PARAMETRIZATION OF THE ORIENTATIONAL EFFECTS IN THE DRUG-RECEPTOR INTERACTION INTERACTION

Abstract

We present a physically based treatment of the molecular rotational partition function for the case of the interaction of a macromolecular receptor with a small biologically active molecule. This leads to the proposal of a new substituent para meter that we call the Orientational Para meter. Its physical interpretation is that it gives an account of the substituent's influence on the percentage of molecules achieving the correct orientation to interact with the receptor. Finally we propose a universal way to calculate its values, avoiding the need of building long tables. A comparison between the old and new ways to calculate it is presented. We provide here an example to show its usefulness in QSAR studies