title: Quantitative structure-activity relationships. 1. The modified Free-Wilson approach.
abstract: The relationships between the linear free energy related Hansch model and the mathematical models of Free-Wilson and Bocek-Kopecký are reviewed and discuss. Some examples are given to illustrate the theoretically derived relationships and to demonstrate scope and limitations of each mathematical model. The modified Free-Wilson approach is shown to be completely equivalent to a nonparabolic Hansch approach; it can be used to study additivity or nonadditivity of group contributions and to control and improve the fitting of Hansch equations. The Bocek-Kopecký approach is related to the parabolic form of the Hansch approach; its practial use is limited by the great number of variables involved.
mesh_terms: D000818:Animals; D000935:Antifungal Agents; D002800:Cholinesterase Inhibitors; D004837:Epinephrine / Q000037:antagonists & inhibitors; D005990:Glycerol / Q000494:pharmacology; D006993:Hypnotics and Sedatives; D007700:Kinetics; D008956:Models, Chemical; D010627:Phenethylamines / Q000494:pharmacology; D010647:Phenyl Ethers / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D011409:Propylene Glycols / Q000494:pharmacology; D012044:Regression Analysis; D013329:Structure-Activity Relationship; D013974:Thyroxine / Q000031:analogs & derivatives; D014508:Urea / Q000031:analogs & derivatives
chemical_list: D000935:Antifungal Agents; D002800:Cholinesterase Inhibitors; D006993:Hypnotics and Sedatives; D010627:Phenethylamines; D010647:Phenyl Ethers; D010880:Piperidines; D011409:Propylene Glycols; D014508:Urea; D005990:Glycerol; D013974:Thyroxine; D004837:Epinephrine