Toxicity Prediction of Dioxins and Dioxin-like Compounds Based on the Molecular Fragments Variable Connectivity Index

The toxicity of 95 doxins and dioxin-like compounds was investigated by quantitative structure–activity relationship (QSAR) with the molecular fragments variable connectivity index (mfVCI). For each of the four homologues, the models have good fitting ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ R^{2} > 0.80 $$\end{document}) and predictive (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ Q_{EXT}^{2} > 0.80 $$\end{document}) ability. The models developed from more than one homologues are also satisfactory with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ R^{2} > 0.80 $$\end{document} and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ Q_{EXT}^{2} > 0.77 $$\end{document}. The molecular fragments weights have the ability to diagnose the contribution of the molecular fragments to the toxicity of the compounds. The mfVCI may play an important role in the development of molecular descriptors in further QSAR research.