QSAR study on pKa vis-Ã -vis physiological activity of sulfonamides: a dominating role of surface tension (inverse steric parameter)

The present study describe the dominating role of surface tension (ST) on the modeling, monitoring, and estimating pKa for a large series of 43 substituted sulfonamides. Because of direct correlation of ST with parachor (Pc) vis-à-vis molecular volume (MV), ST is considered as a steric parameter. Single as well as multi-parametric regressions have indicated that ST has a dominating role in QSAR of the set of sulfonamides used and that excellent results are obtained in multi-parametric regression analysis. The results are discussed critically on the basis of statistics.