Toxicity, Antibacterial, Antioxidant, Antidiabetic, and DNA Cleavage Effects of Dextran-Graft-Polyacrylamide/Zinc Oxide Nanosystems.

Synthesis of metal oxide nanoparticles-polymer nanocomposites is an emerging strategy in nanotechnology to improve targeted delivery and reduce the toxicity of nanoparticles. In this study, we report biological effects of previously described hybrid nanocomposites containing dextran-graft-polyacrylamide/zinc oxide nanoparticles (D-PAA/ZnO NPs) prepared from zinc sulfate (D-PAA/ZnONPs(SO)) and zinc acetate (D-PAA/ZnONPs(-OAc)) focusing primarily on their antimicrobial activity. D-PAA/ZnONPs(SO) and D-PAA/ZnONPs(-OAc) nanosystems were tested in a complex way to assess their antioxidant activity (DPPH assay), antidiabetic potential (α-amylase inhibition), DNA cleavage activity, antimicrobial, and antibiofilm activity.

Crystal structure of polymeric bis-(3-amino-1-pyrazole)-cadmium diiodide.

The reaction of cadmium iodide with 3-amino-pyrazole (3-apz) in ethano-lic solution leads to tautomerization of the ligand and the formation of crystals of the title compound, -poly[[di-iodido-cadmium(II)]-bis-(μ-3-amino-1-pyrazole)-κ : ;κ : ], [CdI(CHN)] or [CdI(3-apz)] . Its asymmetric unit consists of a half of a Cd cation, an iodide anion and a 3-apz mol-ecule. The Cd cations are coordinated by two iodide anions and two 3-apz ligands, generating -CdNI octa-hedra, which are linked into chains by pairs of the bridging ligands.

Crystal structure of polymeric bis-(3-amino-1-pyrazole)-cadmium dibromide.

The reaction of cadmium bromide tetra-hydrate with 3-amino-pyrazole (3-apz) in ethano-lic solution leads to tautomerization of the ligand and the formation of crystals of the title compound, -poly[[di-bromido-cadmium(II)]-bis-(μ-3-amino-1-pyrazole)-κ : ;κ : ], [CdBr(CHN)] or [CdBr(3-apz)]. Its asymmetric unit consists of a half of a Cd cation, a bromide anion and a 3-apz mol-ecule. The Cd cations are coordinated by two bromide anions and two 3-apz ligands, generating -CdNBr octa-hedra, which are linked into chains by pairs of the bridging ligands.

Crystal structure and Hirshfeld surface analysis of poly[[tetra-aqua-(μ-1,3,4,7,8,10,12,13,16,17,19,22-dodeca-aza-tetra-cyclo-[8.8.4.1.1]tetra-cosane-5,6,14,15,20,21-hexaonato)iron(IV)dilithium] tetra-hydrate].

The title compound, [FeLi(CHNO)(HO)]·4HO, consists of iron complex anions, lithium cations and water mol-ecules. The complex anion shows a clathrochelate topology. The coordination geometry of the Fe centre is inter-mediate between a trigonal prism and a trigonal anti-prism.

-Poly[[tetra-kis-(3,5-dimethyl-1-pyrazole-κ )copper(II)]-μ-sulfato-κ :']: crystal structure and Hirshfeld surface analysis of a Cu coordination polymer.

The title coordination polymer, [Cu(SO)(CHN)] , was synthesized using a one-pot reaction of copper powder, anhydrous copper(II) sulfate and 3,5-dimethyl-1-pyrazole (Hdmpz) in aceto-nitrile under ambient conditions. The asymmetric unit can be described as a chain consisting of four [Cu(SO)(Hdmpz)] formula units that are connected to each other by a μ-sulfato-bridged ligand. The octa-hedral coordination geometry (ON) of all copper atoms is realized by coordination of four pyrazole ligands and two sulfate ligands.

Crystal structure and Hirshfeld surface analysis of di-μ-chlorido-bis-[(aceto-nitrile-κ)chlorido-(ethyl 5-methyl-1-pyrazole-3-carboxyl-ate-κ ,)copper(II)].

The title compound, [CuCl(CHNO)(CHCN)] or [Cu(μ-Cl)(CH-Pz-COOCHCH)Cl(CHCN)], was synthesized using a one-pot reaction of copper powder, copper(II) chloride dihydrate and ethyl 5-methyl-1-pyrazole-3-carboxyl-ate (CH-Pz-COOCHCH) in aceto-nitrile under ambient conditions. This complex consists of discrete binuclear mol-ecules with a {Cu(μ-Cl)} core, in which the Cu⋯Cu distance is 3.8002 (7) Å.

