manganese ore deposits occurred in various types of syngenetic, diagenetic and epigenetic mineralization in association with radiolarian cherts in colored melange of neyriz ophiolite in abadeh tashk area, eastern fars province. microscopic study and xrd analyses show a simple mineralogy for manganese compounds in all types. psylomelane and braunite are the primary manganese compounds in syngene...

Apoproteins of cytochrome c peroxidase, horseradish peroxidase, and sperm whale myoglobin were recombined with manganese complexes of proto-, hemato-, meso-, and deuteroporphyrins to form manganese porphyrin-protein complexes. These complexes were purified by column chromatography. All the manganese porphyrin-containing cytochrome c peroxidases were crystallized. Light absorption maxima of mang...

A set of six multinuclear manganese complexes was screened for the ability to catalyse reactions yielding O(2) under coherent experimental conditions; we identify a much larger number of manganese compounds than previously known that catalyse oxygen formation.

New manganese compounds [Mn(HphpzMe)(2)(H(2)phpzMe)(HCO(2))] (1), [Mn(2)(phpzMe)(2)(HphpzMe)(2)(OCH(3))]·2CH(3)OH (2), Na{[Mn(HphpzPh)(phpzPh)(MeOH)(2)](2)}(HCO(2)) (3), [Mn(HphpzPh)(2)(EtOH)(2)]ClO(4)·2EtOH (4) and [Mn(HphpzPh)(2)N(3)] (5) were synthesized and characterized with various techniques. 1, 4 and 5 are mononuclear manganese(III) compounds, 2 is a mixed-valence dinuclear manganese(II...

There has been a tremendous surge in research on the synthesis of various metal compounds aimed at simulating the water-oxidizing complex (WOC) of photosystem II (PSII). This is crucial because the water oxidation half reaction is overwhelmingly rate-limiting and needs high over-voltage (approx. 1 V), which results in low conversion efficiencies when working at current densities required for hy...

The synthesis of (diarylmethyl)sulfonamides and related compounds by a new manganese-mediated, cobalt-catalyzed three-component reaction between sulfonamides, carbonyl compounds and organic bromides is described. This organometallic Mannich-like process allows the formation of the coupling products within minutes at room temperature. A possible mechanism, emphasizing the crucial role of mangane...

The use of the highly sterically demanding Cp(BIG) ligand (Cp(BIG) = C5(4-nBuC6H4)5) and white phosphorus (P4) enables the synthesis of new P-rich derivatives of the rare Pn ligand complexes of manganese. The obtained complexes, [{Cp(BIG)Mn}2(μ,η(5:5)-P5)] (2) and [{Cp(BIG)Mn}2(μ,η(2:2)-P2)2] (3), exhibit the highest number of P atoms in this class of manganese compounds identified by X-ray str...

This contribution provides an analysis of the basic coordination tendencies of manganese with specific emphasis on the biological chemistry of this element. The review is broken into four parts. First, a discussion of the basic coordination chemistry o f manganese is mononuclear and multinuclear environments is prescnted. Second, the biophysical data essential to the development of models for t...

Synthetic catalytic scavengers of reactive oxygen species (ROS) may have broad clinical applicability. In previous papers, two salen-manganese complexes, EUK-8 and EUK-134, had superoxide dismutase (SOD) and catalase activities and prevented ROS-associated tissue injury. This study describes two series of salen-manganese complexes, comparing catalytic ROS scavenging properties and cytoprotectiv...