Selective oxidation of β-keto ester modulated by the d-band centers in D-A conjugated microporous metallaphotoredox catalysts containing M-salen (MZn, Cu and Co) and triazine monomers.

Photocatalytic selective oxidation plays an important role in developing green chemistry. However, it is challenging to design an efficient photocatalyst for controlling the selectivity of photocatalytic oxidation reaction and exploring its detailed mechanism. Here, we synthesized three conjugated microporous polymers (CMPs) with D-A structures, named M-SATE-CMPs (MZn, Cu and Co), with different d-band centers based on different metal centers, resulting in the discrepancy in adsorption and activation capacities for the reactants, which produces the selectivity of β-keto esters being catalyzed into α-hydroperoxide β-keto esters (ROOH) or to α-hydroxyl β-keto esters (ROH).

Self-Assembly of an Anionic [CuI] Supramolecular Cluster Driven by Ion-Pair Interaction and Catalytic Properties.

The rational design and controlling synthesis of an anionic cuprous iodide supramolecular cluster with high nuclearity through noncovalent interactions remains a significant challenge. Herein, a cationic organic ligand () was driven by anion-cation ion-pair electrostatic interaction to induce free cuprous iodide to aggregate into an anionic supramolecular cluster, [(CuI)()] (). Moreover, five copper(I) atoms bind with eight iodides through multiply bridged Cu-I bonds associated with intramolecular cuprophilic interactions in this butterfly-shaped cluster core.

A linker conformation induced metal-organic framework with high stability and efficient upgrading of natural gas.

Natural gas plays an important role in daily life and the petrochemical industry, but there are often large amounts of impurities which prevent the full use of methane in natural gas. Developing excellent adsorbents to purify CH from multi-component mixtures is crucial, but also faces great challenges. Here, by utilizing a ligand conformation preorganization strategy, we employ a flexible nonplanar hexacarboxylate ligand with 2 symmetry to successfully construct a robust microporous metal-organic framework {[Cu(bmipia)(HO)]·(DMF)(CHCN)} (GNU-1, bmipia = 5-[,-bis(5-methylisophthalic acid)amion] isophthalate) with an unprecedented topology.

A Nanocluster [AgCl(SPhBu)]: Chloride Intercalation, Specific Electronic State, and Superstability.

The controlling synthesis of novel nanoclusters of noble metals (Au, Ag) and the determination of their atomically precise structures provide opportunities for investigating their specific properties and applications. Here we report a novel silver nanocluster [AgCl(SPhBu)] (Ag) whose structure is determined by X-ray single crystal diffraction. The structure analysis shows that nanocluster Ag contains a Ag core, a surface shell of [AgClS], and a Cl intermediate layer located between Ag and [AgClS].

Bisphosphine-Stabilized Gold Nanoclusters with the Crown/Birdcage-Shaped Au Cores: Structures and Optical Properties.

To estimate the effect of bisphosphine ligands on the formation of the isomeric core structures of gold nanoclusters, the different ligation of bisphosphine ligands is usually used to participate in the construction of gold nanoclusters. Here, the selection of the different bisphosphine ligands, DPEphos and Xantphos, is performed to construct two novel gold nanoclusters, [Au(DPEphos)Cl]Cl () and [Au(Xantphos)Cl]Cl(), which have been characterized by IR, H and P NMR, ESI-MS, XRD, SEM, XPS, TG, UV-vis, and X-ray crystal structure analysis. The structural analyses indicate that the ligation of bisphosphine ligands play a crucial role in the formation of the fascinating Au cores: gold nanocluster includes a birdcage-shaped Au core with eight electrons, while gold nanocluster contains a crown-shaped Au core with eight electrons.

[Ag(N-triphos)(Cl)](NO): a stable Ag-P superatom with eight electrons (N-triphos = tris((diphenylphosphino)methyl)amine).

