Medicinal Chemistry Glossary

Absorption, Distribution, Metabolism, Excretion, and Toxicity — the key pharmacokinetic and safety parameters evaluated during drug development.

The fraction of an administered drug dose that reaches systemic circulation in its active form.

A chemical substituent or group with similar physical, chemical, or biological properties that can replace another in a drug molecule.

A property of molecules that are non-superimposable on their mirror images, resulting in enantiomers with potentially different biological activities.

The rapid synthesis of large numbers of structurally related compounds for screening against biological targets.

A superfamily of heme-containing enzymes in the liver responsible for the oxidative metabolism of the majority of therapeutic drugs.

A change in a drug's effect caused by the co-administration of another drug, often through competition for metabolic enzymes or transporters.

The concentration of a drug that produces 50% of the maximum possible effect, used as a measure of potency for agonists.

One of a pair of molecules that are mirror images of each other but cannot be superimposed, often having different biological activities.

The initial metabolism of an orally administered drug by the liver and intestinal wall before it reaches systemic circulation.

The time required for the plasma concentration of a drug to decrease by 50%, determining dosing frequency.

An automated method for rapidly testing large numbers of compounds for activity against a biological target.

The concentration of an inhibitor that reduces the activity of its target by 50%, a standard measure of inhibitory potency.

A chemical compound with demonstrated activity against a target that serves as the starting point for optimization into a drug candidate.

A compound's affinity for lipid environments relative to aqueous environments, quantified by logP or logD.

The logarithm of the partition coefficient between octanol and water, measuring a compound's lipophilicity.

A computational technique predicting the binding pose and affinity of a small molecule in a protein's binding site.

The study of the biochemical and physiological effects of drugs on the body and their mechanisms of action.

The study of how the body absorbs, distributes, metabolizes, and excretes a drug over time.

The three-dimensional arrangement of chemical features essential for a molecule's interaction with a specific biological target.

An inactive compound that is metabolically converted to an active drug in vivo to improve absorption, distribution, or tolerability.

Quantitative Structure-Activity Relationship — mathematical models relating molecular descriptors to biological activity for activity prediction.

The ability of a drug to preferentially act on its intended target over other biological targets, minimizing off-target effects.

The relationship between a molecule's chemical structure and its biological activity, used to guide medicinal chemistry optimization.

The ratio of the dose producing toxic effects to the dose producing therapeutic effects, indicating a drug's margin of safety.