Crystal structure of bis-{μ-2-[bis-(2-hy-droxy-eth-yl)amino]-ethano-lato}bis-(μ-3,5-di-methyl-pyrazolato)tricopper(II) dibromide sesquihydrate.

In the title bicyclic trinuclear pyrazolate amino-alcohol complex, [Cu(CHN)(CHNO)]Br·1.5HO, the central Cu atom lies on a center of symmetry and is involved in the formation of two five-membered rings. It has a coordination number of 4, is in a distorted tetra-hedral environment and is connected by the bridging oxygen atoms of the deprotonated OH groups of different amino-alcohol groups, and by the N atoms of deprotonated di-methyl-pyrazole ligands.

Crystal structure of di-chlorido-1κ,2κ-(μ-3,5-dimethyl-1-pyrazolato-1κ :2κ )(3,5-dimethyl-1-pyrazole-2κ ){μ-2-[(2-hy-droxy-eth-yl)amino-1κ ,]ethano-lato-1:2κ :}dicopper(II).

The title compound, [Cu(CHN)(CHNO)Cl(CHN)], is a pyrazolate amino-alcohol complex which contains two di-methyl-pyrazole mol-ecules in monodentate and bidentate-bridged coordination modes and a monodeproton-ated di-ethano-lamine mol-ecule. Both copper atoms are involved in the formation of non-planar five-membered chelate rings. One Cu atom is in a distorted tetra-hedral environment formed by the pyridine nitro-gen atom of the protonated di-methyl-pyrazole mol-ecule, the N atom of the deprotonated bridged di-methyl-pyrazole, the Cl atom and the bridged O atom of the monodeprotonated di-ethano-lamine.

Synthesis, crystal structure, spectroscopic features and Hirshfeld surfaces of 2-methyl-3-[(2-methyl-phen-yl)carbamo-yl]phenyl acetate.

The title compound, CHNO, was synthesized, characterized by IR spectroscopy and its crystal structure was determined from single-crystal diffraction data. The asymmetric unit contains two mol-ecules, which adopt different conformations. In one mol-ecule, the acet-oxy and the terminal 2-methyl-phenyl groups are positioned on opposite sides of the plane formed by the central benzene ring, whereas in the other mol-ecule they lie on the same side of this plane.

Crystal structure and Hirshfeld surface analysis of ()-2,4-di--butyl-6-[(3-chloro-4-methyl-phenyl-imino)-meth-yl]phenol.

The title Schiff base compound, CHClNO, shows mirror symmetry with all its non-H atoms, except the -butyl groups, located on the mirror plane. There is an intra-molecular O-H⋯N hydrogen bond present forming an (6) ring motif. In the crystal, the mol-ecules are connected by C-H⋯π inter-actions, generating a three-dimensional supra-molecular structure.

Combined analysis of chemical bonding in a Cu(II) dimer using QTAIM, Voronoi tessellation and Hirshfeld surface approaches.

Interaction of 1-(1H-pyrazol-5-yl)ethanone oxime (H2PzOx) with copper(II) chloride in the presence of pyridine afforded a binuclear discrete [Cu2(HPzOx)2Cl2py2] complex, which was characterized by Fourier transform-IR and electron paramagnetic resonance (EPR) spectra, magnetochemistry and high-resolution X-ray diffraction experiments. Multipole refinement of X-ray diffraction data and density-functional theory (DFT) calculations of an isolated molecule allowed charge and spin distributions to be obtained for this compound. Magnetochemistry data, EPR spectra and DFT calculations of an isolated molecule show antiferromagnetic coupling between copper(II) ions.

[Di-aqua-sesqui(nitrato-κO)hemi(perchlorato-κO)copper(II)]-μ-{bis-[5-methyl-3-(pyridin-2-yl)-1H-pyrazol-4-yl] selenide}-[tri-aqua-(perchlorato-κO)copper(II)] nitrate monohydrate.

In the binuclear title complex, [Cu2(ClO4)1.5(NO3)1.5(C18H16N6Se)(H2O)5]NO3·H2O, both Cu(II) ions are hexa-coordinated by O and N atoms, thus forming axially elongated CuO4N2 octa-hedra.

[Aqua-bis-(nitrato-κO)copper(II)]-μ-{bis-[5-methyl-3-(pyridin-2-yl)-1H-pyrazol-4-yl]selenide}-[diaqua-(nitrato-κO)copper(II)] nitrate monohydrate.

