DFT studies of the toxicity of 4-substituted 1,2-benzoquinones

Abstract

Toxicity descriptors based on Cu(II) coordination ability of 4-substituted 1,2-benzoquinones and subsequent O → Cu electron density transfer are introduced. Geometries of quinones and of their Cu(II) complexes are optimized using DFT treatment. The transferred electron density is evaluated using the copper charge or the Laplacian of electron density at the Cu–O bond critical points. The toxicity of quinones with electron-withdrawing substituents is much more sensitive to the extent of electron density transfer. Quinone O atoms exhibit equal trends for electron-donating substituents only.