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A hexagonal prismatic Cu6S6 cluster exhibits excellent near-infrared fluorescence properties due to its short Cu–Cu bonds, however, the construction of Cu6S6 cluster-based compounds with extended structures is still a challenge. Here, four new Cu6S6 cluster-based coordination compounds, formulated as Cu3(pymt)3 (1), {(CuCN)2[Cu3(mpymt)3]}n (2), {(CuSCN)[Cu3(mpymt)3]}n (3) and {(CuCN)2[Cu3(dmpymt)3]·CH3CN}n (4) (Hpymt = pyrimidine-2-thiolate, Hmpymt = 4-methyl-pyrimidine-2-thione and Hdmpymt = 4,6-dimethylpyrimidine-2-thione), have been synthesized through the reactions of mercaptopyrimidine derivatives and CuCN or CuSCN under solvo-thermal conditions and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, IR spectroscopy, elemental analysis, and thermal gravimetric analysis. Single-crystal X-ray diffraction analysis reveals that compound 1 is a zero-dimensional Cu6(pymt)6 molecule containing a distorted pseudo-hexagonal prismatic Cu6S6 core. Compounds 2 and 4 with isomorphic frameworks but different organic linkers show a rare three-dimensional framework with nor topology constructed from Cu6(mpymt)6 units and one-dimensional chiral [Cu(CN)]n chains; compared with compound 2, a more hydrophobic one-dimensional channel in compound 4 is observed due to the increase of the methyl groups on the pyrimidine ligand, in which acetonitrile molecules are filled in the channels of compound 4. Compound 3 shows a rare two-dimensional layer constructed from Cu6(mpymt)6 units and one-dimensional puckered (CuSCN)n chains. For the first time, Cu6S6 clusters are connected to one-dimensional inorganic CuCN (or CuSCN) chains through mercaptopyrimidine derivatives to obtain extended arrays in compounds 2–4. The crystals of compounds 1–4 in the solid state all show apparent red light emission. Compound 4 shows sensitive luminescence quenching response to nitrobenzene (NB), and the corresponding quenching constant (Ksv) and detection limit are 2.06 × 103 M−1 and 9.27 ppm, respectively. This study provides a new strategy to construct Cu6S6 cluster-based coordination polymers that have great potential in various applications such as luminescence sensing.

Hypoxia-induced chemotherapy resistance is the main hindrance for solid tumor treatment. Hypoxia inducible factor-1α (HIF1α), an adaptive gene of hypoxia condition, played an important role in affecting chemotherapy sensitivity for many cancer types and various therapeutic regimens. This study focused on the impact of HIF1α on predicting response and survival of taxane-based neoadjuvant therapy (NAT) for breast cancer (BC) patients and the concrete mechanism that HIF1α mediated paclitaxel chemo-insensitivity. We evaluated HIF1α expression immunohistochemically from biopsies of 108 BC patients receiving paclitaxel–cisplatin NAT. Univariate and multivariate logistic regression analysis revealed that high HIF1α expression led to lower rate of pathological complete response (pCR) and worse prognosis. Analysis of GEO datasets also indicated negative association between HIF1α expression and response of taxane-based NAT in BC patients. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of differential expression genes (DEGs) in different HIF1α expression groups from TCGA database showed that HIF1α participated in interleukin 17 (IL-17) signaling pathway. Correlation analysis suggested that HIF1α was positively related to the IL-17 pathway. CXC motif chemokine ligand 10 (CXCL10) was the only DEG in the IL-17 pathway inversely relating to NAT response. Experiments in vitro verified that HIF1α/IL-17 pathway influences paclitaxel sensitivity to BC cells. Correlation analysis between HIF1α/IL-17A/CXCL10 and infiltration of immune cells in BC uncovered that high expression of all the above three genes were positively correlated to neutrophil infiltration in BC. Collectively, our findings shed novel insight into the mechanism of chemotherapy resistance and implied that HIF1α inhibitor may be a promising drug combined with traditional chemotherapeutic drug to increase the chemotherapy efficacy.

