QSPR models of boiling point, octanol-water partition coefficient and retention time index of polycyclic aromatic hydrocarbons

A Quantitative Structure-Property Relationship (QSPR) analysis and study of polycyclic aromatic hydrocarbons (PAHs) is presented. Three physicochemical properties related to their environmental impact are studied: boiling point (bp), octanol-water partition coefficient (log K-ow) and retention time index (RI) for reversed-phase liquid chromatography analysis. The geometry of all PAHs were optimized by the semi-empirical method AMI and used to calculate thermodynamic, electronic, steric and topological descriptors: HOMO and LUMO energies and the GAP between them, molecular hardness, polarizability, atomic charges, connectivity index, volume and surface area among others. After variable selection, principal component regression (PCR) and partial least squares (PLS) with leave-one-out crossvalidation were used for building the regression models. The regression coefficients obtained for the models were 0.995 (PCR and PLS) for bp, 0.975 (PCR) and 0.976 (PLS) for log K-ow, and 0.898 (PCR and PLS) for RI. Finally, the models were used to predict these properties for those compounds for which experimental measurements are still unknown. (C) 2003 Elsevier B.V. All rights reserved.6634169910912