Photocatalytic and Luminescent Sensing Properties of Two New 1D Zn(II)-Based Coordination Polymers.

Two new d10-configuration based Zn(II) coordination polymers with formula [Zn2(L)2(2,2'-bipy)2]n (1) and [Zn2(L)2(4,4'-bipy)]n (2) (H2L = 4,4'-{[1,2-phenylenebis-(methylene)]bis(oxy)}dibenzoic acid, 2,2'-bipy= 2,2'-bipyridine and 4,4'-bipy= 4,4'-bipyridine) have been synthesized and characterized. Both the compounds had been used as possible luminescent sensors for detecting nitroaromatic compounds (NACs) and as photocatalysts to photodegrade methyl violet (MV) under UV irradiation. The sensing experiments indicated that 2 displayed selective sensing for m-nitrophenol (MNP) with lower limit of detection (LOD) of 1.14 ppm while photocatalytic experiments indicated that 1 displayed better photocatalytic performance than 2 in photodegrading MV.

A twofold interpenetrating three-dimensional heterometallic metal-organic framework with pcu topology based on 2-methylbiphenyl-4,4'-dicarboxylic acid.

The 2-methylbiphenyl-4,4'-dicarboxylate (mbpdc2-) ligand has versatile coordination modes and can be used to construct multinuclear structures. Despite this, reports of the synthesis of coordination complexes involving this ligand are scarce. The title compound, poly[[triaquadi-µ3-hydroxido-hexakis(µ4-2-methylbiphenyl-4,4'-dicarboxylato)calcium(II)hexazinc(II)] monohydrate], {[CaZn6(C15H10O4)6(OH)2(H2O)3]·H2O}n, has been prepared by the hydrothermal assembly of Zn(NO3)2·6H2O, CaCl2 and 2-methylbiphenyl-4,4'-dicarboxylic acid. Two ZnII atoms adopt a four-coordinated distorted tetrahedral geometry by bonding to three O atoms from three different 2-methylbiphenyl-4,4'-dicarboxylate (mbpdc2-) dianionic ligands and one bridging hydroxide O atom. For the remaining ZnII atom, a five-coordinate environment is completed half the time by one carboxylate O atom, and then the same carboxylate O atom and an aqua O atom are present the other half of the time, giving a six-coordinate environment. The CaII atom is coordinated by six O atoms to give an octahedral coordination geometry. The supramolecular secondary building unit (SBU) is a hamburger-like heptanuclear unit (Zn6CaO30) and these units are interconnected through mbpdc2- carboxylate groups to generate a three-dimensional framework with the pcu topology. The single net leaves voids that are filled by mutual interpenetration of an independent equivalent framework in a twofold interpenetrating architecture. The title compound shows thermal stability up to 673 K. The excitation and luminescence data showed the emission of a bright-blue fluorescence.

A hydrostable and twofold interpenetrating three-dimensional zinc-organic framework with rob topology based on 4,4'-oxydibenzoate and 3,3'-dimethyl-4,4'-bipyridine ligands.

Metal-organic frameworks (MOFs) are a new class of porous materials that have received widespread attention due to their potential applications in gas storage and/or separation, catalysis, luminescence, and so on. The title compound, poly[[(µ2-3,3'-dimethyl-4,4'-bipyridine-κ(2)N:N')bis(µ4-4,4'-oxydibenzoato-κ(4)O:O':O'':O''')dizinc] tetrahydrate], {[Zn2(C14H8O5)2(C12H12N2)]·4H2O}n, has been prepared by the solvothermal assembly of Zn(NO3)2·6H2O, 4,4'-oxydi(benzoic acid) and 3,3'-dimethyl-4,4'-bipyridine. The two Zn(II) atoms adopt the same five-coordinated distorted square-pyramidal geometry (i.e. ZnO4N), bonding to four O atoms from four different 4,4'-oxydibenzoate (oba) ligands and one N atom from a 3,3'-dimethyl-4,4'-bipyridine (dmbpy) ligand. The supramolecular secondary building unit (SBU) is a paddle-wheel [Zn2(COO)4] unit and these units are linked by oba ligands within the layer to form a two-dimensional net parallel to the b axis, with the dmbpy ligands pointing alternately up and down, which is further extended by dmbpy ligands to form a three-dimensional framework with rob topology. The single net leaves voids that are filled by mutual interpenetration of an independent equivalent framework in a twofold interpenetrating architecture. The title compound shows thermal stability up to 673 K and is stable in aqueous solutions in the pH range 5-9. Excitation and luminescence data observed at room temperature show that it emits a bright-blue fluorescence.

Adsorptive removal of phenol from aqueous solution with zeolitic imidazolate framework-67.

