The molecular topological research on acute toxicities of substituted arenes to aquatic organisms

A novel topological index (¹D) based on the adjacency matrix and atomic characteristic values (d_i, which is equal to (n_i–1)²m_i–h_i) was derived in this paper. The index ^lD was defined as ^lD=Σ(d_i·d_j)^0.5. The linear regression equations of ^lD, lgK_ow and acute toxicities for substituted arenes to aquatic organisms were proposed as follows: -lgEC₅₀=2.391+0.025¹D+0.238lgK_ow; -lgLC₅₀ = 2.192 + 0.021 ¹D +0.414lgK_ow. The correlation coefficients (R²) and the leave-one-out (LOO) cross validation R_cv² for the EC₅₀ and LC₅₀ models were 0.881 and 0.852, 0.939 and 0.916, respectively. The QSAR models have favorable correlation, as well as robustness and good prediction capability by R_cv², V_IF tests. These results were better than those reported in the literatures.