Ligand fitting

This indicates how well the ligand fits in the binding site. 

Figure 9.13. A ligand fits better the site on H, so that the H-form is stabilized in the absence of water. In the presence of water, the possibility of formation of a HB bridge will stabilize the L-form.

FIGURE 4.9 Molecular models of the nine potent lead variants derived by similarity analysis of the Analog 5-1-9-3-4, generated by the ligand fit docking algorithm of Cerius2 [20]. 

When [SmCp 3] was eventually isolated, it was found to be [Sm() -C5Me5)3] (Eig-ure 6.10) and also that three of these bulky ligands fit round samarium with an increase in bond length from the usual 2.75 A to 2.82 A. 

A receptor is a part of a large molecule (often a protein) or structure which binds another, usually smaller, molecule. This binding site will be specific for a particular chemical or group of chemicals, normally hormones or transmitters, and the binding may be very tight. The receptor is like a lock into which the chemical substance (the ligand) fits as a key. So receptors are similar to enzymes. 

Almost simultaneously nickel (0) compounds with PCI3 (107, 303), PF3 (53), and PR3 (160) were obtained as well. These ligands fit the classifications reported for the low electronegativity, which could be qualitatively deduced from their basicity, but they were not isostructural... 

Some of these ligands fit into more than one category. For example. I not only has filled p orbitals to donate electrons but also has low-lying empty d orbitals to accept electrons. R3P, as shown, may accept tt electron donation into its empty d or P—R rr orbitals the [Pg.745]

Figure 6.25 Effect of side group size on ligand fit into imprinted site.

---