Synthetic Organic Ligands Structure and Conformation

Depending on the substituents present, macrocyclic systems may exist in different conformations. However, a number of regularities may be found, which especially distinguish rings with even and odd number of bonds 98). In the present case, although the conformations of the free and complexed ligand may be different, both are of importance. 

In principle, the closer the equilibrium conformation of the free ligand is to its conformation in the complex, the smaller is the destabilization introduced by ligand deformation on complexation. 

Ligand type Compounds Cavity Diameter (A) Number of Binding Sites Ref. 

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