Ligand mechanism

Wolfe, Jr., S.A., De Souza, E.B., 1992. Sigma receptors in the brain-en-docrine-immune axis. In Kamenka, J.M., Domino, E.F. (Eds.), Multiple Sigma and PCP Receptor Ligands Mechanisms for Neuromodulation and Neuroprotection , NPP Books, Ann Arbor, pp. 927-958. 

Mechanism (1) was excluded because the rate remains unaffected when the reaction is conducted under high CO pressure and the AS values are much lower than is typical for reactions that are initiated by CO loss (see the section on Substitution of CO by phosphines). Mechanism (2) was excluded based on the rather small solvent dependence. Mechanism (3) was rejected because neither radical initiators nor radical scavengers have any influence on the reaction, and there is no correlation between AH and the homolytic C-X bond energies. Intramolecular attack by X on one of the CO ligands (mechanism 4) is conceivable when X contains lone pairs (Cl, Br, SePh and TePh) but not with X = SnPh3 or PbPh3 and was also excluded. 

EC50 = 2.9 pM. To further structurally characterize the ligands mechanism of action, induced fit docking [51] was performed, showing evidence that five active flavonoids induce conformational change in the receptor upon binding. 

These data further suggest a reason for the different efficacy of PtRu catalysts in reformate vs. methanol. Since the BF mechanism operates at lower anode potential than the direct ligand mechanisms, more homogeneously alloyed PtRu catalysts with smaller Ru islands should be more effective in reformate and less well-mixed alloys (with large Ru islands) better in methanol fed... 

CO oxidation can occur via the bifunctional mechanism, the ligand mechanism, or via a hydrogen replacement mechanism, and the morphology and island type strongly determines which of these is more important. 

Renfrew AK (2014) Transition metal complexes with bioactive ligands mechanisms for selective ligand release and applications for drug delivery. Metallomics 6 1324—1335... 

Figure 19.2 The tethered ligand mechanism of thrombin receptor activation. Thrombin binds to the extracellular domain of the receptor and cleaves it at Arg -Ser. The newly generated serine N-terminus binds intramolecularly to the receptor, triggering cellular activation.

The specific role of the electrolyte composition at a given pH is an extremely common experience. The contribution of anions other than hydroxyl is expected through the acid-catalyzed or anion-ligand mechanism [24,25]. It must be emphasized that the role of pH in polyacids, such as H2SO4, may be obscured by the correlated changes of electrolyte composition depending on acidity constants [86],... 

Specific anion dependence is expected to occur in the passive andtianspassive domains, and dissolution in the active range can be made to deviate from the hydroxo-ligand mechanism [87] only by anions able to replace OH, essentially SH" [88] and the halide ions. In the case of iron, due to the well-known passivity breakdown and subsequent localized corrosion by halide ions and particularly Cl , chloride effects have been investigated extensively. Complexing anions such as acetate have also been considered to a lesser extent. 

Complexes of acac and Related Ligands.—Mechanisms of isomerization of -diketone complexes have been the subject of a review. Two studies of isomerization and racemization rates of diketone complexes establish orders of relative reactivity for complexes of various cations. For complexes M(tfac)a, rates of isomerization are in the following order ... 

---