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Fermi's golden rule, a remarkable concept for the transition probability involving continuous states, is applicable to the interfacial electron-transporting efficiency via correlation with the surface density of states (SDOS). Yet, this concept has not been reported to tailor single-molecule junctions where gold is an overwhelmingly popular electrode material due to its superior amenability in regenerating molecular junctions. At the Fermi level, however, the SDOS of gold is small due to its fully filled d-shell. To increase the electron-transport efficiency, herein, gold electrodes are modified by a monolayer of platinum or palladium that bears partially filled d-shells and exhibits significant SDOS at the Fermi energy. An increase by 2-30 fold is found for single-molecule conductance of α,ω-hexanes bridged via common headgroups. The improved junction conductance is attributed to the electrode self-energy which involves a stronger coupling with the molecule and a larger SDOS participated by d-electrons at the electrode-molecule interfaces.

Porous materials for C2 H2 /CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low-cost, and easily scaled-up aluminum MOF (CAU-10-H) for highly efficient C2 H2 /CO2 separation. The suitable pore confinement in CAU-10-H can not only provide multipoint binding interactions with C2 H2 but also enable the dense packing of C2 H2 inside the pores. This material exhibits one of the highest C2 H2 storage densities of 392 g L-1 and highly selective adsorption of C2 H2 over CO2 at ambient conditions, achieved by a low C2 H2 adsorption enthalpy (27 kJ mol-1 ). Breakthrough experiments confirm its exceptional separation performance for C2 H2 /CO2 mixtures, affording both large C2 H2 uptake of 3.3 mmol g-1 and high separation factor of 3.4. CAU-10-H achieves the benchmark balance between separation performance, stability, and cost for C2 H2 /CO2 separation.

Twelve novel camphor sulfonamide derivatives 2a-2l were synthesized and characterized by

Imitation Switch (ISWI) chromatin remodelers are known to function in diverse multi-subunit complexes in yeast and animals. However, the constitution and function of ISWI complexes in Arabidopsis thaliana remain unclear. In this study, we identified forkhead-associated domain 2 (FHA2) as a plant-specific subunit of an ISWI chromatin-remodeling complex in Arabidopsis. By in vivo and in vitro analyses, we demonstrated that FHA2 directly binds to RLT1 and RLT2, two redundant subunits of the ISWI complex in Arabidopsis. The stamen filament is shorter in the fha2 and rlt1/2 mutants than in the wild type, whereas their pistil lengths are comparable. The shorter filament, which is due to reduced cell size, results in insufficient pollination and reduced fertility. The rlt1/2 mutant shows an early-flowering phenotype, whereas the phenotype is not shared by the fha2 mutant. Consistent with the functional specificity of FHA2, our RNA-seq analysis indicated that the fha2 mutant affects a subset of RLT1/2-regulated genes that does not include genes involved in the regulation of flowering time. This study demonstrates that FHA2 functions as a previously uncharacterized subunit of the Arabidopsis ISWI complex and is exclusively involved in regulating stamen development and plant fertility.

In order to find novel potential antifungal agrochemicals, a series of new 4-(1,2,4-oxadiazol-3-yl)-N-(4-phenoxyphenyl)benzamide derivatives 3a-j were designed, synthesized and characterized by their 1 H-, 13 C-NMR and HRMS spectra. The preliminary antifungal assay in vitro revealed that compounds 3a-j exhibited moderate to good antifungal activity against five plant pathogenic fungi. Especially, compound 3e presented significant antifungal activity against Alternaria solani, Botrytis cinerea and Sclerotinia sclerotiorum, superior to positive control boscalid. In the in vivo antifungal assay on tomato plants and cucumber leaves, compound 3e presented good inhibition rate against B. cinerea at 200 mg/L. Molecular dynamics simulation revealed that compound 3e could bind with the active site of class II histone deacetylase (HDAC).

