Two new cyclen derivatives, H(2)do2nph and H(2)cb-do2nph, containing two trans-2-methyl-4-nitrophenol pendant arms and the latter including also an ethylene cross-bridge, were prepared in good yields using the bisaminal synthetic route. The two ligands were studied comparatively regarding their metal complexation behaviour. The copper(II) and zinc(II) complexes of H(2)do2nph and H(2)cb-do2nph w...

As it was established in our previous studies, the proteins of human serum γ-globulin fraction could interact with copper or zinc ions distributed in the periglobular space, form metal complexes, and become able to perform effector functions differing due to the conformational shifts from those mediated by them in native conformation of their Fc regions. In the present work we have evaluated ab...

Flower-shaped inorganic nanocrystals have been used for applications in catalysis and analytical science, but so far there have been no reports of 'nanoflowers' made of organic components. Here, we report a method for creating hybrid organic-inorganic nanoflowers using copper (II) ions as the inorganic component and various proteins as the organic component. The protein molecules form complexes...

Cysteine-containing peptide oxidation was studied both by using an inert platinum electrode and a sacrificial electrode (copper or zinc) generating metallic ions in electrospray ionization mass spectrometry (ESI-MS). Using peptides containing one, two and three cysteines, we have compared the different chemical and electrochemical oxidation pathways of cysteine (RS(-II)H) to cystine (RS(-I)S(-I...

The tryptophan metabolite, quinolinic (2,3-pyridinedicarboxylic) acid, is known as an endogenous neurotoxin. Quinolinic acid can form coordination complexes with iron or copper. The effects of quinolinic acid on reactive oxygen species production in the presence of iron or copper were explored by a combination of chemical assays, classical site-specific and ascorbic acid-free variants of the de...

A new tetradentate N2O2 Schiff base ligand (MeO-bph)2bn = N,N¢-bis(2-hydroxy-4-methoxybenzophenone)-1,4-butanediamine was prepared from the condensation of butane-1,4-diamine with 4-methoxy-2-hydroxybenzophenone and characterized by 1H-NMR spectroscopy and single-crystal X-ray diffraction. Its nickel(II) and copper(II) complexes characterized usin...

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 magnetic ...

The extraction and separation of copper(II), zinc(II), cobalt(II), and cadmium(II) were investigated. Both copper(II) and zinc(II) formed ammine-complexes, while cadmium(II) and cobalt(II) formed hydroxide precipitates in an ammonia medium. By the addition of sodium dodecylsulfate (SDS), a copper(II) complex formed an ion-pair (copper-ammine-DS), which was extracted into the SDS phase. However,...

The synthesis and characterization of some new binuclear copper (II) complexes, based on the use of large, pyrole-containing macrocycles, the so called "expanded porphyrins", [Cu2(macrocycle)]+4 is described. Electron Spin Resonance (ESR) studies indicate a weak "half-field line", which is characteristic of the Cu(II)-Cu(II) dimer, is observed at about 1600G. The obser...

Copper complexes obtained from the reactions between 2-thiouracil and cupric hydroxide in different solvents have been investigated. Mononuclear or polynuclear complexes of Cu(I) have been obtained depending on the reaction conditions. Hydroxo complexes of copper(I) have been obtained at pH around 3.5. 2-Thiouracil acts as monoor bidentate ligand in complexes. [Cu(H2TU)2 OH], [Cu5(H2TU)6 (OH)5]...