅤ:N-ethoxylacyl-N'-(4-amido-6-chlorine-pyrimidin-2-yl)thioureaⅥ:N-benzoyl-N'-(4-amido-6-chlorine-pyrimidin-2-yl)thioureaⅦ:N-p-methoxyIbenzoyI-N'-(4-amido-6-chlorine-pyrimidin-2-yl)thiourea Complex:Cu(L₁)₂Cl₂ L₁:N-ethoxylacyl-N'-(4,6-dimethyl-pyrimidin-2-yl)thiourea Complex: [Cu(L₂)₂Cl₂]·2L L₂:N-p-methoxylbenzoyl-N'-(4,6-dimethoxyl-pyrimidin-2-yl)thiourea Complex: Cu(L₃)₂Cl₂ L₃:N-methoxylacyl-N'-(4,6-dimethoxyl-pyrimidin-2-yl)thioureaThese compounds were determined by elemental analysis,IR and H¹NMR, their single crystal structures were obtained by slow evaportion of a solvent at room temperature and determined by X-ray diffraction.The bioactivity of the compounds (Ⅰ,Ⅱ,Ⅲ,Ⅳ) were studied by microbe of Apple anthracnose colletotrichum and Tomato botrytis cinerea, and the effects of compounds (Ⅰ, Ⅱ,Ⅳ,Ⅴ,ⅥandⅦ) on wheat growth were studied, too. In this paper, the relationship between the structure and bioactivity has also been researched.The specific heat capacity of several compounds were determined by a microcalorimetry method within 283-353 K,and their thermodynamic functions were obtained. The thermal behavior of these compounds were studied by the DSC and TG/DTG techniques. This can provides essential and reliable bascial date for theoretical research and engineering.The experimental geometries of N-benzoyl-N '-(pyrimidin-2-yl)thiourea and compoundⅠwere fully optimized with Gaussian 03W. The relationship between the atomic charges, the percentage of frontier orbital compositions and bioactivity were discussed.