ZIF-67(zinc-methylimidazolate framework-67), one of the zeolitic imidazolate frameworks (ZIFs), was used for the removal of phenol from aqueous solutions via adsorption and shows high adsorption capacity for phenol. The thermodynamic and kinetic adsorption behavior of ZIF-67 for phenol in water with concentration ranging from 50 to 300 ppm were investigated in a batch reactor and a ZIF-67 packed column, respectively. The effects of pH, contact time, zeta potential of the adsorbent and temperature on the adsorption behavior were evaluated, and the results demonstrated that the adsorption is primarily brought about by a specific favorable interaction (electrostatic interaction) between phenol and ZIF-67 surface. The suitability of the Langmuir adsorption model to the equilibrium data was investigated for each phenol-adsorbent system, which the results showed that the equilibrium data for all the phenol-sorbent systems fitted the Langmuir model. Thermodynamic parameters such as Gibbs free energy are calculated from the experimental data at different temperatures. The adsorbent could be perfectly regenerated at 120 °C with little loss in the adsorption ability.

Fusion with pep-1, a cell-penetrating peptide, enhances the transmembrane ability of human epidermal growth factor.

Administration of macromolecule compositions in medicine and cosmetics always exhibited low bioavailability due to the limitation of transmembrane transport. Here, human epidermal growth factor (hEGF) was fused with glutathione S-transferase (GST) and Pep-1, the first commercial cell-penetrating peptide, in Escherichia coli. The fusion protein was firstly purified with the affinity chromatography, and then the GST tag was released by TEV protease. Final purification was achieved by the ion exchange chromatography. The biological activities and the transmembrane ability of the obtained products were determined using scratch wound-healing assay, MTT analysis, and immunofluorescence assay. The results showed that both rhEGF and Pep-1-fused hEGF were soluble expressed in E. coli. The fusion of Pep-1 could markedly increase the transmembrane ability of EGF, whereas it did not interfere with the growth-stimulating and migration-promoting functions of hEGF on fibroblasts. This research provided a novel strategy for the transmembrane transport of protein-derived cosmetics or drugs.

Hydrostable and Nitryl/Methyl-Functionalized Metal-Organic Framework for Drug Delivery and Highly Selective CO2 Adsorption.

By using a strategy of introducing hydrophobic groups to the linkers, a hydrostable MOF was constructed based on 5-nitroisophthalate and 2,2'-dimethyl-4,4'-bipyridine coligands, revealing a 3D dia topology structure with a 1D channel parallel to the c axis. TGA, PXRD, and water vapor sorption results show high thermal and water stability for the framework. The framework is very porous and possesses not only high busulfan payloads with an encapsulation efficiency up to 21.5% (17.2 wt %) but also very high CO2 selective capture compared with that of other small gases (i.e., CH4, N2, O2, CO, and H2) at 298 K based on molecular simulations due to the pore surface being populated by methyl and nitryl groups. Furthermore, in vitro MTT assays were conducted on four different cells lines with increasing concentrations of the framework, and the results showed that the framework was nontoxic (cell viability >80%) in spite of the concentrations up to 500 µg/mL.

Quality and antitumour activity evaluation of extract of Hypericum ascyron.

Similarity assessment of complex chromatographic profiles is a potential tool for the identification and quality control of herbal medicinal products to guarantee the expected biological activity. In this paper, a high-performance liquid chromatography method was established for controlling the quality of extract of Hypericum ascyron for the first time. With this method, the correlation coefficients of similarity of 10 batches extract of H. ascyron were >0.97. The extract of H. ascyron displayed steadily inhibitorty activities on the growth of human cervical cancer Hela cell lines. Therefore, the present study successfully set up a sensitive efficient method which might confirm stable biological activity of the extract of H. ascyron.

A three-dimensional zinc-based coordination polymer built from 5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium with a 4-connected sra topology.

A novel three-dimensional Zn(II) complex, poly[aqua(µ4-5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium)zinc(II)], [Zn(C8H5NO4)(H2O)]n, has been prepared by hydrothermal assembly of Zn(CH3COO)2·2H2O and 5-carboxy-1-(carboxymethyl)pyridin-1-ium-2-olate (H2ccop). The ccop(2-) anions bridge the Zn(II) cations in a head-to-tail fashion via monodentate aromatic carboxylate and phenolate O atoms to form an extended zigzag chain which runs parallel to the [011] direction. One O atom of the aliphatic carboxylate group of the ccop(2-) ligand coordinates to the Zn(II) atom of a neighbouring chain thereby producing undulating layers which lie parallel to the (01-1) plane. A similar parallel undulating planar structure can be obtained if a path involving the other O atom of the aliphatic carboxylate group is considered. Thus, the aliphatic carboxylate group acts in a bridging bidentate mode to give extended -Zn-O-C-O-Zn- sequences running parallel to [001] which link the layers into an overall three-dimensional framework. The three-dimensional framework can be simplified as a 4-connected sra topology with a Schläfli symbol of 4(2).6(3).8 if all the Zn(II) centres and ccop(2-) anions are regarded as tetrahedral 4-connected nodes. The three-dimensional luminescence spectrum was measured at room temperature with excitation and emission wavelengths of 344-354 and 360-630 nm, respectively, at intervals of 0.15 and 2 nm, respectively.

