This work is devoted to a study of the structural changes in a single crystal of ammonium nitrate, NH4NO3, doped with copper(II) cations by electron paramagnetic resonance. Ammonium nitrate crystallizes at atmospheric pressure in several polymorphic forms, phase VII → V → IV → III → II → I → melt, with transition temperatures of 103 K, 255 K, 305 K, 357 K, 398 K, and 443 K, respectively. The ai...

Histamine chelation of copper(I) by a terminal histidine residue in copper hydroxylating enzymes activates dioxygen to form unknown oxidants, generally assumed as copper(II) species. The direct formation of copper(III)-containing products from the oxygenation of histamine-ligated copper(I) complexes is demonstrated here, indicating that copper(III) is a viable oxidation state in such products f...

In this paper we present a first insight into the cytotoxic action mode of copper(I) iodide or copper(I) thiocyanate complexes with a phosphine derivative of sparfloxacin (a 3rd generation fluoroquinolone antibiotic agent) and 2,9-dimethyl-1,10-phenanthroline or 2,2'-biquinoline as auxiliary ligands. The in vitro cytotoxic activity of the new complexes was tested against two cancer cell lines (...

a number of complexes in the series (cu ll'),, where l = [(ch,),c-co-ch-coc( ch,),]-i and l'= 3-(me) c6h,0-, 2,6-(di-me)c6h30-, 4-(oh)c6h?o-, 3- (f) c6h,0-, 4-(br)c6h40-a, nd 3,s-(dl-me)c6h30h- ave been prepared and theu magnetic and optical properties determined. in chloroform, the complexes exhibit two bands in the visible and near uv regions. all complexes show room temperature mag...

ABSTRACT A series of dioxygen complexes of copper, iron, and manganese have been synthesized using bulky tripodal nitrogen ligands, hydrotris(3,5-dialkyl1-pyrazolyl)borate, as models for the active sites in the metalloproteins. A binuclear copper peroxo complex having p-q2:$ coordination mode serves as an accurate model of the active site of oxy-hemocyanin. The reactivities of the complex and r...

The synthesis, spectroscopy and magnetic characterization of five new dinuclear copper(II) complexes are described. All five compounds have the general formula [Cu2(L)4(O-R)2](Cl)2 or [Cu2(L)2(Cl)2](Cl)2, in which R = CH3 or H, L=2, 3 or 4-pyridinemethanol as L2, L3 or L4, respectively. The title compounds consist of dinuclear units with bridging methoxo groups in [Cu2(L4)4(O-CH3)2](Cl)2, hydro...

Copper in bile has been shown by electrophoresis to occur neither as free ions nor complexed to protein but to be associated with a component of the micellar complexes of bile. Solvent fractionation studies suggest that the bile salt components of the lecithin-bile salt complexes are the active binding agents. The effects of specific bile salts on the behaviour of copper during electrophoresis ...

The synthesis and X-ray crystal structures of copper(II) nitrate, copper(I) iodide and zinc(II) bromide complexes of the chiral ligand 2 are described.

Mechanical forces induced by ball-milling agitation enabled the highly efficient and widely applicable synthesis of Cu–carbene complexes from N,N-diaryl-imidazolium salts and metallic copper. The required amount of gaseous dioxygen and insoluble copper could be reduced down to stoichiometric quantities, while reaction rates clearly outperformed those obtained in solution. Utilisation of Cu(0) a...