Structure-activity relationship . See

Since we are interested in evaluating structure-activity relationships (see Sect. 2.2), it is important to combine several analytical methods to allow a characterization at a molecular level for example, elemental analysis, IR, and advanced NMR spectroscopies, EXAFS and chemical reactivity studies. 

The precursors given above vary in potency, but are versatile with the ability to be used in place of one or the other and still produce an active compound. Yields may suffer somewhat from this interchanging of precursors, but if an equimolar amount is used this should be minimal. When researching THCs, remember that there are different methods of numbering the molecule and this will depend on who has written the material that you are reading. For a brief report on structure activity relationships see JMC, 16, 1200 (1973) and also Chemical Revues, 76, 75 (1976). 

Apart from a few notable exceptions (see later), all known narcotic antagonists are based on the morphine, morphinan, or benzomorphan polycyclic systems, that is, on three closely related groups of opioid ligands that share many structure-activity relationships (see Chapters 2, 3, and 4). Details of antagonist representatives of each group will now be given, chiefly confined to N- allyl and N-cyclopropylmethy 1 (CPM) derivatives, with minimal chemical details. 

Quantitative Structure-Activity Relationship See Toxicity Testing, Modeling. 

T. causes diseases in plants by inhibition of protein and nucleic acid synthesis, e.g., leaf rot and brown spot disease in rice and tobacco. T. has antiviral and insecticidal activities and inhibits the growth of mammalian cell cultures. T. can occur in moldy tomatoes and apples as well as products produced therefrom. For structure activity relationships, see Lit.. ... 

Similar concepts are important in medicinal chemistry, in which the properties of a proposed drug are predicted on the basis of the effects of a series of known drugs. A leading researcher in this area is Corwin Hansch, for whom the Hansch correlation is named. For a discussion of quantitative structure—activity relationships, see Hansch, C. Leo, A. Exploring QSAR Fundamentals and Applications in Chemistry and Biology American Chemical Society Washington, DC, 1995. 

Figures highlighted in bold indicate inhibition percentages considered to be clear, unequivocal, and significant in interpreting antibody combining site structure—activity relationships. See also Fig. 6.16)...

Quantum chemistry thus has several important functions in CALD to optimize structures (find low-energy conformations), to determine force field parameters (see next section), and to compute molecular descriptors for use in quantitative structure-activity relationships (see Section 5.6). 

An ambitious attempt to explain the structure-activity relationships (see QSAR) of opioid agonists and antagonists... 

For a detailed discussion on these structure-activity relationships, see Fukuzawa et al, 1997. 

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