Modeling the Interaction of Small Organic Molecules with Biomacromolecules (the Oasis Approach). V. Toxicity of Phenols to Algae “Lemna Minor”

Abstract

AbstractThe recently developed OASIS approach See Refs. 1 to 4 for Parts I to IV of this series, as well as Refs. 6 and 7 for a detailed description of the approach. is applied to the modeling of substituted phenol toxicity. The best models derived show a certain contribution of the electronic factor in addition to the hydrophobicity factor; while the phenol geometric properties were found to be insignificant. The superdelocalizability indices characterizing the electron acceptor properties of the oxygen and its neighbouring carbon atom were found to be of importance along with the phenol acidity used in previous models and they can replace the latter in calculating substituted phenol toxicities. The complicated mechanism of the toxic agent‐receptor interaction is thus supposed to include some charge transfer from the biosubstrate to these two phenolic atoms with possible formation of a covalent or a hydrogen bond, although the charge‐controlled reactions seem to prevail.