Quantitative structure-activity relationships have been developed for three series of phenolic substrates viz. phenols, hydroxyindoles and tyramines in microsomal hydroxylation. The Fujita-Ban group contributions of various substituents have been calculated. Mono-, bi-and tri-substituted phenols have been investigated in the light of the linear free energy related model also.

The article reviews in brief, thede novo group additivity approach and, at length, the different topological approaches to obtain predictive and internally consistent correlations between various properties and structural features of molecules. The stress has mainly been on the molecular connectivity method. A new rational scheme for nomenclature of connectivity indices of different orders and types is introduced. The concept of the perturbation connectivity parameter developed by us recently has been applied to obtain correlations for molar refraction, boiling point, molar volume, heat of atomisation, heat of combustion, heat of vaporisation, magnetic susceptibility and critical constants of alkanes, alcohols and alkylbenzenes. A comparative study of various approaches reveals that the present perturbation topological approach has an edge over other similar methods.