A first and stable Ag-P superatom nanocluster [Ag(N-triphos)(Cl)](NO) (1) has been successfully synthesized and characterized. X-ray analysis shows that this Ag cluster has a hexacapped body-centered cubic (bcc) framework which is consolidated by four tripodal N-triphos ligands. The identity of 1 is confirmed by high resolution ESI-MS.

Rare double spin canting antiferromagnetic behaviours in a [Co24] cluster.

A fish-basket-shaped [Co24] cluster, [Co24(μ3-O)4(ampc)4(μ3-OH)4(μ2-OH)4(NO3)5(HCO2)22(H2O)10]·[(HCO2)·2(CH3OH)·x(H2O)], was woven by bridging oxygen atoms from O(2-), OH(-), NO3(-) and HCO2(-) groups, and stabilized terminally by a semi-rigid organic ligand 4',4'-[(dimethylamino)dimethylene]-bis[(1,1'-biphenyl)-2-carboxylate] (ampc(-)). Magnetic analyses indicate that the [Co24] cluster exhibits two types of spin canting orders, spin flop and a small hysteresis with a coercive field of ca. 661 Oe and a remanent magnetization of 0.

Aggregation of the metallocycles {Cu8} and {Cu20} using [Cu(bp)] units (H2bp = bis(2-hydroxybenzyl)amine): structures and magnetic properties.

Two metallocycles, {Cu8(bp)4(OH)4(H2O)4(ClO4)4} (1) and {Cu20(bp)20} (2), were afforded by the reactions of the semi-flexible tridentate ligand bis(2-hydroxybenzyl)amine (H2bp) with Cu(ClO4)2·6H2O and Cu(OAc)2·H2O. Complex 1 has a saddle-shaped cyclic structure and complex 2 has a nanosized wheel-shaped structure. The two compounds consist of [Cu(bp)] units.

Molecular Epidemiological Investigation of Thalassemia in the Chengdu Region, Sichuan Province, Southwest China.

Thalassemia is the most common inherited disease in southern China. However, this disorder is usually ignored by the health system in the Sichuan Province due to the lack of epidemiological data. To provide basic epidemiological data for thalassemia screening, genetic counseling, and prenatal diagnosis (PND) in the Chengdu region, a total of 3262 healthy subjects were assessed by complete blood count (CBC), reverse dot-blot gene chip, gap-polymerase chain reaction (gap-PCR), and PCR-DNA sequencing.

One-dimensional Cu(I) and Ag(I) ladder-like coordination polymers supported by 2-ethyl-1-(pyridin-3-ylmethyl)-1H-benzimidazole.

The title complexes, poly[[bis[μ2-2-ethyl-1-(pyridin-3-ylmethyl)-1H-benzimidazole-κ(2)N(1):N(3)]copper(I)] tetrafluoroborate acetonitrile monosolvate], {[Cu(C15H15N3)2]BF4·CH3CN}n, (I), and poly[[bis[μ2-2-ethyl-1-(pyridin-3-ylmethyl)-1H-benzimidazole-κ(2)N(1):N(3)]silver(I)] perchlorate methanol monosolvate], {[Ag(C15H15N3)2]ClO4·CH3OH}n, (II), are isostructural and exhibit one-dimensional ladder-like structures in which each asymmetric unit contains one metal ion (Cu(+) or Ag(+)), two 2-ethyl-1-(pyridin-3-ylmethyl)-1H-benzimidazole (bep) ligands, one counter-anion (tetrafluoroborate or perchlorate) and one interstitial molecule (acetonitrile or methanol). Each metal ion exhibits a distorted tetrahedral coordination geometry consisting of two pyridyl and two benzimidazole N atoms from four distinct ligands. Two metal ions are linked by two bep ligands to form a centrosymmetric 18-membered M2(bep)2 metallacycle, while adjacent M2(bep)2 metallacycles are further interlinked by another two bep ligands resulting in a ladder-like array.

Nanospheric [M20(OH)12(maleate)12(Me2NH)12]4+ clusters (M = Co, Ni) with O(h) symmetry.

