Gel Phase Description applied to certain solid supports which display properties intermediate between solid and liquid phases, e.g. in the apparent mobility of the support as determined by nuclear magnetic resonance (NMR) spectroscopy.
Generic Structure The general structural formula of a library, consisting of the scaffold plus an indication of the position of attachment of the various residues.
Genetic Algorithm Method for library design by evaluating the fit of a parent library to some desired property (e.g. the level of activity in a biological assay or the computationally determined diversity of the compound set) as measured by a fitness function. The design of more optimal daughter libraries is then carried out by a heuristic process with similarities to genetic selection in that it employs replication, mutation, deletions, etc. over a number of generations.
GPCR G - protein coupled receptors form a large super - family of proteins composed of three major classes and more than 30 subfamilies. They are integral membrane proteins characterized by seven membrane- spanning (transmembrane; TM) regions. They are involved with signal transduction across cell membranes. Many medically and pharmacologically important proteins are included in this super-family: e.g., Acetylcholine receptors, Dopamine receptors, and Opioid receptors.
Hard Drug A nonmetabolizable compound, characterized either by high lipid solubility and accumulation in adipose tissues and organelles, or by high water solubility. In the lay press the term refers to a powerful drug of abuse such as cocaine or heroin.
High-Throughput Screening Process for rapid assessment of the activity of samples from a combinatorial library or other compound collection, often by running parallel assays in plates of 96 or more wells. A screening rate of 100 000 assays per day has been termed "Ultra High-Throughput Screening" (UHTS).
Hit Library component whose activity exceeds a predefined, statistically relevant threshold.
Hit Explosion Process of establishing structure-activity relationships around a hit by preparing new libraries or series of analogues using related building blocks and/or scaffolds to those employed in the preparation of that hit.
In Situ Scaffold Formation Process whereby a scaffold is formed during library production which contains residues of at least two building blocks.
Inhibitors Agents that block or suppress the activity of enzymes such as proteases.
Ion Channel An integral membrane protein that provides for the regulated transport of a specific ions across a membrane.
Isosteres Molecules or ions of similar size containing the same number of atoms and valence electrons.
IR Thermography Infrared thermography Screening technique where the heat of reaction of a multitude of samples is simultaneously measured. Has been applied in particular to the screening of libraries of potential catalysts.
Iterative Deconvolution Multistep application of deconvolution where successively smaller sublibraries are prepared and tested to identify individual active members of a combinatorial library.