Nitric oxide synthase-like activity of ion exchange resins modified with iron (III) porphyrins in the oxidation of l-arginine by H2O2: Mechanistic insights

Resin supported iron (III) porphyrins, prepared by strong electrostatic interactions between the ionic iron (III) porphyrins and counter ionic groups on the surface of the support, were found to be very efficient catalysts for H2O2 mediated oxidation of l-arginine with the formation of citrulline and nitric oxide, and the yields of these products were remarkably higher than those obtained with corresponding soluble iron (III) porphyrins. No leaching of iron porphyrin or uncomplexed iron ions was observed. A high-valent iron–oxo porphyrin complex was suggested as a reactive intermediate for this oxidation reaction.