用QSAR法研究有机磷农药对海洋扁藻的构效关系

APPLICATIONS OF QSAR TO THE STRUCTURES AND TOXICITIES OF 11 ORGANIC PHOSPHORUS PESTICIDES FOR MARINE PLATYMONAS

1997年3月，利用QSAR构效关系分析方法和计算模拟手段，对中国沿海地区常用的11种有机磷农药对海洋亚心形扁藻的半数抑制浓度进行研究。建立有机磷农药对海洋扁藻致毒效应的QSAR模型：（n＝11，S＝30，R＝0．9606）。模型分析表明，有机磷农药的毒性大小主要受亲脂性、电子密度和立体结构的影响，也是多个因素综合作用的结果。一般说来，有机磷农药亲脂性越强，电于密度越大，立体结构越复杂，对扁藻的致毒效应越大。所建模型不仅相关性较高，而且依此模型估算的EC50预测值与实验值基本相符。说明QSAR分析可以引入到海洋环境毒理领域，作为评价和预测某些有机污染物对海洋生物伤害性的有效方法之一。研究还发现，模型的系数和常数除与物种有关外，是与环境因子-盐度等有关的函数，可以由阐述定量结构-活性相关性扩展到阐述定量环境-结构-活性相关性。

Interrelationships between the structures of 11 orgnic phosphorus peshcides which are offter used in the coastal area of China, and the half effective concentrations of marine Platymonas, were studied by the methods of QSAR and computer analysis in Cktober, 1996. The result can be summarised by 1g(1/EC50) where S is salt content and R is coefficience.An analysis on the basis of the model shows that the toxicities of organic phosphorus peshcides are controlled by the close ablity to ester, electron density and space structure, they are also affcted by other factors. A laree Partition coefficient (lgP), is associated with strong off-waer ablities, a large substituent constant (σ) expressing the electronic effect and a complicated molecular connechvity (1X); these have a serious poisonous effet. The QSAR analysis can be aPPied to the marine environment toxicity field, and be used as an effective method for the assessment and forecashng of the hazard abilities of som contaminate organic compounds for marine cultures. The coefficients and constants from the models are associated with environmental factors, such as the salt content and algae species, therefore, the QSAR method can be used not ouly for the analysis of quanhtative structure-activity relationship, bu also for the analysis of quanhtative environmental-structure-activity relationship (QESAR).