Manganese complexes biology

BIOINORGANIC CHEMISTRY. Study of the mechanisms involved in the behavior of metal-containing molecules in living organisms, e.g., biological transport of iron, the effect of copper on nucleic acid and iiucleupruleins, molybdenum, and manganese complexes, etc. 

Apart from the catalytic properties of the Mn-porphyrin and Mn-phthalo-cyanine complexes, there is a rich catalytic chemistry of Mn with other ligands. This chemistry is largely bioinspired, and it involves mononuclear as well as bi- or oligonuclear complexes. For instance, in Photosystem II, a nonheme coordinated multinuclear Mn redox center oxidizes water the active center of catalase is a dinuclear manganese complex (75, 76). Models for these biological redox centers include ligands such as 2,2 -bipyridine (BPY), triaza- and tetraazacycloalkanes, and Schiff bases. Many Mn complexes are capable of heterolytically activating peroxides, with oxidations such as Mn(II) -> Mn(IV) or Mn(III) -> Mn(V). This chemistry opens some perspectives for alkene epoxidation. 

I) of 5/2. For a mononuclear system, six hyperfine lines are predicted. However, for a multinuclear system containing n Mn ions, as many as 6" lines may be observed. This gives rise to a rich EPR spectroscopy among polynuclear manganese complexes, which has been used extensively in the study of biological manganese systems and model complexes. 

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