USE OF TOPOSTRUCTURAL, TOPOCHEMICAL, AND GEOMETRIC PARAMETERS IN THE PREDICTION OF VAPOR-PRESSURE - A HIERARCHICAL QSAR APPROACH

Numerous quantitative structure-activity relationships (QSARs) have be en developed using topostructural, topochemical, and geometrical molec ular descriptors. However, few systematic studies have been carried ou t on the relative effectiveness of these three classes of parameters i n predicting properties. We have carried out a systematic analysis of the relative utility of the three types of structural descriptors in d eveloping QSAR models for predicting vapor pressure at STP for a set o f 476 diverse chemicals. The hierarchical technique has proven to be u seful in illuminating the relationships of different types of molecula r description information to physicochemical property and is a useful tool for limiting the number of independent variables in linear regres sion modeling to avoid the problems of chance correlations.