Cloning and analysis of bile salt hydrolase genes from Lactobacillus plantarum CGMCC No. 8198.

Genes coding for bile salt hydrolase of Lactobacillus plantarum CGMCC 8198, a novel probiotic strain isolated from silage, were identified, analyzed and cloned. L. plantarum strongly resisted the inhibitory effects of bile salts and also decreased serum cholesterol levels by 20% in mice with hypercholesterolemia. Using RT-PCR analysis, bsh2, bsh3 and bsh4 were upregulated by bile salts in a dose-dependent manner. All three bsh genes had high similarity with those of other Lactobacillus strains. All three recombinant BSHs had high activities for the hydrolysis of glycodeoxycholic acids and taurodeoxycholic acids.

(E)-N-(2,4-Dichloro-benzyl-idene)-2,5-dimeth-oxy-aniline.

In the title compound, C15H13Cl2NO2, which was obtained by a condensation reaction of 2,5-dimeth-oxy-aniline and 2,4-dichloro-benzaldehyde, the dihedral angle between the benzene rings is 51.94 (2)°. The 2,5-dimeth-oxy-phenyl and 2,4-dichloro-phenyl groups are attached to the ends of the N=C group in an E conformation. Intra-molecular C-H⋯Cl and C-H⋯N contacts are observed. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains parallel to the b axis.

trans-Dichloridobis(2,4-dimethyl-aniline-κN)palladium(II).

In the title compound, [PdCl(2)(C(8)H(11)N)(2)], the Pd(II) atom is located on a crystallographic inversion center and adopts a square-planar coordination geometry, with pairs of equivalent ligands in trans positions. In the crystal, adjacent mol-ecules are linked with each other through weak N-H⋯Cl hydrogen bonds and π-π stacking inter-actions between the phenyl rings [shortest centroid-centroid distance = 3.720 (2) Å], leading to the formation of layers parallel to the a-axis direction.

catena-Poly[[diaqua-bis-(formato-κO)cobalt(II)]-µ(2)-2,6-bis-(pyridin-4-yl)-4,4'-bipyridine-κN:N].

In the title complex, [Co(CHO(2))(2)(C(20)H(14)N(4))(H(2)O)(2)](n), the Co(II) ion, lying on an inversion center, is six-coordinated by two O atoms from two monodentate formate ligands, two N atoms from two 2,6-bis-(pyridin-4-yl)-4,4'-bipyridine (4-pybpy) ligands and two water mol-ecules, displaying an octa-hedral geometry. The 4-pybpy ligand, having a twofold rotation axis, functions in a bridging coordination mode, connecting the Co(II) ions into a corrugated chain along [[Formula: see text]01]. The chains are further linked into a three-dimensional supra-molecular network by O-H⋯O, C-H⋯N and C-H⋯O hydrogen bonds and π-π stacking inter-actions between the pyridine rings [centroid-to-centroid distance = 3.743 (2) Å].

catena-Poly[hexaaquamagnesium(II) [bis(µ3-5-nitro-2-oxidoisophthalato)dicopper(II)] dihydrate].

In the centrosymmetric dinuclear anions of the title bimetallic complex, {[Mg(H(2)O)(6)][Cu(2)(C(8)H(2)NO(7))(2)]·2H(2)O}(n), each Cu(II) ion is strongly coordinated by four O atoms in a distorted square-planar geometry. Two of these O atoms belong to phenolate groups and the other two to carboxylate groups from 5-nitro-2-oxidoisophthalate (L1) trianions, derived from 5-nitrobenzene-1,2,3-tricarboxylic acid (O(2)N-H(3)L). The phenolate O atoms bridge the two Cu(II) ions in the anion. In addition, each Cu(II) cation interacts weakly with a symmetry-related carboxylate O atom of an adjacent L1 ligand, giving a square-pyramidal coordination geometry. The copper residue forms a ladder-like linear coordination polymer via L1 ligands. The [Mg(H(2)O)(6)](2+) cations sit on centres of inversion. The polymeric anions, cations and free water molecules are self-assembled into a three-dimensional supramolecular network via O-H···O hydrogen bonds.