Objectives Success in pregnancy in mammals predominantly depends on a well‐developed placenta. The differentiation of invasive trophoblasts is a fundamental process of placentation, the abnormalities of which are tightly associated with pregnancy disorders including preeclampsia (PE). Monoclonal nonspecific suppressor factor beta (MNSFβ) is an immunosuppressive factor. Its conventional knockout in mice induced embryonic lethality, whereas the underlying mechanism of MNSFβ in regulating placentation and pregnancy maintenance remains to be elucidated. Methods Trophoblast‐specific knockout of MNSFβ was generated using Cyp19‐Cre mice. In situ hybridization (ISH), haematoxylin and eosin (HE), immunohistochemistry (IHC) and immunofluorescence (IF) were performed to examine the distribution of MNSFβ and insulin‐like growth factor 2 mRNA‐binding protein 2 (IGF2BP2) at the foeto‐maternal interface. The interaction and expression of MNSFβ, IGF2BP2 and invasion‐related molecules were detected by immunoprecipitation (IP), immunoblotting and quantitative real‐time polymerase chain reaction (qRT‐PCR). The cell invasion ability was measured by the Transwell insert assay. Results We found that deficiency of MNSFβ in trophoblasts led to embryonic growth retardation by mid‐gestation and subsequent foetal loss, primarily shown as apparently limited trophoblast invasion. In vitro experiments in human trophoblasts demonstrated that the conjugation of MNSFβ with IGF2BP2 and thus the stabilization of IGF2BP2 essentially mediated the invasion‐promoting effect of MNSFβ. In the placentas from MNSFβ‐deficient mice and severe preeclamptic (PE) patients, downregulation of MNSFβ was evidently associated with the repressed IGF2BP2 expression. Conclusions The findings reveal the crucial role of MNSFβ in governing the trophoblast invasion and therefore foetal development, and add novel hints to reveal the placental pathology of PE., In placental mammals, the appropriate differentiation of placental trophoblast cell along the invasive pathway predominantly governs placentation and reproductive success. Here, we reveal the crucial role of MNSFβ in governing trophoblast cell invasion via interaction with IGF2BP2. Attenuated expression of placental MNSFβ and IGF2BP2 leads to limited trophoblastic invasiveness and pregnancy disorder including preeclampsia (PE).

An epidemic of an acute respiratory syndrome caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China, now known as coronavirus disease 2019 (COVID-19), beginning in December 2019, has attracted an intense amount of attention worldwide. As the natural history and variety of clinical presentations of this disease unfolds, extrapulmonary symptoms of COVID-19 have emerged, especially in the digestive system. While the respiratory mode of transmission is well known and is probably the principal mode of transmission of this disease, a possibility of the fecal-oral route of transmission has also emerged in various case series and clinical scenarios. In this review article, we summarize four different aspects in published studies to date: (a) gastrointestinal manifestations of COVID-19; (b) microbiological and virological investigations; (c) the role of fecal-oral transmission; and (d) prevention and control of SARS-CoV-2 infection in the digestive endoscopy room. A timely understanding of the relationship between the disease and the digestive system and implementing effective preventive measures are of great importance for a favorable outcome of the disease and can help climnicians to mitigate further transmission by taking appropriate measures.

BACKGROUND Serum ferritin (SF) test has been widely used in clinical practice. However, its reference intervals (RIs) vary depending on the analytical method and ethnic origin. This study was to establish the RIs using indirect method for SF in Chinese adults. METHODS SF was assayed on Abbott i2000SR analyzer. The SF test results of all health examinees (8913 males aged 18-93 years and 5397 females aged 18-90 years) between December 2010 and April 2019 were obtained from our laboratory information system. After Box-Cox transformation of raw data and exclusion of outliers, parametric and non-parametric approaches were used to calculate 95% RIs. The correlation between SF levels and ages, and the differences in SF levels between subgroups were also analyzed. RESULTS SF levels in females were significantly different from those in males (Z = 88.96, Z* = 23.17; Z > Z*) and showed a weak positive correlation with age (r = .466, P

