Factors Affecting the Drug-Receptors Interaction

FACTORS AFFECTING THE DRUG-RECEPTOR INTERACTION

Isosterism: Groups of atoms that possess similar physical or chemical properties of a molecule due to similarity in size, electronegativity, or stereochemistry are referred to as isosteres. The existences of such groups in molecules are termed isosterism. For example, N2 and CO, both have 14 total electrons and no charges and show same physical properties. In sulphonamides, the replacement of atoms or groups with various isosters, other analogues are developed. Potency of these agents varied according their interaction with the target.

Steric features of a drug: The drug must possess stereoselective property to initiate a response at a particular receptor. For example, trans-diethylstilbosterol is oestrogenic while cis-isomer is almost inactive.

Optical isomerism: Enantiomers, asymmetry, and chirality are important concepts to give better receptor interaction with drugs. Although each enantiomer has some physical and chemical properties, they may act in different ways and in different sites to produce variable pharmacological action.