122413-32-5Relevant articles and documents
Influence of the metals and ligands in dinuclear complexes on phosphopeptide sequencing by electron-transfer dissociation tandem mass spectrometry
Asakawa, Daiki,Miyazato, Akio,Rosu, Frédéric,Gabelica, Valérie
, p. 26597 - 26607 (2018)
Phosphorylation is one of the most important protein modifications, and electron-transfer dissociation tandem mass spectrometry (ETD-MS/MS) is a potentially useful method for the sequencing of phosphopeptides, including determination of the phosphorylatio
Dioxygen binding to diferrous centers. Models for diiron-oxo proteins
Dong, Yanhong,Ménage, Stéphane,Brennan, Bridget A.,Elgren, Timothy E.,Jang, Ho G.,Pearce, Linda L.,Que Jr., Lawrence
, p. 1851 - 1859 (1993)
Dioxygen adducts of [Fe2L(O2CC6H5)]X2, where L represents the dinucleating ligands HPTB (anion of N,N,-N′,N′-tetrakis(2-benzimidazolylmethyl)-2-hydroxy-1,3- diaminopropane), its N-ethyl analogue, and its tetrakis(pyridine) analogue, HPTP, can form and serve as models for the putative oxygenated intermediates of methane monooxygenase and ribonucleotide reductase. [Fe2(N-Et-HPTB)(O2CC6H5)](BF 4)2 (1) crystallizes in the triclinic space group P1 with cell constants a = 13.04 (1) ?, b = 14.248 (7) ?, c = 18.09 (1) ?, α = 73.56 (6)°, β = 78.22 (7)°, γ = 67.71 (6)°, V = 2963 (9) ?3, Z = 2; R = 0.069, and Rw = 0.085. The Fe(II) sites are bridged by the alkoxide of the dinucleating ligand and a benzoate, affording a diiron core with an Fe-μ-O-Fe angle of 124.0 (3)° and an Fe-Fe distance of 3.473 (7) ?. Both Fe(II) centers have trigonal bypyramidal geometry, and NMR studies show that the remaining coordination sites are accessible to ligands such as DMSO and Ph3PO. The iron centers are antiferromagnetically coupled with J ~～ 20-26 cm-1 (? = JS1·S2). Irreversible dioxygen adducts form upon exposure of the diferrous complexes to O2 at low temperatures. The 1/O2 adduct and its HPTB analogue, 2/O2, are stable indefinitely in CH2Cl2 at -60°C but decompose upon warming; the addition of DMSO or other polar aprotic solvents further stabilizes the adducts, allowing them to persist for short periods even at ambient temperature. The adduct of the pyridine analogue, 3/O2, on the other hand, is not observed at -80°C unless a polar aprotic solvent is added to the CH2Cl2 solution. The adducts exhibit visible absorption maxima near 600 nm and resonance Raman features at ～470 cm-1 (ν(Fe-O)) and ～890-900 cm-1 (ν(O-O)). The latter is characteristic of a μ-1,2-peroxo species; in support, the NMR properties of the HPTB adducts indicate the presence of a moderately strong antiferromagnetic coupling interaction (J ～ 140 cm-1). Carboxylate substitution on 1 effects a shift of the absorption maximum of the adduct, indicating that the carboxylate remains coordinated in the adduct. Thus, the adducts are proposed to have tribridged (μ-1,2-peroxo)(μ-carboxylato)(μ-alkoxo)diferric cores. The differing stabilities of the dioxygen adducts are also reflected in differences in reactivity. The addition of 2,4-di-tert-butylphenol or Ph3P does not affect the 1/O2 adduct at -50°C but does accelerate the decomposition of the 3/O2 adduct, affording 0.5-0.6 equiv of the corresponding biphenol or OPPh3, respectively. The one-electron oxidation of a phenol by 3/O2 suggests that such an oxygenated species may be involved in the mechanism of the tyrosyl radical formation in ribonucleotide reductase; however, some further activation step is likely to be required for such a species to participate in the alkane hydroxylation mechanism of methane monooxygenase.
Catalytic oxidation of dibenzothiophene and thioanisole by a diiron(III) complex and hydrogen peroxide
Trehoux, Alexandre,Roux, Yoann,Guillot, Régis,Mahy, Jean-Pierre,Avenier, Frédéric
, p. 40 - 46 (2015/02/18)
One diiron(III) complex of the dinucleating ligand HPTP (N,N,N′,N′-tetrakis(2-pyridylmethyl)-2-hydroxy-1,3-diaminopropane) and one mononuclear iron(III) complex of the BPMEN ligand (N,N′-dimethyl-N,N′-bis-2-pyridinylmethyl)-1,2-ethanediamine) have been synthesized and characterized by X-ray diffraction analysis, high resolution mass spectrometry, and electronic absorption spectroscopy. The diiron(III) complex reacts with hydrogen peroxide to generate a short lived blue intermediate comparable to the previously described μ-peroxo-diiron(III) intermediate, obtained from the interaction of the corresponding HPTP diiron(II) complex with dioxygen. Both mononuclear and dinuclear iron complexes were tested for the catalytic oxidation of sulphides with H2O2, and the diiron complex showed good activity for the oxidation of dibenzothiophene (DBT), a fuel contaminant naturally present in crude oil. It catalyzed the total conversion of DBT into the corresponding sulfone via the formation of the sulfoxide, in acetonitrile at room temperature.
Nucleotide cleaving agents and method
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, (2008/06/13)
The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.