BACKGROUND The use of thelytokous Wolbachia-infected Trichogramma (parasitic wasps) has long been considered as a way to enhance the efficacy of biocontrol. However, Wolbachia can affect the host physiology. We compared decision-making between bisexual and thelytokous Wolbachia-infected lines of Trichogramma dendrolimi Matsumura regarding behavior toward fresh and old eggs of Corcyra cephalonica at 25 ± 1 °C and 70 ± 5% relative humidity. RESULTS The behavioral patterns and sequences of the two lines were basically the same. The durations of various behavioral patterns and values of fitness indicators of the bisexual line on fresh eggs were generally significantly shorter and better, respectively, than on old eggs, whereas the thelytokous line behaved similarly toward the two types of eggs, and differences in most fitness indicators between fresh and old eggs were not significant. On fresh eggs, the durations of various behaviors in the bisexual line were generally significantly shorter than in the thelytokous line and the fitness indicators were generally significantly better. CONCLUSION Wolbachia affected the fitness of T. dendrolimi negatively. The potential of the thelytokous line as a biocontrol agent would not be as good as that of the bisexual line when decision-making only is considered. Therefore, further evaluations need to be carried out before the thelytokous line can be used in practical biocontrol. © 2018 Society of Chemical Industry

Background and objective Statins have been widely used in inflammatory diseases including asthma, because of their anti-inflammatory and immunomodulatory properties. It has been shown that simvastatin induces autophagy and cell death in some circumstances. However, the possible cross-talk between simvastatin and autophagic processes in lung disease is largely unknown. Thus, we investigated the impact of simvastatin on airway inflammation and airway remodelling and the possible relationship of these processes to a simvastatin-induced autophagic pathway in mouse models of asthma. Methods Ovalbumin (OVA)-sensitized and challenged mice were treated with simvastatin and sacrificed. The autophagy-related proteins Atg5, LC3B and Beclin1 were quantified, as well as the autophagy flux in bronchial smooth muscle cells (BSMCs). The relationship between airway inflammation and the autophagic process was investigated. Results We show that simvastatin treatment mediates activation of autophagy in BSMCs, which is correlated with airway inflammation and airway remodelling in mouse models of asthma. Simvastatin increases autophagy-related protein Atg5, LC3B and Beclin1 expression and autophagosome formation in lung tissue. Simvastatin-induced autophagy is associated with increased interferon-gamma (IFN-γ) and decreased IL-4, IL-5 and IL-13 cytokines production in BSMCs, as well as reversed extracellular matrix (ECM) deposition. In contrast, autophagy inhibitor 3-methyladenine (3-MA) eliminates the therapeutic effect of simvastatin. Conclusion These findings demonstrate that simvastatin inhibits airway inflammation and airway remodelling through an activated autophagic process in BSMCs. We propose a crucial function of autophagy in statin-based therapeutic approaches in asthma.

Ceritinib is a potent inhibitor of anaplastic lymphoma kinase (ALK), which has shown acceptable safety and substantial antitumor activity in ALK-positive non-small cell lung cancer (NSCLC) patients. Two food-effect studies were conducted in healthy adults to investigate the influence of food on the oral bioavailability of ceritinib: a study with low- or high-fat meals at 500 mg and a study with a light snack at 750 mg. Compared with the fasted state, AUC0-∞ (90%CI) of ceritinib was increased by 58% (34%, 86%) after the intake of a low-fat meal, by 73% (46%, 105%) after the intake of a high-fat meal, and by 54% (19%, 99%) after the intake of a light snack. Safety assessments also suggested that food may improve gastrointestinal (GI) tolerability after a single ceritinib dose. Based on the pharmacokinetic results, it is essential to avoid any type of meal during dosing of ceritinib because the intake of food may increase the occurrence of exposure-dependent, non-GI toxicities at the labeled dose of 750 mg daily during fasting. A randomized trial is ongoing to determine an alternative way to give ceritinib (450 mg or 600 mg with food) that may enhance GI tolerability in ALK-positive NSCLC patients.