In the title binuclear complex, [Cu2(NO3)3(C18H16N6Se)(H2O)3]NO3·H2O, the Cu(II) ions are penta-coordinated in a tetra-gonal-pyramidal geometry. In both cases, the equatorial planes are formed by a chelating pyrazole-pyridine group, a water mol-ecule and a nitrate O atom, whereas the apical positions are occupied by a water mol-ecule for one Cu(II) ion and a nitrate O atom for the other. The organic selenide ligand adopts a trans configuration with respect to the C-Se-C plane.

(3-Acetyl-5-carboxyl-ato-4-methyl-1H-pyrazol-1-ido-κ(2) N (1),O (5))aqua-[(pyridin-2-yl)methanamine-κ(2) N,N']copper(II).

In the title compound, [Cu(C7H6N2O3)(C6H8N2)(H2O)], the Cu(II) ion is in a distorted square-pyramidal N3O2 environment formed by two bidentate chelating ligands in the equatorial coordination sites and one water mol-ecule in the apical direction. In the crystal, O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds link the complex mol-ecules into a three-dimensional supra-molecular network.

Bis{4-[(3,5-dimethyl-1H-pyrazol-4-yl)selan-yl]-3,5-dimethyl-1H-pyrazol-2-ium} chloride monohydrate.

In the title compound, 2C(10)H(15)N(4)Se(+)·Cl(-)·OH(-), a singly protonated mol-ecule of the organic selenide participates in hydrogen bonding with neighboring mol-ecules, forming zigzag chains along [001]. The molecule adapts a cis bridging mode with a C-Se-C angle of 102.13 (15)°.

Dibromidobis(3,5-dimethyl-1H-pyrazole-κN)cobalt(II).

In the mononuclear title complex, [CoBr(2)(C(5)H(8)N(2))(2)], the Co(II) atom is coordinated by two N atoms from two monodentate 3,5-dimethyl-pyrazole ligands and two Br atoms in a highly distorted tetra-hedral geometry. In the crystal, the complex mol-ecules are linked by inter-molecular N-H⋯Br hydrogen bonds into chains along [101]. An intra-molecular N-H⋯Br hydrogen bond is also present.

(Tris{2-[(5-hy-droxy-pyridin-2-yl-κN)methyl-idene-imino-κN]eth-yl}amine)-zinc dinitrate.

In the complex cation of the title compound, [Zn(C(24)H(27)N(7)O(3))](NO(3))(2), the tripodal tris-{[2-(5-hy-droxy-pyridin-2-yl)methyl-idene-imino]-eth-yl}amine ligand is coordin-ated to the Zn atom through the three pyridine and three imino N atoms. The coordination sphere of the Zn atom is based on an octahedron with a significant distortion towards trigonal prismatic, the twist angle being 45.58 (9)°.

3,5-Dimethyl-4-nitroso-1H-pyrazole.

In the unit cell of the title compound, C(5)H(7)N(3)O, there are two conformers (A and B) which differ in the position of the oxime group with respect to the protonated pyrazole nitro-gen (trans in the A conformer and cis in the B conformer) and in the geometric parameters. The oxime group exists in the nitroso form in both conformers. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O and N-H⋯N hydrogen bonds into zigzag-like chains along the b axis.

cyclo-Tetra-kis(μ-3-acetyl-4-methyl-1H-pyrazole-5-carboxyl-ato-κN,O:N,O)tetra-kis[aqua-copper(II)] tetra-deca-hydrate.

The title compound, [Cu(4)(C(7)H(6)N(2)O(3))(4)(H(2)O)(4)]·14H(2)O, a tetra-nuclear [2 × 2] grid-type complex with S4 symmetry, contains four Cu(II) atoms which are bridged by four pyrazole-carboxyl-ate ligand anions and are additionally bonded to a water molecule. Each Cu(II) atom is coordinated by two O atoms of the carboxyl-ate and acetyl groups, two pyrazole N atoms of doubly deprotonated 3-acetyl-4-methyl-1H-pyrazole-5-carb-oxy-lic acid and one O atom of a water mol-ecule. The geometry at each Cu(II) atom is distorted square-pyramidal, with the two N and two O atoms in the equatorial plane and O atoms in the axial positions.

1-{3-[1-(Hydroxyimino)ethyl]-4-methyl-1H-pyrazol-5-yl}ethanone.

In the title compound, C(8)H(11)N(3)O(2), the oxime and the acetyl groups adopt a transoid conformation, while the pyrazole H atom is localized in the proximity of the acetyl group and is cis with respect to the acetyl O atom. In the crystal, dimers are formed as the result of hydrogen-bonding inter-actions involving the pyrazole NH group of one mol-ecule and the carbonyl O atom of another. The dimers are associated into sheets via O-H⋯N hydrogen bonds involving the oxime hydroxyl and the unprotonated pyrazole N atom, generating a macrocyclic motif with six mol-ecules.