Emerging data indicate that prenatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) could interfere with myogenic differentiation in vivo. Acetylcholinesterase (EC3.1.1.7; AChE), an enzyme critical for cholinergic neurotransmission, is abundantly expressed in neurons and mature myotubes, and we recently found that muscle AChE expression was suppressed in parallel with the inhibition of myogenic differentiation upon TCDD treatment in mouse C2C12 cells. This TCDD-induced suppression of muscle AChE was proposed to involve an aryl hydrocarbon receptor (AhR)-independent mechanism, but the precise underlying mechanism remains unclear. Considering the widely recognized role of muscular activity in AChE expression and its potential crosstalk with the AhR signaling pathway, we sought to investigate the effect of TCDD on muscle AChE expression in the presence of muscular activity. Therefore, we employed a highly contractile rat primary skeletal muscle culture system in which AChE activity and the expression of genes related to it (AChE T subunit and collagen Q (ColQ)) were increased during the myogenic differentiation process. Although TCDD treatment successfully induced the expression of genes regulated by AhR activation, the treatment exerted no notable effects on myogenic differentiation. Moreover, muscle AChE enzymatic activity and mRNA level remained unchanged following TCDD treatment, and only ColQ mRNA expression was slightly increased after 4-day treatment with TCDD (10−10 M). The compensatory role of muscle-contraction-related signaling pathways in this newly identified unresponsiveness of muscle AChE to TCDD warrants further investigation.

Type 3 innate lymphoid cells (ILC3s) are distributed in the gut and regulate inflammation by secreting cytokines, including interferon (IFN)-γ and interleukin (IL)-17. The maintenance and function of ILC3s involve the activity of aryl hydrocarbon receptor (AhR), a potent ligand of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), one of the most toxic dioxin congeners. Thus, TCDD exposure might affect ILC3s. To obtain in vivo evidence supporting this notion, we exposed female C57BL/6 mice orally to TCDD (low/high doses: 0.1/10 μg/kg body weight) during pregnancy and lactation periods, and after the exposure, evaluated the mothers and offspring for alterations in ILC3 differentiation and function in the colon. ILC3 frequency among colonic lamina propria lymphocytes was preferentially diminished in the offspring, and, in parallel, the median fluorescence intensity (MFI) of retinoic acid receptor-related orphan receptor (ROR)γt, which is associated with ILC3 differentiation, was also decreased in ILC3s. Conversely, the percentages of two subsets of the cells, one positive for natural cytotoxicity receptor NKp46 and the other for IL-17a, were increased in TCDD-exposed mothers and offspring. Moreover, the percentage of IFN-γ+ ILC3s was increased specifically in the mothers, but this was in conjunction with a significant decrease in the MFI of IFN-γ, which suggests that the IFN-γ+ ILC3 subset was functionally altered. In conclusion, maternal exposure to TCDD suppresses ILC3 differentiation in the offspring and influences ILC3 function in distinct manners in the mother and offspring. Our study provides new insights into the intergenerational interference of dioxins in colonic ILC3s.

Emerging evidence showed that 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) could induce expression of certain reactivation-associated genes in astrocytes, however, the consequent cellular effects and molecular mechanisms are still unclear. During the process of astrocyte reactivation, migration is a critical cellular event. In the present study, we employed wound-healing assay and Transwell® motility assay to explore the effects of TCDD on cell migration in primary cultured rat cortical astrocytes. We found that upon TCDD treatments at relative low concentrations (10− 10 and/or 10− 9 mol/L), the ability of primary astrocytes to migrate horizontally and vertically was promoted. In line with this cellular effect, the mRNA expression of two pro-migratory genes, including cell division cycle 42 (CDC42) and matrix metalloproteinase 2 (MMP2) was induced by TCDD treatment. Dioxin exerts its toxic effects mainly through aryl hydrocarbon receptor (AhR) pathway. So the role of AhR pathway in the pro-migratory effects of TCDD was examined using an AhR antagonist, CH223191. We found that application of CH223191 significantly reversed the pro-migratory effects of TCDD. Interestingly, the basal ability of horizontal migration as well as basal levels of CDC42 and MMP2 expression were dramatically reduced suggesting a possible physiological role of AhR in maintaining the endogenous migration ability of the primary astrocytes. These findings support the notion that dioxin promotes astrocyte reactivation at molecular and cellular levels.