Nanospheric hydroxo-bridged clusters of [M(20)(OH)(12)(maleate)(12)(Me(2)NH)(12)](BF(4))(3)(OH)·nH(2)O (M = Co (1), Ni (2)) with O(h) symmetry were afforded under hydrothermal condition with Co(BF(4))(2)·6H(2)O/Ni(BF(4))(2)·6H(2)O and fumaric acid in a DMF/EtOH mixed solvent. They are characterized by elemental analysis, IR, and X-ray diffraction. X-ray single crystal diffraction analyses show that these two complexes are isostructural containing an ideally cubic M(8) core in that each two M atoms are doubly bridged at the edges by one OH(-) and one maleate, while these OH(-) and maleate groups are coordinated further by exterior identical 12 M atoms which construct a perfect M(12) icosahedron to encapsulate the cubic core.

Synthesis, structural characterization and luminescent properties of a series of Cu(I) complexes based on polyphosphine ligands.

A series of Cu(I) complexes with a [Cu(NN)(PP)](+) moiety, [Cu(phen)(pba)](BF(4)) (1a), [Cu(2)(phen)(2)(pbaa)](BF(4))(2) (2a), [Cu(2)(phen)(2)(pnaa)](BF(4))(2) (3a), [Cu(2)(phen)(2)(pbbaa)](BF(4))(2) (4a), [Cu(dmp)(pba)](BF(4)) (1b), [Cu(2)(dmp)(2)(pbaa)](BF(4))(2) (2b), [Cu(2)(dmp)(2)(pnaa)](BF(4))(2) (3b) and [Cu(2)(dmp)(2)(pbbaa)](BF(4))(2) (4b) (phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, pba = N,N-bis((diphenylphosphino)methyl)benzenamine, pbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)benzene-1,4-diamine, pnaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)naphthalene-1,5-diamine and pbbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)biphenyl-4,4'-diamine), were rationally designed and synthesized. These complexes were characterized by (1)H and (31)P NMR, electrospray mass spectrometry, elemental analysis and X-ray crystal structure analysis. Introduction of different central arene spacers (phenyl, naphthyl, biphenyl) into ligands, resulting in the size variation of these complexes, aims to tune the photophysical properties of the complexes.

[μ-N,N'-Bis(diphenyl-phosphinometh-yl)benzene-1,4-diamine-κP:P']bis-[(2,2'-bipyridine-κN,N')silver(I)] bis-(per-chlorate) acetone disolvate.

The title complex, [Ag(2)(C(10)H(8)N(2))(2)(C(32)H(30)N(2)P(2))](ClO(4))(2)·2CH(3)COCH(3), is a centrosymmetric dimer with pairs of Ag(I) atoms bridged by N,N'-bis-(diphenyl-phosphinometh-yl)ben-zene-1,4-diamine ligands. In addition, each Ag(I) atom is coordin-ated by one chelating 2,2'-bipyridine ligand, giving a distorted trigonal coordination environment.

{4-[(Diphenyl-phosphino)methyl-amino]pyridinium-κP}bis-(nitrato-κO)silver(I).

In the title mononuclear complex, [Ag(C(18)H(18)N(2)P)(NO(3))(2)], the metal centre is coordinated in a slightly distorted trigonal-planar geometry by the P atom of the phosphine ligand and the O atoms of the two monodentate nitrate anions. In the crystal structure, complex mol-ecules are connected by inter-molecular N-H⋯O hydrogen bonds, forming chains running parallel to the b axis.

{μ-trans-N,N'-Bis[(diphenyl-phosphan-yl)meth-yl]benzene-1,4-diamine-κP:P'}bis-{(acetonitrile-κN)[dipyrido[3,2-a:2',3'-c]phenazine-κN,N]copper(I)} bis-(tetra-fluoridoborate).