This article proposes an erbium-doped fiber laser for remote fiber grating sensor system. Experimental results demonstrated that the sensitivity of wavelength of temperature tested from 25 to 85°C was 5 pm/°C and locating the proposed fiber sensor system 110 km away from the monitoring station ensured a high signal-to-noise ratio. The proposed fiber laser will facilitate the development of long-distance or large-scale fiber sensor systems and can be easily extended to multipoint sensing applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2809–2813, 2015

Two new chiral mononuclear Mn(III) complexes, [MnL(R)Cl (C2H5OH)]•C2H5OH () and [MnL(S) (CH3OH)2]Cl•CH3OH (), {H2L = (R,R)-or (S,S)-N,N’-bis-(2-hydroxy-1-naphthalidehydene)-cyclohexanediamine} were synthesized and characterized by various physicochemical techniques. Bond valence sum (BVS) calculations and the Jahn-Teller effect indicate that the Mn centers are in a +3 oxidation state. The statuses of the two complexes in the solution were confirmed as a pair of enantiomers by electrospray ionization, mass spectrometry (ESI-MS) spectrum. The binding ability of the complexes with calf thymus CT-DNA was investigated by spectroscopic and viscosity measurements. Both of the complexes could interact with CT-DNA via an intercalative mode with the order of (R-enantiomer) > (S-enantiomer). Under the physiological conditions, the two compounds exhibit efficient DNA cleavage activities without any external agent, which also follows the order of R-enantiomer > S-enantiomer. Interestingly, the concentration-dependent DNA cleavage experiments indicate an optimal concentration of 17.5 μM. In addition, the interaction of the compounds with bovine serum albumin (BSA) was also investigated, which indicated that the complexes could quench the intrinsic fluorescence of BSA by a static quenching mechanism. Chirality 27:142-150, 2015. © 2014 Wiley Periodicals, Inc.

Background Burn injury is one of the most common and devastating forms of trauma in daily life. However, the exact sequence of events after burn injury remains unknown. Objective This study aims to investigate gene expression alterations after burn injury. Methods Microarray data set GSE8056 was downloaded from the Gene Expression Omnibus (GEO) database, including 12 samples, equally distributed in four groups: normal skin tissue as control and damaged tissues 1–3 days after burn (early period); 4–7 days after burn (middle period); and more than 7 days after burn (late period). Packages in R language were utilized to pre-process the data and filter out the differentially expressed genes (DEGs). Functional annotation of all three groups of DEGs was conducted by using clusters of orthologous groups analysis. The DEGs shared by all three groups were picked out and analyzed with STRING to set up a protein–protein interaction network. CFinder was chosen to implement module analysis, and expression analysis systematic explorer was then adopted to reveal the dysfunctional pathways for each module. Results A total of 727, 782, and 445 DEGs were identified in the early, middle, and late period after burn, and 234 DEGs were identified as continually differentially expressed throughout all time periods, including genes encoding proinflammatory cytokines, such as interleukin (IL)-6, IL-8, and IL-1β, and genes associated with cell proliferation. Three modules associated with cell proliferation and inflammatory responses were generated from the protein–protein interaction network. Conclusion Our findings are beneficial for understanding the progression of the wound healing response after burn.

The coordination polymer [Cd(HL)(BPDA)]n·nH2O (1) based on 3-(5-(pyridin-4-yl)-1H-1,2,4-triazol-3-yl)pyridine (HL) and 1,1′-biphenyl-4,4′-dicarboxylic acid (H2BPDA) was hydrothermally synthesized and characterized by single-crystal X-ray diffraction, XRPD, IR spectroscopy, and elemental analysis. The asymmetric unit of compound 1 consists of one crystallographically independent CdII ion, one HL ligand, “two half” BPDA2– ligand, and one lattice water molecule. There are two crystallographically different BDPA2– moieties, but each of them is placed in a symmetry element. The BPDA2– ligands and CdII ions connected to2D sheet, and the 2D sheets are connected to a 3D MOF by the HL ligands. Each dimeric CdII unit links six nearest neighbors through the BPDA2– and HL ligands, and the dimeric CdII units are centrosymmetric. Two parallel HL ligands connect two dimeric CdII units, generating long Cd2–HL–Cd2–HL rings, also centrosymmetric. So we can define the dimeric CdII unit as a 6-connected node. Thus, the 3D structure can be described as a threefold parallel interpenetrated bsn beta-Sn topology. In addition, the optical properties of compound 1 and the free ligand HL were investigated.