Five isomorphic lanthanide metal-organic frameworks constructed from 5-(3-carboxy-phenyl)-pyridine-2-carboxylic acid (H2cppca) and oxalate (H2ox), {[Ln2(cppca)2(ox)(H2O)2]·2H2O}n [Ln = Eu (1), Gd (2), Nd (3), Pr (4),Tb (5)] have been successfully synthesized and characterized by single-crystal X ray diffraction, elemental analysis, IR spectroscopy, thermal analysis, and powder X-ray diffraction. In compounds 1–5, inorganic helical Ln-O chain and cppca2- anions are interconnected to form a one-dimension (1D) helical metal-organic chain, then 1D metal-organic chains are linked into a three-dimension achiral network with 1D channel of 6.31 × 10.13 A2, showing an unprecedented (4,5)-connected topology net with Schlafli symbol {44.62}{44.64.82}. Fluorescent experiment indicated that compounds 1 and 5 show sensitive luminescence quenching response to aniline, and the corresponding quenching constants (Ksv) are 2.81 × 104 M−1 and 3.14 × 104 M−1, respectively. The detection limits of aniline are 3.06 μM for 1 and 2.29 μM for 5. Moreover, compounds 1 and 5 are very stable and their reusability is relatively high and the fluorescence can be easily recovered after washing.

A novel Cu(I)-cluster based coordination compound formulated as {(Cu2I2)2[Cu6(dmpymt)6]}n (Hdmpymt = 4,6-dimethylpyrimidine-2-thione) was synthesized under solvo-thermal condition and characterized by single-crystal X ray diffraction, elemental analysis, IR spectroscopy, thermal analysis, and powder X-ray diffraction. Compound 1 is an infinite 3D structure composed of Cu2I2 and Cu6S6 binary Cu(I) clusters with 66 topology, and displays high thermal stability and good solvent stability. Fluorescence experiments illustrate that compound 1 displays apparently red luminescence emission and selectively turn-off fluorescence response for CrO42− and Cr2O72− in water, showing potential luminescent probes for detecting Cr(VI) ions.

Cancer occurrence and development are closely related to the environment. Aryl hydrocarbon receptor (AhR) is an important receptor mediating the toxic effects of many environmental compounds, and is also involved in regulating tumor cell migration. Glioblastoma is the most malignant glioma and exhibits high motility, but the effects of AhR on the migration of glioblastoma are still unclear. We aimed to understand the role of AhR in the migration of this type of tumor cell and to explore the underlying molecular mechanism. In cultured human neuroblastoma cells (U87), we found that AhR overexpression or knockdown increased or suppressed the migration ability of U87 cells, respectively. Furthermore, inhibition of basal activation of the AhR pathway suppressed migration ability, suggesting a positive correlation between endogenous activity of the AhR pathway and cell migration. When the AhR pathway was activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 6-formyl [3,2-b] carbazole (FICZ), the migration of U87 cells was inhibited by inducing the expression of a tumor suppressor, IL24, which is a downstream responsive gene of AhR activation. Moreover, a similar AhR-IL24-dependent mechanism for migration inhibition of TCDD was documented in a breast cancer cell line and a lung cancer cell line. This study demonstrated that AhR plays important roles in regulating the migration of glioblastoma, and the induction of the AhR-IL24 axis mediates the inhibition of migration in response to TCDD or FICZ treatment.

