Structure-toxicity relationship for aliphatic compounds using quantum topological descriptors

Quantitative structure-activity relationships were developed to predict the toxicological properties for various classes of aliphatic compounds on Tetrahymena pyriformis. On the basis of properties extracted from calculated wave functions we are able to reproduce the experimental sequence of toxicity for a data set of 88 aliphatic molecules. These properties have been evaluated at the bond critical points (BCP). We found that it is possible to relax common skeleton requirement in developing QSAR and compare BCP properties for very different molecular fragments. Thus, the properties derived from the topological analysis of the electron density have been used to model the toxicity data for different classes of aliphatic compounds. The final models were chosen on the basis of the squared correlation coefficients (R2), leave-one-out cross-validated regression coefficients (RCV2) and the coefficient of determination adjusted for the degree of freedom (Radj2). The obtained models can reproduce about 97% of variances in toxicity prediction for different class of aliphatic compounds.