摘要
Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structureproperty relationship (QSPR) model for predicting n-octanol/water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest occupied molecular orbital (EHOMO), the most negative atomic partial charge (q^-) and average molecular polarizability (a), of which R^2= 0.9011 and SD = 0,17 with larger t values. In addition, the variation inflation factors (VIF) of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test (q^2 = 0.8688) and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (Cv^0), of which R^2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively.
Optimized calculation of dibenzofuran (DF) and 135 polychlorinated dibenzofurans (PCDFs) was carried out at the B3LYP/6-31G* level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structureproperty relationship (QSPR) model for predicting n-octanol/water partition coefficients (lgKow) of PCDFs. The new model of lgKow achieved in this work contains three variables: energy of the highest occupied molecular orbital (EHOMO), the most negative atomic partial charge (q^-) and average molecular polarizability (a), of which R^2= 0.9011 and SD = 0,17 with larger t values. In addition, the variation inflation factors (VIF) of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test (q^2 = 0.8688) and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility (-lgSw) has high relative correlation with constant volume molar heat capacity (Cv^0), of which R^2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively.
基金
This work was supported by the China Postdoctoral Science Foundation (No. 2003033486)