Ligand association

PPAR isotype Tissues of highest expression Primary physiological effects Endogenous ligands Synthetic ligands Associated disease state/ indication... 

An understanding of these LR dynamics requires both biological and mathematical insight. In this chapter we define these biological processes in terms of RG mechanisms and consider whether these processes reflect receptor in different states of activity. Next we develop a mathematical description to account for at least six separate processes (1) ligand association, (2) rapid ligand dissociation, (3) slower dissociation, (4) internalization, and (5 and 6) two different Interconversions among receptor forms. 

In principle, the calculation of concentrations of species of a complexation equilibrium is no different from any other calculation involving equilibrium constant expressions. In practice, we have to consider multiple equilibria whenever a complex is present. This is because each ligand associates with the complex in a separate process with its own equilibrium expression. For instance, the silver-ammonia equilibrium is composed of two steps ... 

Au-C bonds, mixed metal gold-silver dimers of planar, trinuclear complexes are readily formed by mixing gold(I) carbeniates and gold(I) benzylimidazolates with silver(I) pyrazolates in stoichiometric ratios. The complexes retain the ligands associated with the metal atoms of the starting materials. 

Novotny M., Ma W., Wiesler D. and Zidek L. (1999). Positive identification of the puberty-accelerating pheromone of the house mouse the volatile ligands associating with the major urinary protein. Proc Roy Soc Lond (B) 266, 2017-2022. 

Robertson D., Benyon R.L. and Evershed R. (1993). Extraction, characterization and binding analysis of two pheromonally active ligands associated with major urinary proteins of house mouse (Mus musculus). J Chem Ecol 19, 1405-1416. 

Figure 11 Scheme 3 — ligand-associated nucleophilic reaction. 

Fluorescence measurements are carried out in 50 mM Hepes/KOH (pH 7.2), 100 mMKCl, 0.5 mMEDTA, and 2 mMDTT at 20°. To 0.1 or 0.05 /iM mouse eIF4E(28-217) (i.e., the first 27 amino acid residues are truncated) (Niedzwiecka et al., 2002) are added solutions of increasing cap analog concentrations. For this protein—ligand association, an excitation wavelength of 280 nm and an emission wavelength of 337 nm are used. 

C bonds using Rh(PPh3)3Cl. Step 1, step 3, ligand association step 4,... 

Scheme 8.4 Catalytic cycle for the hydroformylation of C=C bonds using HRh(CO)2(PPh3)2. Step 1, ligand dissociation step 2, ligand association step 3, /J-hydride transfer step 4, ligand dissociation step 5, CO insertion step 6, oxidative addition of H2 steP 2, reductive elimination step 8, ligand association...

Nickel-catalyzed electroreductive cleavage of the carbon-oxygen bond of allyl ethers has been reported [356], The influence of the nature of the ligands associated to the Ni center tends to determine the chemoselectivity of the above reaction [357]. 

These reactions can also be conducted in an undivided cell, as shown in the case of aryl halides bearing an unsaturated chain (Table 7, entry 7b). Cyclam and other tetradentate donor ligands associated with nickel were used, magnesium being the most convenient anode in these reactions [75-77]. 

Diynes have already been used for building polycylic compounds in the presence of CO2 and a stoichiometric amount of Ni(0) bicyclic pyrones were obtained [117]. With the electrocarboxylation method, linear or cyclic mono-carboxylic acids were obtained as main products from non-conjugated diynes depending on the ligand associated to Ni [118, 119]. Thus ring-fomation occurred with the Ni-bipyridine complex at normal pressure of CO2 on the other hand, in the presence of PMDTA as ligand and with a 5 atmosphere pressure of CO2, linear adducts were mainly formed as illustrated in Eq. (16) ... 

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