Comparative QSTR Study Using Semi-Empirical and First Principle Methods Based Descriptors for Acute Toxicity of Diverse Organic Compounds to the Fathead Minnow

International Journal of Molecular Sciences

Erol Eroglu¹  Selami Palaz¹  Oral Oltulu¹  Hasan Turkmen² 

[1]Department of Physics, Harran University, Osmanbey Campus, 63300, Sanliurfa, Turkey E-mail:

[2]Department of Chemistry, Harran University, Osmanbey Campus, 63300, Sanliurfa, Turkey E-mail:

关键词: Comparative QSTR;    fathead minnow;    acute toxicity;    DFT;    HF;    AM1;    PM3;   

DOI  :  10.3390/ijms8121265

来源: mdpi

【 摘 要 】

Several quantum-mechanics-based descriptors were derived for a diverse set of 48 organic compounds using AM1, PM3, HF/6-31+G, and DFT-B3LYP/6-31+G (d) level of the theory. LC₅₀ values of acute toxicity of the compounds were correlated to the fathead minnow and predicted using calculated descriptors by employing Comprehensive Descriptors for Structural and Statistical Analysis (CODESSA) program. The heuristic method, implemented in the CODESSA program for selecting the ‘best’ regression model, was applied to a pre-selection of the most-representative descriptors by sequentially eliminating descriptors that did not satisfy a certain level of statistical criterion. First model, statistically, the most significant one has been drawn up with the help of DFT calculations in which the squared correlation coefficient R² is 0.85, and the squared cross-validation correlation coefficientin the third case are correspondingly 0.79 and 0.66, whereas in the fourth case they are 0.78 and 0.65 respectively. Results of this study clearly demonstrate that for the calculations of descriptors in modeling of acute toxicity of organic compounds to the fathead minnow, first principal methods are much more useful than semi-empirical methods.

【 授权许可】

Unknown   
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