Inflammasomes, a critical component of the innate immune system, mediate much of the inflammatory response manifested by engineered nanomaterials. Iron oxide nanoparticles (IONPs), a type of nanoparticles that have gained widespread acceptance in preclinical and clinical settings, are known to induce inflammasome activation, but how morphology affects the inflammasome-activating property of IONPs has not been addressed. In this report, we have synthesized four morphologically distinct IONPs having the same aspect ratio and similar surface charge, thus offering an ideal system to assess the impact of morphology on nanoparticle-elicited biological effect. We show that morphology was a critical determinant for IONP-induced IL-1β release and pyroptosis, with the octapod and plate IONPs exhibiting significantly higher activity than the cube and sphere IONPs. The inflammasome-activating capacity of different IONPs correlated with their respective ability to elicit intracellular reactive oxygen species generation, lysosomal damage, and potassium efflux, three well-known mechanisms for nanoparticle-facilitated inflammasome activation. Furthermore, we demonstrate that the release of IL-1β induced by IONPs was only partly mediated by NLRP3, suggesting that inflammasomes other than NLRP3 are also involved in IONP-induced inflammasome activation. Our results may have implications for designing safer nanoparticles for in vivo applications.

With the increasing need of detecting chemical pollutants, modern analytical instruments show many advantages but also have some common drawbacks such as high operational cost and tedious pretreatment procedures. Thus, developing a fast, simple, and convenient colorimetric sensing system is a challenge. Here, a new Ag6S6 cluster-based coordination compound formulated as Ag6(dmpymt)6 (1) (Hdmpymt = 4,6-dimethylpyrimidine-2-thione) was synthesized under solvothermal condition and displayed apparently green luminescence emission and good stabilities in water and some organic solvents. Fluorescence experiments illustrated that 1 displayed efficiently naked eye colorimetric sensing for nitrobenzene (NB), Cr(VI), and Fe(III) ions by fluorescence quenching in the emulsions. The possible sensing mechanisms are attributed to the competitive absorption of excitation wavelength energy between the analytes and the compound 1. Furthermore, the fluorescent test papers of 1 were prepared as well and showed efficient, convenient, and easily recycled characteristics, presenting a potential sensing application for the environmental concerns.

Chemo-PTT, which combines chemotherapy with photothermal therapy, offers a viable approach for the complete tumor eradication but would likely fail in drug-resistant situations if conventional chemotherapeutic agents are used. Here we show that a type of copper (Cu)-palladium (Pd) alloy tetrapod nanoparticles (TNP-1) presents an ideal solution to the chemo-PTT challenges. TNP-1 exhibit superior near-infrared photothermal conversion efficiency, thanks to their special sharp-tip structure, and induce pro-survival autophagy in a shape- and composition-dependent manner. Inhibition of autophagy with 3-methyl adenine or chloroquine has a remarkable synergistic effect on TNP-1-mediated PTT in triple-negative (4T1), drug-resistant (MCF7/MDR) and patient-derived breast cancer models, achieving a level of efficacy unattainable with TNP-2, the identically-shaped CuPd nanoparticles that have a higher photothermal conversion efficiency but no autophagy-inducing activity. Our results provide a proof-of-concept for a chemo-PTT strategy, which utilizes autophagy inhibitors instead of traditional chemotherapeutic agents and is particularly useful for eradicating drug-resistant cancer., “Conventional chemotherapy-photothermal therapy combination has limited efficacy in drug resistant cancers. Here they develop Copper-palladium tetrapod nanoparticles to overcome these challenges and show them to work in synergy with autophagy inhibitors to treat drug resistant cancers”

