The three-dimensional holographic vector of atomic interaction field（3D-Ho VAIF） is used to characterize the molecular structures of 45 nitroaromatic compounds.Two quantitative structure-toxicity relationship（QSAR...The three-dimensional holographic vector of atomic interaction field（3D-Ho VAIF） is used to characterize the molecular structures of 45 nitroaromatic compounds.Two quantitative structure-toxicity relationship（QSAR） models are built up by stepwise regression（SMR）,multiple linear regression（MLR） and partial least-squares regression（PLS）.The correlation coefficients（R） of the models are 0.960 and 0.961,respectively.Then the models are evaluated by performing the cross-validation with the leave-one-out（LOO） procedure and the correlation coefficients（RCV） are 0.949 and 0.941,respectively.The results show that the descriptors can successfully describe the structures of organic compounds.The stability and predictability of the model are satisfactory.展开更多
Quantitative structure activity relationships(QSARs)were developed for 43 aromatic compounds toxicity to Photobacterium phosphoreum and Daphnia magna based on four methods: octanol/water partition coefficient...Quantitative structure activity relationships(QSARs)were developed for 43 aromatic compounds toxicity to Photobacterium phosphoreum and Daphnia magna based on four methods: octanol/water partition coefficient, linear solvation energy relationship, molecular connectivity index and group contribution. Through the evaluation of four QSAR methods, LSER was proved to be the best. And it applied to the widest range of chemicals with the greatest accuracy.展开更多
The DFT-B3LYP method,with the basis set 6-311G,was employed to calculate the molecular geometries and electronic structures of 45 nitroaromatic compounds.EHOMO、ELUMO、μ、ΔQR and V were selected as quantum chemical ...The DFT-B3LYP method,with the basis set 6-311G,was employed to calculate the molecular geometries and electronic structures of 45 nitroaromatic compounds.EHOMO、ELUMO、μ、ΔQR and V were selected as quantum chemical descriptors.The acute toxicity of these compounds to tetrahymena pyriformis along with the above descriptors was used to establish the quantitative structure-activity relationship(QSAR).The variables were reduced using stepwise multiple regression(SMR)method for the training set,and the statistical results indicated that the correlation coefficient and cross validation using leave-one-out(LOO)were 0.941and 0.862,respectively.To validate the predictive power of the resulting model,external validation was performed with R2ext and Q2extvalues of 0.914 and 0.824,respectively.These showed that the QSAR model had good stability and predictability.The study indicated that the acute toxicity increase with the increase of the volume and the decrease of the energy of the lowest unoccupied orbit.The substituted groups which have strong electron-accepting ability would enhance the toxicity.展开更多
基金supported by the Youth Foundation of Education Bureau,Sichuan Province(13ZB0003)
文摘The three-dimensional holographic vector of atomic interaction field（3D-Ho VAIF） is used to characterize the molecular structures of 45 nitroaromatic compounds.Two quantitative structure-toxicity relationship（QSAR） models are built up by stepwise regression（SMR）,multiple linear regression（MLR） and partial least-squares regression（PLS）.The correlation coefficients（R） of the models are 0.960 and 0.961,respectively.Then the models are evaluated by performing the cross-validation with the leave-one-out（LOO） procedure and the correlation coefficients（RCV） are 0.949 and 0.941,respectively.The results show that the descriptors can successfully describe the structures of organic compounds.The stability and predictability of the model are satisfactory.
文摘Quantitative structure activity relationships(QSARs)were developed for 43 aromatic compounds toxicity to Photobacterium phosphoreum and Daphnia magna based on four methods: octanol/water partition coefficient, linear solvation energy relationship, molecular connectivity index and group contribution. Through the evaluation of four QSAR methods, LSER was proved to be the best. And it applied to the widest range of chemicals with the greatest accuracy.
文摘The DFT-B3LYP method,with the basis set 6-311G,was employed to calculate the molecular geometries and electronic structures of 45 nitroaromatic compounds.EHOMO、ELUMO、μ、ΔQR and V were selected as quantum chemical descriptors.The acute toxicity of these compounds to tetrahymena pyriformis along with the above descriptors was used to establish the quantitative structure-activity relationship(QSAR).The variables were reduced using stepwise multiple regression(SMR)method for the training set,and the statistical results indicated that the correlation coefficient and cross validation using leave-one-out(LOO)were 0.941and 0.862,respectively.To validate the predictive power of the resulting model,external validation was performed with R2ext and Q2extvalues of 0.914 and 0.824,respectively.These showed that the QSAR model had good stability and predictability.The study indicated that the acute toxicity increase with the increase of the volume and the decrease of the energy of the lowest unoccupied orbit.The substituted groups which have strong electron-accepting ability would enhance the toxicity.
