Electronic complementarity

The key and lock mechanism is widely accepted as a principle of molecular recognition. This concept is based on steric and electronic complementarity between... 

Unsubstituted NDIs are seen as attractive chromophoric units because of their electronic complementarity to ubiquinones and their ease of formation from commercially available starting materials, forming symmetrical and asymmetric analogues relatively efficiently. Simple aromatic diimides undergo single reversible reduction processes either chemically or electrochemically to yield the corresponding radical anion in high yield (E1 = -1.10V vs. Fc/Fc+) (Fc ferrocene) [20a]. 

Ionic or molecular recognition by a host molecule will depend upon the degree of structural and electronic complementarity between host and guest. Structural... 

The first category of modifications involved substitutions at C5 of the pyrimidine nucleobase (Figures 14 and 15) [47]. It is well known that C5 substitutions control the pAa of the N3 of C in nucleosides and drastically alter the hydrophobic driving force, base stacking and electronic complementarity... 

The substrate can bind to the enzyme at the active site via noncovalent interactions (van der Waals, electrostatic, hydrogen bonding, hydrophobic), and with a specific geometric complementarity, as the surface of the active site of that enzyme is complementary in shape to the substrate. Electronic complementarities are due to the fact that the amino acid residues at the active site are arranged to interact specifically with the substrate. Although most enzymes are amino acids with hundreds of acids in the chain, the active site is the size of the substrate. Complementarity in the structure and charge between the enzyme and the substrate is illustrated by the so-called lock-and-key concept (Figure 2.15). 

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