A novel pillared-layer coordination polymer containing -Pb-O-Pb-Cu-Cl- inorganic sheets, [PbCuCl(3.5-pydc)]n (1) (3.5-H2pydc = pyridine-3,5-dicarboxylic acid), was obtained through the hydrothermal method. In compound 1, two symmetry-related Pb centers are bridged into a Pb2O2 dimer by two symmetrically carboxyl oxygen atoms from 3,5-pydc2− anions, each Pb2O2 dimer links four equivalent units into a 2D puckered Pb-O-Pb layer. Two symmetry-related Cu ions are bridged into a Cu2Cl2 dimer by two chlorine ions. Thus the -Pb-O-Pb- layer and Cu2Cl2 dimers are joined into a novel 2D puckered -Pb-O-Pb-Cu-Cl- inorganic layer. The 2D -Pb-O-Pb-Cu-Cl- inorganic layers are further pillared to form a 3D network through 3,5-pydc2− anions. To the best of our knowledge, the pillared-layer framework based on -Pb-O-Pb-Cu-Cl- inorganic layers has never been reported previously. Compound 1 exhibits weak blue light emission with the maximum at 383 nm upon excitation at 260 nm.

Dioxin can cause a series of neural toxicological effects. MicroRNAs (miRs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-miR-146b-5p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-miR-146b-5p. We found that the hsa-miR-146b-5p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-miR-146b-5p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-miR-146b-5p significantly suppressed acetylcholinesterase (AChE) activity and targeted the 3'-untranslated region of the AChE T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-miR-146b-5p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which AChE may serve as a responsive gene for mediating the effect.

Effectively constructing CuI/AgI-based coordination polymers containing Hmthd ligands is a challenging work, here, four new coordination compounds [Cu(Hmthd)2Cl]n (1), [Cu3(mthd)2Br]n (2), [Ag(mthd)]n (3) and [Ag2(mthd)I]n (4) have been obtained by reactions of the corresponding metal salts and 2-mercapto-5-methyl-1,3,4-thiadiazole (Hmthd) ligand under solvothermal conditions. All the compounds were fully characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum, thermalgravimetric analysis and powder X-ray diffraction. Compound 1 is a mononuclear coordination compound, in which two neutral Hmthd molecules and CuCl unit are coplanar. In compound 2, the anionic [CuBr(mthd)]22– units and one-dimensional coplanar cationic {[Cu2(mthd)]+}n chains are connected to each other to form a two-dimensional layered structure. In compound 3, two different one-dimensional puckered [Ag(mthd)]n chains are connected to each other to form a two-dimensional irregular layered structure, in which a (AgS)n chain constructed by staggered Ag3S3 rings is observed. Compound 4 is a two-dimensional double layer coordination framework containing a two-dimensional inorganic (Ag2IS)n double layer. Compound 4 shows the apparent yellow emission with the maximum at 551 nm while exciting at 333 nm, and displays sensitive luminescence quenching response to nitrobenzene with quenching constant (Ksv) of 5.07 × 103 M−1 and detection limit of 5.33 × 10−6 M. This research provides a new strategy to construct the CuI/AgI-based coordination compounds containing Hmthd ligands with extended structures through the synergistic effect of (mthd)- and halide ions.

A new purely inorganic 2D framework, {PMo12O40Bi2(H2O)2}·4H2O(1), was synthesized under solvothermal condition and characterized by infrared(IR) spectroscopy, thermal gravimetric analysis, UV-Vis spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction. Structural analysis reveals that compound 1 consists of Keggin unit {PMo12O40} with two bismuth atoms capping two opposite pits, leading to the bi-bismuth-capping Keggin polyoxometalate. Compound 1 not only displays excellent photodegradation activity for methyl orange(MO), but also has a high absorption capacity for rhodamine B(RhB) and methylene blue(MB). Moreover, compound 1 is extremely stable and easily separated from the reaction system for reuse.

