Cytochrome P450 mimics

Fig. 7 Cytochrome P450-mimic oxidation of fenvalerate (9) by iron(ffl) porphyrin. The values in parentheses are percent of the applied 14C (Asterisk labeled position) after 50 min...

Figure 6.8 Schematic representation of a cytochrome P450 mimic in which catalytic manganese porphyrins are captured in the bilayer of polymerized vesicles. Colloidal platinum encapsulated in the vesicles in combination with molecular hydrogen serves as a reductant.

Figure 6.9 (a) Components of self-assembled cytochrome P450 mimics, (b) Schematic representation of such a mimic. 

In nature many enzymes are embedded in membranes, which not only serve as a scaffold but also regulate the transport of substrates and products, and control the concentrations of protons and other ions. Instead of embedding molecular catalysts into artificial membranes, as was done for the cytochrome P450 mimic, it is also possible to make amphiphiles that constitute the membranes catalytic themselves. 

Attempts by chemists to develop enzyme mimics have ranged from the use of dendrimers ( dendrizymes, reviewed by Brunner, 1995) to metal-templated superoxide dismutatese (SOD) mimics (reviewed in Riley, 1999, 2000) to supramolecular cytochrome P450 mimics. The role of cytochrome P450 in biology is diverse. A known... 

M.C. Feiters, A.E. Rowan and R.J.M. Nolte (2000) Chemical Society Reviews, vol. 29, p. 375 - From simple to supramole-cular cytochrome P450 mimics . 

More recently Tabushi et have used oxygenated Fe (TpivPP)Cl in the presence of HCl and H2-colloidal platinum supported on poly(vinylpyrrolidone) in the presence of acid chlorides as a cytochrome P450 mimic. Under such conditions cyclohexene is converted to its epoxide and slow reduction of the ferric complex followed by formation of the dioxygen ferrous complex completes the catalytic cycle. 

Figure 19 Schematic representation of the cytochrome P450 mimic and the redox couples and components. (Reproduced from Ref. 60. American Chemical Society, 1995.)...

Figure 3 Catalytic oxidation by a cytochrome p450 mimic." Cyclodextrins provide hydrophobic binding sites while the metal centre oxidises nearby unactivated carbons.

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