In situ generated 2,5-pyrazinedicarboxylate and oxalate ligands leading to a Eu-MOF for selective capture of C2H2 from C2H2/CO2.

The separation of C2H2/CO2 mixtures is a very important but highly challenging task due to their comparable physical natures and relative sizes. Herein, we report a europium-based 3D microporous MOF with a 4-connected two-nodal net with {4·53·62}2{42·62·82} topology, {[Eu2(pzdc)(ox)2(H2O)4]·5H2O}n (1) (H2pzdc = 2,5-pyrazinedicarboxylic acid, H2ox = oxalic acid), prepared by a hydrothermal method involving in situ generation of 2,5-pyrazinedicarboxylate and oxalate ligands. Two different temperatures were utilized to create two porous materials (1a and 1b) with channels of 4.8 × 5.4 Å and 4.1 × 6.3 Å, and 4.8 × 5.4 and 4.6 × 8.7 Å2, respectively. 1b shows a superior ability to selectively capture C2H2 from C2H2/CO2 as compared with 1a. At 1 bar and 298 K, 1b takes up 4.10 mmol g-1 C2H2 and 1.84 mmol g-1 CO2, respectively. In addition, at 298 K and 1 bar, 1b has a high selectivity for C2H2 over CO2, with an IAST selectivity of 12.7 while the value for 1a is 3.2. The separation of C2H2/CO2 with 1b also exhibits good reusability.

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 Novel Flower-Like Ag/AgCl/BiOCOOH Ternary Heterojunction Photocatalyst: Facile Construction and Its Superior Photocatalytic Performance for the Removal of Toxic Pollutants.

Novel 3D flower-like Ag/AgCl/BiOCOOH ternary heterojunction photocatalysts were fabricated by the solvothermal and in-situ precipitation methods, followed by light reduction treatment. The Ag/AgCl nanoparticles were homogeneously distributed on 3D BiOCOOH microspheres. These obtained catalysts were characterized by XRD, SEM, TEM, diffuse reflectance spectra (DRS), and photoluminescence (PL). As expected, they exhibited extraordinary photocatalytic capabilities for the elimination of rhodamine B (RhB) and ciprofloxacin (CIP) under simulated sunlight, the results revealed that the Ag/AgCl/BiOCH-3 with 20 wt.% of Ag/AgCl possessed the maximum activity, and the rate constant for the RhB degradation reached up to 0.1353 min-1, which was about 16.5 or 12.2 times that of bare BiOCOOH or Ag/AgCl. The PL characterization further verified that Ag/AgCl/BiOCOOH heterojunctions were endowed with the effective separation of photogenerated carriers. The excellent photocatalytic ability of Ag/AgCl/BiOCOOH could be credited to the synergistic interactions between Ag/AgCl and BiOCOOH, which not only substantially widened the light absorption, but also evidently hindered the charge recombination. The trapping experiments revealed that the dominant reactive species in RhB removal were h+, •OH, and •O2- species. In addition, Ag/AgCl/BiOCOOH was quite stable and easily recyclable after multiple cycles. The above results imply that the 3D flower-like Ag/AgCl/BiOCOOH ternary heterojunction photocatalyst holds promising prospects in treating industrial wastewater.

Field-induced slow magnetic relaxation in two-dimensional and three-dimensional Co(ii) coordination polymers.

Two coordination polymers formulated as [Co(1,4-bimb)0.5(5-aip)(H2O)]n (1) and [Co(1,4-bib)1.5(5-hip)(H2O)]n (2) (1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 5-aip = 5-aminoisophthalic acid, 1,4-bib = 1,4-bis(1-imidazolyl)benzene and 5-hip = 5-hydroxyisophthalic acid) have been prepared and structurally characterized. Complex 1 is a two-dimensional (2D) network where Co(ii) is six coordinate in a CoO4N2 coordination environment, while the structure of 2 consists of a three-dimensional (3D) framework built from mononuclear Co(ii) units with distorted octahedral geometry as nodes. Static magnetic studies show that first-order orbital angular momentum may play an important role in the magnetic properties of 1, whereas strong easy-axis anisotropy (D = -102 cm-1) was observed in 2. Alternating current (ac) susceptibility measurements demonstrate that both the complexes display field-induced single ion magnet (SIM) behavior.

