嘧啶苯磺酰脲衍生物对小麦纹枯病菌体外抑菌活性的QSAR研究与分子设计

QSAR Study on the Antifungal Activity of Pyrimidin-Phenyl Sulfonylurea Derivatives to Rhizoctonia Cerealis and Their Molecular Design

目的:建立嘧啶苯磺酰脲衍生物(PSU)对小麦纹枯病菌杀菌活性(T_c)和电性距离矢量(E_v)的定量构效关系(QSAR)模型,探讨影响T_c的结构因素.方法:基于拓扑方法计算了15种嘧啶苯磺酰脲衍生物的电性距离矢量.通过最佳变量子集回归建立这些化合物的T_c与E_v的多个QSAR模型.结果:其中最佳三元数学模型的判定系数(R^2)及逐一剔除法的交叉验证相关系数(R_(cv)~2)分别为0.851和0.738.经统计指标诊断,所建模型具有良好的稳健性及预测能力.结论:根据进入此模型的E_(62),E_(59)和E_(27)可知,影响嘧啶苯磺酰脲衍生物对小麦纹枯病菌杀菌活性的主要因素是分子的二维结构特征—NH—,≥S≤,—OH,—CH_g<(g=0,1)和>C<等结构碎片.由结构修饰提出3种化合物的抑菌活性(T%)均超出96.5%,有待以后生物实验予以证实.

Objective： To study the quantitative structure-activity relationship （QSAR） between the antifungal activity （Tc） and the electronegativity distance vector （Ev ） of 15 pyrimidin-phenyl sulfonylurea derivatives （PSU） , and analyze the dominant influence structural factors of antioxidant activities. Method： The electronegativi- ty distance vector （Ev ） of PSU were calculated by the topological method. The QSAR models were established by using leaps-and-bounds regression analysis for the antifungal activity （ Tc ） of above compounds in vitro against Rhizoctonia cerealis along with the Ev. Results： The traditional correlation coefficient （R2） and the cross-validation correlation coefficient （R^2cv） of leave-one-out （LOO） are 0.85l and 0. 738, respectively. The QSAR model has both favorable estimation stability and good prediction capability by statistical index tests. Conclusion： From E62, E59, E27 in the model, it shows that the main factor to affect the antifungal activity of pyrimidin-phenyl sulfonylurea derivatives is a two-dimensional structural characteristics of the molecular --NH--, ≥S≤, --OH,--CHg 〈 （g=0,1） and 〉C〈 structure inhibition activity （ T% ） of three logic experiments. fragments. According to the results obtained from the structural modifications, the modified molecules is over 96.5%, and it is expected to be confirmed by using biologic experiments.