Niederer Christian, Goss Kai-Uwe
Institute of Biogeochemistry and Pollutant Dynamics, ETH-Zurich, Universitätsstrasse 16, CH-8092 Zurich, Switzerland.
Chemosphere. 2008 Mar;71(4):697-702. doi: 10.1016/j.chemosphere.2007.10.055. Epub 2008 Feb 20.
Chlorophenol isomers are known to possess substantially different octanol/water and octane/water partition constants depending on whether the chlorine substituents are in the ortho or meta/para position. Here we show that the same is also true for environmental partition processes such as water/air and humic acid/air partitioning. Quantitative structure property relationships (QSPR) such as those in the widely used EPI-suite or SPARC fail to correctly predict this influence of the substituent position on the compound's partitioning. Only a more sophisticated quantum chemical software, called COSMOtherm, correctly reproduced these effects. Based on this and earlier experiences we conclude that COSMOtherm may be a better tool for screening large sets of chemicals for which no experimental data on their partitioning yet exist.
已知氯酚异构体具有截然不同的辛醇/水和辛烷/水分配常数，这取决于氯取代基是处于邻位还是间位/对位。在此我们表明，对于水/空气和腐殖酸/空气分配等环境分配过程而言，情况亦是如此。诸如广泛使用的EPI-suite或SPARC中的定量结构-性质关系（QSPR）无法正确预测取代基位置对化合物分配的这种影响。只有一种更复杂的量子化学软件COSMOtherm能够正确再现这些效应。基于此以及早期经验，我们得出结论，对于尚未有分配实验数据的大量化学品进行筛选，COSMOtherm可能是一个更好的工具。
