QSPR to aqueous solubility (lg Sw) of alkyl(1-phenylsulfonyl) cycloalkane-carboxylates using MLSER model and ab initio

Based on the modified linear solvation energy relationship (MLSER) model and quantum chemical descriptors computed at HF/STO-3G, HF/LANL2DZ, B3LYP/LANL2D and B3LYP/6-31G* levels, different quantitative structure–property relationships (QSPRs) to the aqueous solubility (lg Sw) of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxylates were obtained. It is suggested that the eight models developed in the present study all have good correlation and relatively small error, in which the model with four variables, the most positive formal charge (qH+), molecular volume (Vi), melting point (mp) and free energy (G0) as descriptors obtained from B3LYP/6-31G* level, exhibited the best optimum correlation (r2 = 0.9743 and q2 = 0.9644, respectively) and smallest error, and thus are advantageous to other models. It was also found that molecular volume is the most significant factor influencing lg Sw. The lg Sw increased with increasing qH+ and G0, while decreased with increasing Vi and mp. The MLSER model achieved from ab initio calculation is better than that from the semiempirical AM1 method.