In the crystal structure of the title compound, [Zn(4)(C(8)H(4)O(4))(4)(C(8)H(12)N(6))(H(2)O)(4)](n), one Zn(II) atom is four-coordinated in a slightly distorted tetra-hedral geometry by two O atoms from benzene-1,3-dicarboxyl-ate (BDC) ligands, one N atom from a 1,4-bis-(1,2,4-triazol-1-yl)butane (BTB) ligand and one water mol-ecule, while a second Zn(II) atom is five-coordinated in a distorte...

The interaction of Zn(II) ions with cyanobacteria Spirulina platensis basic protein C-phycocyanin (C-PC) is studied by fluorescence spectroscopy.Stern–Volmer quenching constant value for Zn(II)–C-PC is determined. The binding energy of Zn(II) ions with C-phycocyanin is determined using equilibrium dialysis and atomic absorption spectroscopy. Cooperative binding of Zn(II) ions with C-phycocyanin...

In the title compound, {[Zn(2)(C(16)H(4)I(2)O(8))(H(2)O)(4)]·2H(2)O}(n), two crystallographically independent Zn(II) atoms are each located on a twofold rotation axis. Both Zn(II) atoms are in distorted octa-hedral coordination geometries: one is coordinated by six O atoms from four carboxyl-ate groups, while the other is coordinated by two carboxyl-ate groups and four water mol-ecules. The tet...

A number of multiresistant bacterial pathogens inactivate antibiotics by producing Zn(II)-dependent β-lactamases. We show that metal uptake leading to an active dinuclear enzyme in the periplasmic space of Gram-negative bacteria is ensured by a cysteine residue, an unusual metal ligand in oxidizing environments. Kinetic, structural and affinity data show that such Zn(II)-cysteine interaction is...

The title compound, [Zn(C(8)H(4)O(4))(C(13)H(14)N(2))](n), was obtained by the hydro-thermal reaction of Zn(OAc)(2)·H(2)O with 1,3-di-4-pyridylpropane (bpp) and isophthalic acid (H(2)ip). The Zn(II) ion is coordinated by two bpp and two ip ligands in a distorted tetra-hedral environment. Each ligand coordinates in a bridging mode to connect Zn(II) ions into a three-dimensional diamondoid-type s...

The asymmetric unit of the title compound, [Zn(NCSe)(2)(C(4)H(4)N(2))(2)], consists of one Zn(II) cation, located on a twofold rotation axis, one seleno-cyanate anion and one pyridazine ligand in general positions. The Zn(II) atom is coordinated by two N-atoms of two pyridazine ligands and two terminal N-bonded seleno-cyanate anions within a slightly distorted tetra-hedral coordination environm...

The stability of Zn(II) and Cu(II) complexes of porphyrin derivatives (pheophytin and mesoporphyrin) to UV-B irradiation was studied by absorbance spectroscopy in 95 % ethanol. The chosen porphyrins and their heavy metal complexes underwent first-order photochemical decomposition. In general, pheophytin was more stable than mesoporphyrin to UV-B irradiation. Moreover, the stabilities of the Zn(...

In this work, we developed a method based on ultrasound-assisted emulsification microextraction (USAEME) for the determination of zinc and copper by flame atomic absorption spectrometry (FAAS). The method is based on the use of the organic solvent carbon tetrachloride (CCl4) as an extraction solvent. In order to obtain a high enrichment factor, the effect of different parameters affecting the c...

The title zinc(II) complexes, [Zn(C34H54N2O2)], (II), and [Zn(C28H42N2O2)(C4H8O)], (III), were obtained as monomeric 1:1 complexes, in contrast with the calcium complexes supported by the same ligand class. Complex (II) crystallizes with two independent molecules in the asymmetric unit, which have similar geometric parameters. The donor atoms in (II) form a distorted trigonal±pyramidal arrangem...