628317-02-2Relevant articles and documents
Chloroperoxidase and hydrogen peroxide: An efficient system for enzymatic enantioselective sulfoxidations
Colonna,Gaggero,Casella,Carrea,Pasta
, p. 95 - 106 (1992)
High enantioselectivities were obtained in chloroperoxidase catalyzed oxidation of organic sulfides (99% ee in the case of methyl 2-pyridyl sulfide) with H2O2 in aqueous buffer solution, pH 5, at 25°C. The kinetic parameters in the oxidation of a series of sulfides both with H2O2 and tert-butyl hydroperoxide were determined and the data are consistent with enzymatic oxidation involving presumably a ternary complex. In all cases the reaction afforded the (R) sulfoxide as predominant or exclusive enantiomer.
Binding of hydrophobic hydroxamic acids enhances peroxidase's stereoselectivity in nonaqueous sulfoxidations
Das, Prasanta Kumar,Caaveiro, Jose M.M.,Luque, Susana,Klibanov, Alexander M.
, p. 782 - 787 (2007/10/03)
Horseradish peroxidase exhibits a meager stereoselectivity (E) in the sulfoxidation of thioanisole (1a) in 99.8% (v/v) methanol. The E value, however, is greatly enhanced when the enzyme forms a complex with benzohydroxamic acid (2a). These findings are rationalized by means of molecular dynamics simulations and energy minimization which correctly explain (i) why the free enzyme is not stereoselective, (ii) why 2a inhibits peroxidase-catalyzed sulfoxidation of 1a but the enzymatic formation of one enantiomer of the sulfoxide product is inhibited much more than that of the other, thereby raising peroxidase's E, and (iii) why in the presence of 2a the enzyme favors production of the S sulfoxide of 1a. The generality of the observed ligand-induced stereoselectivity enhancement is demonstrated with other hydrophobic hydroxamic acids, as well as with additional thioether substrates.