Five new complexes based on 1-phenyl-1 H -tetrazole-5-thiol (Hptt): 1,1′-diphenyl-5,5′- dithiodi-tetrazole (abbreviated as dptt) ( 1 ), {[Co 2 (OH) 2 (2,2′-bipy) 2 (Hptt) 2 ]·(ptt) 2 ·(H 2 O) 2 }( 2 ), [Cd 2 I 2 (2,2′-bipy) 2 (ptt) 2 ] ( 3 ), [Co(ptt) 2 ] n ( 4 ) and [Cd(ptt) 2 ] n ( 5 ), have been synthesized and fully characterized by elemental analyses, thermogravimetric analysis, powder X-ray diffraction, IR spectra and single-crystal X-ray diffraction. Structural analysis indicated that compound 1 is an organic matter generated from in situ oxidative coupling reaction of Hptt ligands under the help of Fe 3+ ion. In compound 2 , two Hptt ligands adopting μ 2 - κ N, κ S bridging mode and two μ 2 -OH¯ bridge two Co(2,2′-bipy) fragments into a[Co 2 (OH) 2 (2,2′-bipy) 2 (Hptt) 2 ] 2+ core with short Co⋯Co distance (2.8185(10) A). In compound 3 , two Cd centers are joined into a dinuclear complex with short Cd⋯Cd distance (3.9282(14) A) by two ptt¯ anions in μ 2 - κ S, κ S bridging mode. Compounds 4 and 5 are isostructural and both feature one-dimensional (1D) looped chain structures containing 8-membered [M 2 S 2 C 2 N 2 ] rings (M = Co for 4 , M = Cd for 5 ). Variable-temperature magnetic susceptibility measurement of compounds 2 and 4 reveal strong antiferromagnetic interactions between Co centers. The fluorescent properties of compounds 1 , 3 and 5 are investigated in the solid state.

Two zinc supramolecular isomers, formulated as α-[Zn(cis-cppca)(H2O)]n (1) and β-[Zn(trans-cppca)(H2O)]n (2), have been synthesized under solvothermal conditions and fully characterized (H2cppca = 5-(3-carboxy-phenyl)-pyridine-2-carboxylic acid). Solvent-induced conformational isomerism of cppca2− ligand and framework isomerism of 1 and 2 are both observed. Each distorted [Zn(cis-cppca)]2 unit joined four equivalent ones in an abnormal 2D puckered layer in compound 1; however, compound 2 displays a 3-D open framework with larger bi-edge channels constructed by 1D Zn–O–Zn chains and trans-cppca bridges, in which the internal edge is a nearly hexagonal channel with an approximate dimension of 14.51 A and the external edge is a circular channel with an approximate dimension of 19.26 A. Fluorescent properties indicated that compound 1 displays an apparent fluorescence emission in acetone solvent; however, compound 2 was very sensitive to acetone molecules which results in nearly 100% fluorescence quenching. Moreover, compounds 1 and 2 might be promising luminescent probes for the detection of Fe3+. The dye adsorption experiments demonstrated that compound 2 showed good adsorption properties for MB and RhB molecules.

Six new coordination compounds Ni(cppca)(H2O)4·2H2O (1), Co(cppca)(H2O)4·2H2O (2), {Cd2(cppca)2(H2O)5}n (3), {[Cd3(cppca)2(H2P2O7)(H2O)6]·2H2O}n (4), {Cu(Hcppca)2}n (5) and {[Mn7(cppca)6(Hcppca)2(H2O)10]·2H2O}n (6) have been obtained by reactions of the corresponding metal salts and the rigid ligand 5-(3-carboxy-phenyl)-pyridine-2-carboxylic acid (H2cppca) under solvothermal conditions. All the compounds were fully characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, thermal analysis and powder X-ray diffraction. The single-crystal X-ray analyses showed that compounds 1–6 have rich structural chemistry ranging from mononuclear (1 and 2), one-dimensional (3 and 4), two-dimensional (5) to three-dimensional (6) structures. Moreover, the framework of compound 6 may be simplified into a 3-nodal net with Schlafli symbol {42·6}{42·82·102}{43·62·8·104}2, which shows an unprecedented (3,4,5)-connected topology net. The fluorescent properties of compounds 3 and 4 were investigated in the solid state and in various solvent emulsions, which indicated that compounds 3 and 4 are both highly sensitive fluorescent probes for the acetone molecules. Variable-temperature magnetic susceptibility measurements indicate weak antiferromagnetic interactions between metal centers in compounds 1, 2, 5 and 6.