Temperature tuned syntheses of two new d10-based Cd(ii) cluster metal-organic frameworks: luminescence sensing and photocatalytic properties.

The solvothermal reactions of 5,5'-(1,4-phenylenebis(methyleneoxy))diisophthalic acid (H4L) and the N-donor ancillary ligand 3,3',5,5'-tetramethyl-4,4'-bipyrazole (bpz) with cadmium(ii) salts at two different reaction temperatures yielded two new metal-organic frameworks (MOFs), viz., [Cd(H2L)(bpz)] n (1) and [Cd2(H4L)(L)(bpz)2] n (2), which have been characterized by FTIR and single crystal X-ray diffraction. The single crystal X-ray diffraction studies revealed that 1 displays a 3-periodic network with monometallic SBU, while 2 exhibits a 3-periodic network with a 2-fold interpenetration feature. The effects of variation in reaction temperature on the architecture of MOFs 1 and 2 have been discussed. The luminescence investigation indicates that both 1 and 2 displayed good turn-off luminescence sensing against nitroaromatic compounds (NACs), especially m-nitrophenol (MNP), via a decrease in their luminescence intensities with a K sv value of 6.43 × 103 for 1 and 2.03 × 104 for 2 and LOD values of 1.09 and 0.81 ppm for 1 and 2, respectively. The plausible mechanism for the decline in luminescence intensity of the MOFs with NACs has been addressed using theoretical calculations. The photocatalytic properties for both the MOFs demonstrated that they display efficient photocatalytic performances to degrade methyl violet (MV) under UV irradiation. The plausible mechanism through which these MOFs exhibited photocatalytic properties has been suggested using band gap calculations.

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.

Identification of bioactive metabolites dihydrocanadensolide, Kojic acid, and vanillic acid in soy sauce using GC-MS, NMR spectroscopy, and single-crystal X-ray diffraction.

Microbial transformations of intrinsic substrates offer immense potential for generating new bioactive compounds in fermented food products. The aim of this work was to characterize the secondary metabolites in soy sauce, one of the oldest fermented condiments. Ethyl acetate extract (EAE) of soy sauce was separated using flash column chromatography, crystallized, and analyzed by nuclear magnetic resonance (NMR), single-crystal X-ray diffraction (SC-XRD), and mass spectroscopy. Dihydrocanadensolide (DHC), an antiulcer agent, was identified in a food for the first time. The natural stereostructure of DHC, which remained controversial for several decades, was determined as (3S,3aS,6R,6aR)-6-butyl-3-methyltetrahydrofuro[3,4-b]furan-2,4-dione using SC-XRD analysis. Kojic acid (KA) and vanillic acid (VA) were also identified from EAE as bioactive metabolic products of fungi and yeasts. Moreover, a new polymorphic form of KA was determined by SC-XRD.

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.

A microporous, moisture-stable, and amine-functionalized metal-organic framework for highly selective separation of CO2 from CH4.

A new microporous amino-functionalized metal-organic framework has been synthesized by direct self-assembly, which exhibits high moisture-stability, acceptable capacity, and unprecedented high selectivity for CO(2) over CH(4), suggesting its potential application in gas separation processes like natural gas and biogas upgrading.

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].

Tuning the moisture stability of metal-organic frameworks by incorporating hydrophobic functional groups at different positions of ligands.

The introduction of hydrophobic groups (e.g. methyl) at the most adjacent sites of each and every coordinating nitrogen atom of the bipyridine pillar linker in a carboxylate-based bridging MOF could shield the metal ions from attack by water molecules, and thus enhance the water resistance of the MOF structure significantly.

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.