Chloridotris(3,5-dimethyl-1H-pyrazole-κN)(formato-κO)copper(II)-dichlorido-bis(3,5-dimethyl-1H-pyrazole-κN)copper(II) (2/1).

The asymmetric unit of the title compound, [Cu(CHO(2))Cl(C(5)H(8)N(2))(3)](2)·[CuCl(2)(C(5)H(8)N(2))(2)] or 2[A]·[B], contains one A mol-ecule and one half-molecule of B, located on a centre of inversion. The Cu(II) environments in A and B are different. In A, the Cu(II) atom is coordinated by three N atoms from three 3,5-dimethyl-1H-pyrazole (L) ligands, one O atom from a formate ligand and a chloride anion in an axial position [Cu-Cl = 2.

catena-Poly[[[aqua-copper(II)]-bis-[μ-bis-(3,5-dimethyl-1H-pyrazol-4-yl) selenide-κN:N]] dichloride monohydrate].

In the title compound, {[Cu(C(10)H(14)N(4)Se)(2)(H(2)O)]Cl(2)·H(2)O}(n), the Cu(II) ion, lying on a twofold rotation axis, has a square-pyramidal geometry constituted by four N atoms of pyrazolyl groups in the basal plane and an apical O atom of a water mol-ecule. A pair of bis-(3,5-dimethyl-1H-pyrazol-4-yl) selenide ligands bridge the Cu centers into a polymeric double-chain extending along [001]. The chloride anions are involved in inter-molecular N-H⋯Cl and O-H⋯Cl hydrogen bonds, which link the chains into a three-dimensional network.

catena-Poly[[[aqua-copper(II)]bis-[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide]] bis-(tetra-fluorido-borate) bis-(triphenyl-phosphine oxide) monohydrate].

The title compound, {[Cu(C(10)H(14)N(4)Se)(2)(H(2)O)](BF(4))(2)·2C(18)H(15)PO·H(2)O}(n), has a polymeric structure where each Cu(II) ion adopts a square-pyramidal coordination constituted by four N atoms of pyrazole moieties in the equatorial plane and an axial O atom of a water mol-ecule. A pair of bis-(3,5-dimethyl-1H-pyrazol-4-yl) selenide ligands bridges the Cu(II) centres into a chain extending along the c axis. The water mol-ecules, anions and triphenyl-phosphine oxide mol-ecules are involved in inter-molecular hydrogen bonding, which links the chains into a three-dimensional network.

Efficient catalytic phosphate ester cleavage by binuclear zinc(II) pyrazolate complexes as functional models of metallophosphatases.

A series of dizinc(II) complexes based on the pyrazolate ligands 3-[(1E)-N-hydroxyethanimidoyl]-4-methyl-1H-pyrazole-5-carboxylic acid (H(3)L(1)), (1E,1'E)-1,1'-(4-methyl-1H-pyrazole-3,5-diyl)diethanone dihydrazone (HL(2)), (E,E)-(4-methyl-1H-pyrazole-3,5-diyl)bis(methylmethanone) dioxime (H(3)L(3)), (E,E)-(4-phenyl-1H-pyrazole-3,5-diyl)bis(phenylmethanone) dioxime (H(3)L(4)), and 1H-pyrazole-3,5-dicarboxylic acid (H(3)L(5)) have been synthesized and investigated as functional models of phosphoesterases, focusing on correlations between the hydrolytic activity and molecular parameters of the bimetallic core. Speciation of the various dizinc complexes in solution has been determined potentiometrically, and the structures in the solid state have been established by X-ray crystallography. The hydrolysis of two phosphoesters, an RNA model 2-hydroxypropyl-p-nitrophenyl phosphate (HPNP) and the pesticide paraoxon-ethyl (POE), promoted by the dinuclear phosphoesterase model complexes has been investigated in DMSO/buffered water (1:1) at 50 degrees C as a function of complex concentration, substrate concentration, and pH.

Bis(acetato-κO,O')bis-(3,5-dimethyl-1H-pyrazole-κN)copper(II).

In the title compound, [Cu(C(2)H(3)O(2))(2)(C(5)H(8)N(2))(2)], the Cu(II) atom has a distorted tetra-gonal-bipyramidal geometry, with the equatorial plane formed by two N atoms belonging to two 3,5-dimethyl-1H-pyrazole ligands and two O atoms from two acetate anions. The second O atoms of the acetate groups provide elongated Cu-O axial contacts, so that the acetates appear to be coordinated in a pseudo-chelate fashion. The pyrazole ligands are situated in cis positions with respect to each other.