Iron and zinc porphyrin linked MoO(dithiolene) complexes in relevance to electron transfer between Mo-cofactor and cytochrome in sulfite oxidase.

Oxo-molybdenum (dithiolene) complexes covalently linked individually to iron and zinc porphyrin have been synthesized to show an electron transfer between the two metal centres in relevance to electron transfer from Mo-cofactor to cytochrome domains in the oxidative half of the catalytic cycle of native sulfite oxidase. This association has been investigated by electrochemical, EPR measurement and X-ray absorbance spectroscopy techniques.

Zinc protoporphyrin-trimethylamine-N-oxide complex involves cholesterol oxidation causing atherosclerosis.

Metabolism of food protein by gut microbes produce trimethylamine which on oxidation by hepatic flavin-containing monooxygenases is transformed to trimethylamine-N-oxide (TMAO). TMAO has recently been implicated as a biomarker for atherosclerosis. TMAO, as (CH)N-O), is ionic and so a hydrophilic molecule that is freely available in blood plasma.