A new coordination polymer, [Co2(L)2(4,4′-bipy)]n·3nH2O (1) based on 5-(3-methyl-5-phenyl-4H-1,2,4-triazol-4-yl)isophthalic acid (H2L) and 4,4′-bipyridine (4,4′-bipy) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, XRPD, IR, and elemental analysis. Temperature-dependent magnetic susceptibility and thermal degradation for 1 were also studied. The asymmetric unit of compound 1 consists of two crystallographically independent Co(II) ion, two L2− ligand, one 4,4′-bipy ligand, and three lattice water molecules. The 2D triangle networks were linked by the bridging 4,4′-bipy ligand to give rise to a 2-fold interpenetrated 3D architecture. The simplest cyclic motif of the 2D networks is a triangle ring consisting of three Co(II) cations and three L2− ligands. So we can define Co(II) ions as 4-connected nodes and the L2− ligands as 3-connected nodes. Thus, the 3D structure can be described as a 2-fold parallel interpenetrated ins InS 3,4-conn topology.

Three new mononuclear cobalt(II) complexes containing ligands with extended planar quinoxaline moieties, {dipyrido[3,2-a:2′,3′-c]phenazine (dppz) or dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq)}, viz. [Co(dppz)(acac)2] · CH3OH (1), [Co(dpq)(tfnb)2] (2) and [Co(dpq)(dbm)2] (3), where acac = acetylacetonate, tfnb = benzoyltrifluoroacetone and dbm = dibenzoylmethane, have been synthesized and structurally characterized as octahedral complexes. The binding ability of the complexes with calf thymus (CT)-DNA has been investigated by spectroscopic and viscosity measurements. Results indicate that all complexes bind to CT-DNA via intercalative mode, and the DNA binding affinity of dppz complex 1 is apparently stronger than that of dpq complexes 2 and 3. Furthermore, DNA photocleavage experiments indicate that these complexes are efficient DNA cleaving agents in UV-A (365 nm) and hydroxyl radical (HO·), singlet oxygen (1O2) and superoxide anion (1O2−) serve as the major cleavage active species. In addition, interaction of the complexes with bovine serum albumin (BSA) was investigated using UV − visible and fluorescence methods, which indicated that all complexes could quench the intrinsic fluorescence of BSA in a static quenching process. Copyright © 2014 John Wiley & Sons, Ltd.

Organic field-effect transistors were fabricated using a domain-ordered copper phthalocyanine (CuPc) thin film as the active layer prepared by weak epitaxial growth (WEG) technology. CuPc was deposited onto α-sexithiophene (α-6T) and α,ω-dihexylsexithiophene (α,ω-DH6T) films acting as the epitaxial substrate to realize the domain-order growth. As a result, the thin-film morphology of CuPc exhibits many re- gional domain-ordered structures measured by atomic force microscopy and X-ray diffraction. The field-effect mobilities are 0.11 and 0.085 cm2/Vs for the devices with CuPc/α-6T and CuPc/α,ω-DH6T, respectively. The threshold voltages were –7 V and –13 V for CuPc/α-6T and CuPc/α,ω-DH6T, respectively. The improved device performance could be attributed to the domain-order structure of the CuPc thin film. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Handling the (AFM) tip: The duration of stable molecular junctions was prolonged using a tactile feedback method in which the operator can sense the force of the AFM tip on the sample surface. The movement of the tip is adjusted accordingly, maintaining a more consistent current (i) and voltage (V), instead of having the tip move at a constant preset speed, as in the conventional setup.

A novel methodology that combines high performance liquid chromatography with photodiode-array detector (HPLC-DAD) coupled with second-order calibration method based on alternating trilinear decomposition (ATLD) algorithm was used in determination of the effective constituents such as costunolide and dehydrocostuslactone, in plasma sample and Chinese patent medicine Xiang Sha Yang Wei (XSYW) capsule. Complicated systems such as plasma and Chinese patent medicine which have intricate components are tedious to isolate and purify. The problem that chromatographic peaks are heavily overlapped among the analytes and interferents from the background matrices can be resolved, and the satisfactory quantification results have been gained with the help of the ATLD algorithm which utilized "mathematical separation" instead of partial "physical or chemical separation". Meanwhile, HPLC-MS/MS method was used to validate the accuracy of the proposed determination method.

