Using AM1 hamiltonian in quantitative structure‐activity relationship studies of phenylthio‐carboxylates

AM1 Hamiltonian contained in the MOPAC(6.0) program package was used to compute descriptors for eighteen phenylthio‐carboxylates. The Modified TLSER (MTLSER) model was used to develop a QSAR equation for toxicity of these compounds. The obtained equation can be used to predict toxicity to Photobacterium Phosphoreum of this series of compounds. The polarizability (α) increases the toxicity. The dipole moment (μ) and the most positive net atomic charge on a hydrogen atom (qH+) decrease the toxicity. The study showed the advantages of the MTLSER descriptors: they permit near a priori prediction of toxicity; they can be easily and precisely obtained by computation instead of experiment, thus a large amount of expenses and time can be saved; and they have clear physicochemical interpretations, and interpretation of the correlation equations can suggest modes of interaction between toxicants and organisms.