氯代苯类化合物对江水细菌的毒性及QSAR研究

QSAR for the Toxicity of Chlorobenzenes to River Bacteria

采用细菌生长抑制实验,测定了18种氯苯类化合物对长江水中混合细菌的毒性,得到24 hIC50值,-1gIC50为3.65～4.32,其中,毒性最弱的是氯苯,毒性最强的是1,2,4-三氯苯.选用分子连接性指数法对毒性数据进行定量结构活性关系(QSAR)研究.结果表明,氯苯类化合物对江水细菌的毒性与苯环上取代基的种类、数目和位置有关,价分子连接性指数0XV和7XCHV能够很好地描述氯苯类化合物对江水细菌的毒性.方程-1gIC50=0.8390XV-25.3727XCHV+0.802的稳健性很好,该模型的预测值与毒性实测值之间的相关系数达0.948.

The toxicity 24 h IC50 of 18 chlorobenzenes to the bacteria in the Yangtze River was determined by using the bacteria growth inhibition test, and the range of -1g IC50 was from 3.65 to 4.32, in which the least toxic compound was chlorobenzene and the most toxic compound was 1,2, 4-trichlorobenzene. The quantitative structure-activity relationship （QSAR） models were developed for the toxicity by using the molecular connectivity index method. The toxicity of chlorobenzenes to the river bacteria is related to the kinds, amount and position of the substituents in benzene ring. The valence molecular connectivity index^0 X^v and^7 XCH^v can well describe the toxicity of the compounds under study, The equation -1g IC50 = 0.839 ^0 X^v- 25.372^7 XCH^v ＋ 0. 802 is stable enough to predict the toxicity, and the correlation relationship between the predicted and observed toxicity is up to 0.948.