According to the magnetic field data at 74 survey sites measured in the Philippines during 2001～2007,and using two methods of spherical cap harmonic and Taylor polynomial,we established magnetic field model on 2005.0 epoch for Philippines and the surrounding regions and got the distribution of the seven components of X,Y,Z,D,I,H,F.The distribution is similar in the two models,the difference is in the relief of inflection point and contour smoothness.At about 8°N,X,H,F have turning point and they are higher in west than in east.D,Y zero line extends approximately along latitude 8°N,the northern side of the line is negative and the southern part is positive,while the distribution of the contours is along the longitude direction, with minor variation along latitude direction.The distribution of Z and I is more regular,the zero-line is along 7.5°N,and the value is positive in northern region and negative in southern regions.The distribution patterns of the difference between the two models with the IGRF are very different,the value of spherical harmonic model minus IGRF model revealed a feature of alternative positive and negative anomalies,and the maximum positive and negative anomaly value of each component is in low latitudes.The anomaly distribution of Taylor minus IGRF is smoother.

As a basic technological product describing the geomagnetic spatial distribution, the national geomagnetic chart should choose an appropriate method to describe the geomagnetic field on standard epoch and its secular variations for the coming 5 years truly. We calculated the geomagnetic data at 1119 sites and 36 observatories in China by using the spherical cap harmonic (SCH) method, and obtained the space distribution of the normal and the anomalous geomagnetic fields in China for 2005.0 and the SCH model of geomagnetic secular variations in China for 2005~2010. The results showed that the errors of the geomagnetic field by IGRF could be ~ 5ʹ for the declination D and the inclination I and ~100 nT for the total intensity F. Because the geomagnetic survey data with new data and better resolution were used in the calculation, the geomagnetic chart for 2005.0 by the SCH method can better describe the space distribution of the geomagnetic field than the IGRF. This method can be stably used in compiling the China Geomagnetic Chart.

Two new complexes, {[Co(INAIP)·H2O]·2H2O}n (1), and {[Cu(INAIP)]·H2O}n (2) [H2INAIP = 5-(isonicotinamido)isophthalic acid] were synthesized under hydrothermal conditions, and characterized by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, and magnetic studies. In complex 1 both CoII atoms and INAIP2– ligands act as four-connected node, whereas in 2 both CuII atoms and INAIP2– ligands act as three-connected node.

(-)-Alternarlactam [(-)-1], a new promising cytotoxin against two human cancer cell lines, was isolated from an endophyte culture and synthesized (along with (+)-1) from readily available starting materials. The absolute configuration, chirality-activity relevance and self-aggregation of (-)-1 were assigned by a combination of synthetic, spectroscopic and computational approaches. The full characterization of the new fungal cytotoxin may provide valuable information in the discovery of new antitumor agents.

Using the data of the geomagnetic diurnal averages during 2000~2004 at 34 observatories in China, we calculated the mean annual change rates on the quiet days and all days, and the fitting annual change rates on the quiet days. The Taylor polynomial model and the spline model of the geomagnetic secular variation in China for epoch 2000.0~2005.0 were established based on the above annual change rates. The similarity and difference between the Taylor polynomial model, the spline model and the secular variation model of International Geomagnetic Reference Field (IGRF-SV) were analyzed and discussed. The results show that the shape and the value of the Taylor polynomial model and the spline model for the geomagnetic secular variation in China are quite consistent, and their long-term trends are also consistent with IGRF-SV. However, the geomagnetic secular variation in China has some regional characteristics.

Passive optical networks (PONs) offer a popular broadband access solution allowing for high bandwidth and long transmission range to meet user fast evolving needs. However, in certain applications, PON deployment cannot reach the end user, because geographic restrictions make fiber installation non-cost effective. Recently, hybrid fiber–wireless (FiWi) access networks have been proposed to combine the advantages of optical and wireless technologies and integrate them seamlessly. However, this integrated wired and wireless access network raises new security issues that need to be addressed. This paper reviews the architectures of currently proposed integrated access networks, proposes a new Worldwide Interoperability for Microwave Access (WiMAX) over Ethernet PON (EPON) architecture which achieves simplified and efficient system management. We present a unified security framework for the proposed architecture using Public Key Infrastructure (PKI). Through our analysis, we show that this security framework enhances the system security and realizes unified key management. Copyright © 2010 John Wiley & Sons, Ltd.