Dioxin exposure is reported to affect nervous system development and increase the risk of neurodegenerative diseases. Generally, dioxin exerts its neurotoxicity via aryl hydrocarbon receptor (AhR). Neurofilament (NF) light (NFL) protein is a biomarker for both neuronal differentiation and neurodegeneration and its expression is controlled by the mitogen-activated protein kinase (MAPK) pathway. However, the effects of dioxin on NFL expression and involved mechanisms are incompletely understood. We aimed to investigate the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on NFL expression and elucidate the underlining signaling pathways and their potential crosstalk, specifically between MAPK and AhR pathway. We employed primary cultured rat cortical neurons to evaluate the effect of TCDD exposure on NFL expression. We also used nerve growth factor (NGF)-treated PC12 cells with specific inhibitors to investigate the involvement of and potential crosstalk between the MAPK pathway and the AhR pathway in mediating the effects of TCDD on NFL expression. After TCDD exposure, NFL mRNA and protein levels were upregulated in cultured neurons. NFL protein was preferentially found in the cell body compared with neurites of the cultured neurons. In PC12 cells, TCDD enhanced both NGF-induced NFL expression and phosphorylation of ERK1/2 and p38. The addition of MAPK-pathway inhibitors (PD98059 and SB230580) partially blocked the TCDD-induced NFL upregulation. CH223191, an AhR antagonist, reversed the upregulation of NFL and phosphorylation of ERK1/2 and p38 induced by TCDD. This study demonstrated TCDD-induced upregulation of NFL in cultured neurons, with protein retained in the cell body. TCDD action was dependent on activation of AhR and MAPK, while crosstalk was found between these two signaling pathways.

Acetylcholinesterase (EC3.1.1.7; AChE) is a key enzyme in the cholinergic system. Emerging evidence has shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a typical persistent organic pollutant, suppressed neuronal AChE activity via dysregulation of different biosynthesis processes in human and rat neuronal cells. In the nervous system, astrocytes protect neurons from environmental pollutants. As a known target cell of TCDD, the astrocyte might be involved in TCDD effects on neuronal AChE. Therefore, in the present study, we found astrocyte-derived conditioned medium (ACM) could induce AChE activity preferentially in mature neurons in the absence of TCDD. The enzymatic activity of AChE was generally decreased in cultured cortical neurons upon direct treatment with TCDD (0.003–0.01 nM). This trend of changes in AChE activity was not significantly altered in immature neurons exposed to ACM produced in the presence of TCDD (TACM group), but reversed in mature neurons. Compared with effects of treatment with ACM plus TCDD (ACMT), a significant differential effect on AChE activity was found in the TACM group in response to TCDD treatment specifically in immature neurons, suggesting the presence of a TCDD-specific active component derived from the astrocyte. Inconsistent alterations in expression and enzymatic activities of the AChE T subunit (AChET) and the proline-rich membrane anchor (PRiMA) were found, suggesting that a mechanism of action beyond the transcriptional level might be involved. These data indicate that the astrocyte might play a protective role in TCDD-induced alterations of neuronal AChE in certain stages of differentiation.

