文摘
The DFT-B3LYP method, with the basis set 6-31G (d, p), was employed to calculate some quantum chemical descriptors of 43 halogenated phenols compounds. The above descriptors along with the octanol-water partition coefficient were used to establish the quantitative structure activity relationship (QSAR) of the toxicity of these compounds to tetrahymena pyriformis by multiple linear regression (MLR) and support vector machine (SVM). The statistical results indicate that the multiple correlation coefficient (R2) and cross validation using leave-one-out were 0.922, 0.892 and 0.944, 0.924, respectively. To validate the predictive power of the resulting models, external validation multiple correlation coefficient and cross validation (Q2ext) were 0.975, 0.919 and 0.957, 0.934, respectively. These show that the QSAR models have both favourable estimation stability and good prediction power. The results indicate that there are good correlations among the acute toxicity of halogenated phenols to tetrahymena pyriformis and the octanol-water partition coefficient, highest occupied molecular orbital, dipole moment, the sum of halogenated electric charges.