Biological testing, chemical class

The area of nonsteroidal antiestrogens along with other classes of nonsteroidal antagonists of sex-steroid hormone action has been reviewed to 1986, and these compounds have been grouped by chemical stmcture as a basis of classification rather than any biochemical or biological test system utilized to assess antagonist activity (46). 

In the context of general screening, computational library design involves the selection of a subset of compounds that are optimally diverse and representative of available classes of compounds, leading to a non-redundant chemical library for biological testing. Methods reported in the literature include... 

Like other medications also, psychopharmaceuticals can be classified according to various principles the chemist characterizes them by their chemical structure, the pharmacologist by their actions in representative biological test systems and the doctor by their therapeutic uses or indications. The classification according to clinical criteria today covers the following classes of psychopharmaceuticals ... 

More detailed aspects of hydrocarbon bouquets acting as pheromones and various problematic aspects in revealing their true biological function have been discussed.2, 29° In many cases, however, only extracts of the insect cuticle are used for bioassays, sometimes roughly separated by chromatography into different chemical classes. Tests with synthetic blends have been less frequently performed only such approaches would allow unequivocal assignment of activity to the compounds tested. Actually, in whole extracts or fractions thereof... 

Chemical Class Fractionation of Fossil-Derived Materials for Biological Testing... 

Selection of substituents from a certain chemical class may not really test the inllucncc of a parameter on biological activity. There is little numerical difference among the /Vm ur values for the four aliphatic groups or the four halo-... 

In many chemical and pharmaceutical companies and institutions huge amounts of biological test data have been stored in computer-readable form but evaluated only rather superficially for active drugs and compound classes. These data cemeteries could be examined far more systematically and thoroughly with the assistance of computer methods. 

Biological effects, e.g., mutagenicity in a short-term test, of a crude material (or a crude extract or leachate) may be difficult to detect because of overall toxicity of the mixture or the very low concentrations of the active components, or both. Therefore, it is desirable to subdivide the materials into fractions that can be tested much more accurately and that lend themselves to chemical analyses for identification of the active compounds much more readily than does the starting test material. Possible disadvantages include the loss or modification of specific components or the loss of potential for synergistic effects. Various approaches to fractionation by chemical class are discussed in the following sections. 

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