具有除草活性的3-(嘧啶基-2)-1,3,4-噁二唑-2(3H)-酮衍生物的设计、 合成与定量构效关系的研究

设计合成了一系列未见文献报道的5-叔丁基-3-4-取代-5-(氢)甲基嘧啶-2-基]-1,3,4-噁二唑-2(3H)-酮的衍生物, 其结构均经过1H NMR, IR和元素分析表征. 生测结果显示, 部分化合物表现出较好的除草活性. 定量的结构与活性关系研究表明, 它们的除草活性与取代基的立体效应参数和电性参数呈现很好的相关性, 相关系数r大于0.8. 当作用对象为油菜时, 化合物的活性可能主要与取代基R2的邻位立体效应参数Es和电性参数相关; 当作用对象为稗草时, 化合物的活性主要与取代基R2邻位立体效应参数Es和间位取代基电性参数相关.

Design, Synthesis and Quantitative Structure-Activity Relationship Study of Herbicidal Analogues of 3-(Pyrimidin-2-yl)-2,3- dihydro-1,3,4-oxadiazol-2-ones

A series of 5-tert-butyl-3-(pyrimidin-2-yl)-2,3-dihydro-1,3,4-oxadiazol-2-one derivatives were designed, synthesized and structually confirmed by 1H NMR, IR spectra and elemental analysis. The bioassay results showed that some of these compounds exhibited good herbicidal activity. Quantitative structure-activity relationship studies showed that their herbicidal activity was correlated with the steric and electronic physicochemical parameters, where the correlation coefficients were larger than 0.8. The herbicidal activity against Brassica campestris was mainly effected by the Es of ortho-R2 and the electronic parameter of R2. The herbicidal activity against E. crus-galli was mainly related with Taft (Es) of the ortho-R2 and the electronic parameter of the meta-R2.