In the centrosymmetric dinuclear title compound, [Cu(2)(C(2)H(3)N)(2)(C(18)H(10)N(4))(2)(C(32)H(30)N(2)P(2))](BF(4))(2), the Cu(I) centre is coordinated by two N atoms from a dipyridophenazine ligand, one P atom from an N,N'-bis-[(diphenyl-phosphan-yl)meth-yl]benzene-1,4-diamine (bpbda) ligand, and one N atom from an acetonitrile mol-ecule in a distorted tetra-hedral geometry. The bpbda ligand, lying on an inversion center, bridges two Cu(I) centres into a Z-shaped complex. Intra-molecular π-π inter-actions between the dipyridophenazine ligand and the benzene ring of the bpbda ligand are observed [centroid-centroid distance = 3.

A coordination polymer of CdCl2 with the novel zwitterionic dicarboxylate ligand 2,2'-(2-methylbenzimidazolium-1,3-diyl)diacetate (pda).

The title compound, poly[chlorido[mu(4)-2,2'-(2-methylbenzimidazolium-1,3-diyl)diacetato]cadmium(II)], [Cd(C(12)H(11)N(2)O(4))Cl](n), is an undulating two-dimensional polymer consisting of a paddlewheel Cd(2)(CO(2))(4) cluster which lies on an inversion centre. These paddlewheel clusters act as four-connected square building units interlinked via bridging zwitterionic dicarboxylate ligands into a corrugated layer which is consolidated by pi-pi interactions between benzene rings of benzimidazole groups. Neighbouring layers are further assembled via interlayer pi-pi interactions into a three-dimensional supramolecular structure.

[The mechanism of accumulative oxidative injury by hydrogen peroxide on human retinal pigment epithelial cells].

Objective: To explore the effects of oxidative injury induced by hydrogen peroxide on human retinal pigment epithelial (RPE) cells.

Methods: Cultured human RPE cells were treated by 600 micromol/L hydrogen peroxide (H2O2) for 1, 6, 12, 24 and 72 hours. Cell viability was assessed by the MTT assay.

[Sequence analysis of the HA1 regions of hemagglutinin genes of influenza viruses (H3N2) isolated from children in Beijing from 1998 - 2004].

Objective: To characterize the HA1 regions of hemagglutinin gene of influenza viruses (H3N2) isolated from children in Beijing from 1998 - 2004.

Methods: The HA1 regions of hemagglutinin gene were amplified by RT-PCR from the viruses isolated and identified as A3 (H3N2) from clinical samples collected from infants and children during the peak seasons of influenza between 1998 and 2004. PCR products were sequenced or cloned into T-A vector and were analyzed after being sequenced.

[The protective effect of hypoxic preconditioning against light-induced photoreceptor degeneration in mice].

Objective: To study the protective roles of hypoxic preconditioning in light induced retinal injury in a mice model and investigate the possible mechanism of related gene regulation.

Methods: 54 BALB/c mice were randomly divided into simple light exposure group (SL), hypoxic pretreatment group (HP) and control group (CON). The mice of SL and HP were continually exposed to light for 3 h, which built model of light-induced damage.

[Application of molecular biological techniques in the surveillance of influenza viruses in infants and young children].

Objective: To establish a rapid, specific and effective technique for identifying subtyping A(1), A(3) and B of influenza virus isolates and clinical specimens as well as to analyze the sequences of nucleotides and deduced amino acids of HA1 regions from isolates of influenza virus A(3) isolated from 1996 to 2002.

Methods: Six inner and outer sets of oligonucleotide primers were designed to detect, type and subtype human influenza A and B. The first two corresponding sets differentiate type A and B of matrix (M) gene while, the second two corresponding sets identify the H(1) and H(3) subtypes of type A virus HA gene.

Effects of a bioartificial liver support system on acetaminophen induced acute liver failure canines.

AIM:To evaluate the safety and efficacy of the bioartificial liver support system in canines with acute liver failure (ALF).METHODS:Nine canines with acute liver failure by acetaminophen-induced received TECA-I bioartificial liver support system (BALSS) from Hong Kong TECA LTD Co. Blood was perfused through a hollow fiber tube containing (1-2)X10(10) the porcine hepatocytes.