Regiospecificity in oxidative heme modification

The conversion of heme to oxophlorin was modeled chemically by reacting (py)₂FeII[OEP] with hydrogen peroxide in the strict absence of dioxygen to produce (py)₂Fe[OEPO]. The reaction products were characterized by NMR and a complete assignment of resonances was made. Once the reaction methodology was determined, unsymmetrical porphyrins, such as etio-1 porphyrin, deuteroporphyrin, mesoporphyrin and protoporphyrin IX, in the iron II bis pyridine form, were reacted with hydrogen peroxide and the distribution of isomers determined.; The complexes ClFeIII[meso-R-P] where R is NO₂, CN, OMe, HC(O), n-butyl, and phenyl and the porphyrins are octaethylporphyrin and etio-1porphyrin, were synthesized and characterized by NMR, EPR and UV/Vis spectroscopy. The X-ray crystal structures of ClFeIII[meso-CN-OEP] and ClFeIII [meso-phenyl-OEP] were determined. (CN)₂Fe II[meso-R-OEP] compounds were also synthesized and characterized by NMR and EPR.; The ClFeIII[meso-R-OEP] complexes were reduced to the (py)₂FeII[meso-R-OEP] complexes. They were reacted with hydrogen peroxide at low temperature in the strict absence of oxygen and their products characterized by NMR. The oxidation of the complexes shows specificity for trans, cis or unsubstituted products and the distribution of products is dependent on the nature of the substituent.; Di substituted iron III meso-nitro octaethylporphyrins were synthesized and characterized by NMR. The mono substituted porphyrins were reduced to the iron II bispyridine forms and reacted with dioxygen. The reaction products have been characterized by NMR, UV/Vis and mass spectrometry. Reaction products are stable in the absence of oxygen, however decomposition occurs in the presence of oxygen. These decomposition products have been characterized by NMR and UV/Vis spectroscopy.; Meso-formyl substituted iron III porphyrins were synthesized and characterized by NMR. Reduction, for varying lengths of time, to the bispyridine iron II complex produces a mixture of products, characterized by NMR. Two of the products have been identified as (py)₂FeII[ meso-HC(O)-OEP] and (py)₂FeII[ meso-CH₂OH-OEP]. The reduction products were reacted separately with hydrogen peroxide and dioxygen. The reaction products were characterized by NMR. Additionally, cyanide and methanol were reacted with meso -formyl iron III porphyrins and the reaction products characterized by NMR.