Pharmacokinetics refers to the study of absorption, distribution, metabolism and excretion (ADME) of bioactive compounds in a higher organism. (See alsoDrug disposition).
Pharmacophore (pharmacophoric pattern)A pharmacophore is the ensemble of steric and electronic features that is necessary to ensure the optimal supramolecular interactions with a specific biological target structure and to trigger (or to block) its biological response.
A pharmacophore does not represent a real molecule or a real association of functional groups, but a purely abstract concept that accounts for the common molecular interaction capacities of a group of compounds towards their target structure. The pharmacophore can be considered as the largest common denominator shared by a set of active molecules. This definition discards a misuse often found in the medicinal chemistry literature which consists of naming as pharmacophores simple chemical functionalities such as guanidines, sulfonamides or dihydroimidazoles (formerly imidazolines), or typical structural skeletons such as flavones, phenothiazines, prostaglandins or steroids.
Pharmacophoric descriptorsPharmacophoric descriptors are used to define a pharmacophore, including H-bonding, hydrophobic and electrostatic interaction sites, defined by atoms, ring centers and virtual points.
PlaceboA placebo is an inert substance or dosage form which is identical in appearance, flavor and odour to the active substance or dosage form. It is used as a negative control in a bioassay or in a clinical study.
PotencyPotency is the dose of drug required to produce a specific effect of given intensity as compared to a standard reference.
Potency is a comparative rather than an absolute expression of drug activity. Drug potency depends on both affinity and efficacy. Thus, two agonists can be equipotent, but have different intrinsic efficacies with compensating differences in affinity.
ProdrugA prodrug is any compound that undergoes biotransformation before exhibiting its pharmacological effects. Prodrugs can thus be viewed as drugs containing specialized non-toxic protective groups used in a transient manner to alter or to eliminate undesirable properties in the parent molecule . (See also Double prodrug).
QSARSee Quantitative Structure-Activity Relationships.
Quantitative Structure-Activity Relationships (QSAR)Quantitative structure-activity relationships are mathematical relationships linking chemical structure and pharmacological activity in a quantitative manner for a series of compounds. Methods which can be used in QSAR include various regression and pattern recognition techniques.
ReceptorA receptor is a molecule or a polymeric structure in or on a cell that specifically recognizes and binds a compound acting as a molecular messenger (neurotransmitter, hormone, lymphokine, lectin, drug, etc.).
Receptor mappingReceptor mapping is the technique used to describe the geometric and/or electronic features of a binding site when insufficient structural data for this receptor or enzyme are available. Generally the active site cavity is defined by comparing the superposition of active to that of inactive molecules.
Second messengerA second messenger is an intracellular metabolite or ion increasing or decreasing as a response to the stimulation of receptors by agonists, considered as the "first messenger". This generic term usually does not prejudge the rank order of intracellular biochemical events.
Site-specific deliverySite-specific delivery is an approach to target a drug to a specific tissue, using prodrugs or antibody recognition systems.
Soft drugA soft drug is a compound that is degraded in vivo to predictable non-toxic and inactive metabolites, after having achieved its therapeutic role.
SPCSee Structure-property correlations.
Structure-activity relationship (SAR)Structure-activity relationship is the relationship between chemical structure and pharmacological activity for a series of compounds.
Structure-based designStructure-based design is a drug design strategy based on the 3D structure of the target obtained by X-ray or NMR.
Structure-property correlations (SPC)Structure-property correlations refers to all statistical mathematical methods used to correlate any structural property to any other property (intrinsic, chemical or biological), using statistical regression and pattern recognition techniques.
SystemicSystemic means relating to or affecting the whole body.
TeratogenA teratogen is a substance that produces a malformation in a foetus.
Three-dimensional Quantitative Structure-Activity Relationship (3D-QSAR)
A three-dimensional quantitative structure-activity relationship is the analysis of the quantitative relationship between the biological activity of a set of compounds and their spatial properties using statistical methods.
Topliss treeA Topliss tree is an operational scheme for analog design.
Transition-state analogA transition-state analog is a compound that mimics the transition state of a substrate bound to an enzyme.
XenobioticA xenobiotic is a compound foreign to an organism (xenos [greek] = foreign).
Return to home page for Glossary of Terms Used in Medicinal Chemistry .