A series of mononuclear metal compounds [MII(L1SCH3)Cl2] (M = Co, Cu, Fe, Mn, L1SCH3 = 2-(methylthio)-N,N-bis(pyridin-2-ylmethyl)aminoethane) has been synthesized and characterized. The structures... Show moreA series of mononuclear metal compounds [MII(L1SCH3)Cl2] (M = Co, Cu, Fe, Mn, L1SCH3 = 2-(methylthio)-N,N-bis(pyridin-2-ylmethyl)aminoethane) has been synthesized and characterized. The structures and spectroscopic properties of these compounds are compared to the related dinuclear compounds [MII2(L1SSL1)Cl4] (M = Co, Cu, Fe), which were obtained from the reactions of disulfide ligand L1SSL1 with the corresponding metal chloride salts (L1SSL1 = di-2-(bis(2-pyridylmethyl)amino)-ethyl disulfide). The crystal structures show that the metal centers in the mononuclear compounds [CoII(L1SCH3)Cl2], [CuII(L1SCH3)Cl2] and [MnII(L1SCH3)Cl2] are in trigonal-bipyramidal geometries coordinated by three nitrogen donors of the tetradentate ligand and two chloride ions, with configurations similar to that of metal centers in [CoII2(L1SSL1)Cl4] and [CuII2(L1SSL1)Cl4]. In contrast, the iron(II) center in [FeII(L1SCH3)Cl2] is coordinated by three nitrogen donors and one sulfur atom of the tetradentate ligand and two chloride ions in an octahedral geometry, which is similar to the geometry of one of the Fe(II) centers in the dinuclear compound [FeII2(L1SSL1)Cl4], where two iron(II) centers are in different geometries. UV–vis spectra of the mononuclear compounds are comparable to those of the related dinuclear compounds. Show less
Luo, S.; Bruggeman, D.F.; Siegler, M.A.; Bouwman, E. 2018
A large-scale purification procedure has been developed to isolate the membrane-bound bc(1) complex of Paracoccus denitrificans. From the purified complex, a water-soluble fragment has been... Show moreA large-scale purification procedure has been developed to isolate the membrane-bound bc(1) complex of Paracoccus denitrificans. From the purified complex, a water-soluble fragment has been isolated. The fragment comprising residues 50-190 contains the Rieske [2Fe-2S] cluster and has an optical spectrum which is typical of such a cluster. The EPR spectrum of the cluster in the bc(1) complex differs slightly from the spectrum of the water-soluble fragment. Differences in the g values and linewidths of the resonances can be attributed to the absence of bound quinone in the water-soluble fragment. Signals from the cysteines and histidines that coordinate to the [2Fe-2S] cluster could be identified in the H-1 NMR spectrum of the fragment in solution. (C) 1998 Elsevier Science S.A. All rights reserved. Show less
Adman, E.T.; Canters, G.W.; Hill, H.A.O.; Kitchen, N.A. 1983