A novel one-dimensional zinc coordination polymer containing 4-methylbenzoate and 4,4-bipyridine.

The title compound, catena-poly[[tris(mu-4-methylbenzoato)-kappa(2)O:O;kappa(4)O:O'-(4-methylbenzoato-kappa(2)O,O')dizinc(II)]-mu-4,4'-bipyridine-kappa(2)N:N'], [Zn(2)(C(8)H(7)O(2))(4)(C(10)H(8)N(2))](n), is a novel coordination polymer. The asymmetric unit contains two unique Zn(II) ions, four 4-methylbenzoate ligands and one 4,4'-bipyridine (4,4'-bpy) ligand, all in general positions. The four 4-methylbenzoate ligands link the two Zn(II) centres to form a dinuclear unit, with a Zn...Zn separation of 3.188 (2) A, which can be regarded as a supramolecular secondary building unit (SBU). These SBUs are further bridged by 4,4'-bpy ligands, forming a novel one-dimensional infinite chain. There are pi-pi stacking interactions between the benzene rings of the 4-methylbenzoate ligands and the pyridyl rings of the 4,4'-bpy ligands, leading to the formation of a corrugated layer. These layers are further assembled via C-H...O hydrogen bonds into a three-dimensional supramolecular network structure. Coordination polymers such as the title compound are of interest for their potential applications as functional materials.

Poly[aqua-(µ(2)-oxalato)(4-oxidopyri-din-ium)erbium(II)].

The title complex, [Er(C(5)H(5)NO)(C(2)O(4))(H(2)O)](n), is a new erbium polymer based on oxalate and 4-oxidopyridinium ligands. The Er(II) center is coordinated by six O atoms from three oxalate ligands, one O atom from a 4-oxidopyridinium ligand and one water mol-ecule, and displays a distorted square-anti-prismatic coordination geometry. The oxalate ligands are both chelating and bridging, and link Er(II) ions, forming Er-oxalate layers in which the attached water and 4-oxidopyridinium units point alternately up and down. A mirror plane passes through the Er atom, one C, the oxide O and two oxalate O atoms. The layers are assembled into a three-dimensional supra-molecular network via inter-molecular hydrogen bonding and π-π stacking inter-actions [centroid-centroid distances of 3.587 (2) Šbetween parallel pyridinium rings]. Both the water mol-ecule and the 4-oxidopyridinium ligand are disordered over two sites in a 1:1 ratio.

Poly[[diaqua-bis[µ-(2,4-dichloro-phen-oxy)acetato]calcium(II)] monohydrate].

In the title coordination polymer, {[Ca(C(8)H(5)Cl(2)O(3))(2)(H(2)O)(2)]·H(2)O}(n), the Ca(II) atom is eight-coordinated by six O atoms from four different (2,4-dichloro-phen-oxy)acetate ligands and two water mol-ecules, and displays a distorted square-anti-prismatic coordination geometry. The compound forms an infinite zigzag chain through connection of the metal centers by (2,4-dichlorphen-oxy)acetate ligands and hydrogen bonding of coordinated and inter-stitial water mol-ecules. These chains are further hydrogen bonded with neighboring chains, forming a supra-molecular network.

(2,2'-Bipyridyl-κN,N')tetra-kis(4-methyl-benzoato-κO)manganese(II).

In the title mononuclear complex, [Mn(C(8)H(7)O(2))(4)(C(10)H(8)N(2))], the Mn(II) atom lies on a twofold rotation axis and has a distorted octa-hedral coordination geometry defined by four O atoms from four 4-methyl-benzoate ligands and two N atoms from one 2,2'-bipyridyl ligand. The crystal structure is stabilized by inter-molecular hydrogen bonds and π-π stacking inter-actions [the centroid-centroid distance between the parallel pyridyl ring of a 2,2'-bipyridyl and benzene ring of a 4-methylbenzoic group of a neighboring complex is 3.839 (2) Å].

Erratum: Poly[aqua-(µ(2)-oxalato)(4-oxidopyri-din-ium)erbium(II)]. Corrigendum.

The chemical name in the title, the formula and the scheme of the paper by Gu, Hao, Song, Lin & Ma [Acta Cryst. (2008), E64, m649-m650] are corrected.[This corrects the article DOI: 10.1107/S1600536808009380.].

Diaqua-bis(4-methyl-benzoato-κO)zinc(II).

The Zn atom in the title mononuclear complex, [Zn(C(8)H(7)O(2))(2)(H(2)O)(2)], lies on a special position of site symmetry 2. The carboxyl-ate group binds in a monodentate manner so that the geometry is best described as tetra-hedral. Adjacent mol-ecules are linked by O-H⋯O hydrogen bonds into a three-dimensional network.