A novel 3D copper(I) coordination polymer [Cu8(ptim)8·3CH3CH2OH·2H2O] with the ligand 2,4,5-tri(4-pyridyl)-imidazole (Hptim) was synthesized and characterized. During the reaction, Hptim is oxidized by copper(II) and loses its hydrogen atom from the imidazole ring to add one coordination position. The novel complex has a 3D pillared double-layer network. The topological analysis of the crystal structure shows that the complex can be simplified to a 4-connected network with the Schlafli symbol (42,62,82). The novel complex shows remarkable thermal stability because of the neutral 3D polymeric structure. The investigation of its fluorescent property shows that the complex can induce fluorescence quenching of the ligand, which indicates that Hptim can act as a chemosensor for detecting Cu+ ions in high selectivity.

Four novel 2D complexes M2(Hptim)2(HBTC)2 [M = Co (1), Cd (2), Zn (3), Mn (4); Hptim = 2,4,5-tri(4-pyridyl)-imidazole; HBTC2– = Benzene-1,3,5-tricarboxylic acid] were synthesized under solvothermal conditions. The four complexes are isomorphous and present a unique structure with a 1D ladder of [Co2(HBTC)2]n. The 2D network structure of 1 is achieved through bridging Hptim groups, which coordinate to the metal atoms of two adjacent 1D [Co2(HBTC)2]n ladders. Magnetic measurements reveal that dominant antiferromagnetic coupling was observed in compounds 1 and 4. Compounds 2 and 3 both exhibit strong fluorescent emissions in the solid state and may be suitable candidates for fluorescent materials.

Two novel 1,2,4-triazole-based copper(II) complexes have been synthesized and structurally characterized by X-ray crystallography: [Cu2LCl3]·0.5[CuCl4]·EtOH (1) and [Cu2LBr3]·Br·H2O (2) (L = 3,5-bis{[bis(2-methoxyethyl)amino]methyl}-4H-1,2,4-triazol-4-amine). Single-crystal diffraction reveals that the two Cu atoms have a distorted octahedral geometry for 2, but one Cu atom is in a distorted square-pyramidal environment and the other one is in a distorted octahedral environment for 1 because of the different bridged halogen atoms. The interactions of the two complexes with calf thymus DNA (CT-DNA) have been investigated by UV absorption, fluorescence spectroscopy, circular dichroism spectroscopy, viscosity measurements and cyclic voltammetry. The apparent binding constant (Kapp) values for complexes 1 and 2 are 2.98 × 106 and 4.05 × 106M–1. Furthermore, both the compounds display efficient oxidative cleavage of supercoiled DNA in the presence of external agents. The rate constants for the conversions of supercoiled to nicked DNA are 4.38 × 10–4 s–1 (for 1) and 5.26 × 10–4 s–1 (for 2). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2010)

A cyclic-tetranuclear [Ni4(H–1L)2(μ-PhCOO)2(H2O)4](ClO4)4·2H2O (1) complex has been prepared by reaction of nickel (II) perchlorate with L (L = 3,5-bis((bis(2-hydroxylethyl)amino)methyl)-4H-1,2,4,-triazol-4-amine) and benzoate sodium. The X-ray structure shows that complex 1 consists of a cyclic tetranuclear nickel(II) cation and four uncoordinated ClO4– anions and two crystalline water molecules, in which four nickel atoms have distorted octahedral coordination. Magnetic studies indicate the existence of antiferromagnetic coupling between the nickel(II) ions. The interaction of the complex with calf thymus DNA (CT-DNA) has been investigated by UV absorption and fluorescent spectroscopy, furthermore, DNA cleavage experiments show that the complex cleavages DNA through an oxidative mechanism.