S-allyl-cysteine sulfoxide (alliin) is the main organosulfur component of garlic and its preparations. The present study aimed to examine the protective effect of alliin on cardiac function and the underlying mechanism in a mouse model of myocardial infarction (MI). Notably, alliin treatment preserved heart function, attenuated the area of infarction in the myocardium of mice and reduced lesions in the myocardium, including cardiomyocyte fibrosis and death. Further mechanistic experiments revealed that alliin inhibited necroptosis but promoted autophagy in vitro and in vivo. Cell viability assays showed that alliin dose-dependently reduced the necroptotic index and inhibited the expression of necroptosis-related receptor-interacting protein 1, receptor-interacting protein 3 and tumor necrosis factor receptor-associated factor 2, whereas the levels of Beclin 1 and microtubule-associated protein 1 light chain 3, which are associated with autophagy, exhibited an opposite trend upon treatment with alliin. In addition, the level of peroxisome proliferator-activated receptor γ was increased by alliin. Collectively, these findings demonstrate that alliin has the potential to protect cardiomyocytes from necroptosis following MI and that this protective effect occurs via the enhancement of autophagy.

Sustaining blood retention for theranostic nanoparticles is a big challenge. Various approaches have been attempted and have demonstrated some success but limitations remain. We hypothesized that peptides capable of increasing blood residence time for M13 bacteriophage, a rod-shaped nanoparticle self-assembled from proteins and nucleic acids, should also prolong blood circulation for engineered nanoparticles. Here we demonstrate the feasibility of this approach by identifying a series of blood circulation-prolonging (BCP) peptides through in vivo screening of an M13 peptide phage display library. Intriguingly, the majority of the identified BCP peptides contained an arginine-glycine-aspartic acid (RGD) motif, which was necessary but insufficient for the circulation-prolonging activity. We further demonstrated that the RGD-mediated specific binding to platelets was primarily responsible for the enhanced blood retention of BCP1. The utility of the BCP1 peptide was demonstrated by fusion of the peptide to human heavy-chain ferritin (HFn), leading to significantly improved pharmacokinetic profile, enhanced tumor cell uptake and optimum anticancer efficacy for doxorubicin encapsulated in the HFn nanocage. Our results provided a proof-of-concept for an innovative yet simple strategy, which utilizes phage display to discover novel peptides with the capability of substantially prolonging blood circulation for engineered theranostic nanoparticles.

A novel [Dy4(OH)4]-based porous coordination polymer with double-wall structure, [Dy(OH)(cppc)]n (1) (H2cppc = 5-(4-carboxyphenyl)pyridine-2-carboxylic acid), has been successfully obtained through solvo-thermal method and characterized by elemental analysis, IR spectrum, powder X-ray diffraction, single-crystal X-ray diffraction and thermal analysis. Structure analysis shows compound 1 is a three-dimensional porous coordination polymer with double-wall structure constructed by [Dy4(OH)4]8+ cubane-like units and (cppc)2− anions, in which one-dimensional square channels with the dimensions 11.78 × 11.78 A2 are observed. Topology analysis reveals compound 1 has an unprecedented (3, 12)-connected topology net with Schlafli symbol {420.628.818}{43}4. Thermal analysis indicates the framework of compound 1 kept thermally stable until 370 °C. Fluorescent experiment indicates that compound 1 show apparently blue light emission in the solid state. Variable-temperature magnetic susceptibility measurement indicates strong antiferromagnetic interactions in [Dy4(OH)4]8+ SBU for compound 1.

Emerging evidence suggests that perinatal dioxin exposure affects neurodevelopment and impairs multiple brain functions, including cognitive, language, learning and emotion, in the offspring. However, the impacts of gestational and lactational exposure to dioxin on behavior and related molecular events are still not fully understood. In this study, female C57BL/6J mice were orally administered three doses of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) (0.1 or 10 μg/kg body weight (bw)) during the pregnancy and lactation periods. The locomotion, exploration and anxiety-related behaviors were examined by an open field test of the young adult female offspring at postnatal day 68. We found that the maternal TCDD exposure, particularly at a low dose, increased movement ability, novelty-exploration and certain anxiety-related behaviors in the offspring. Such hyperactivity-like behaviors were accompanied by the upregulation of certain genes associated with cholinergic neurotransmission or synaptogenesis in the offspring brain. In accordance with the potential enhancement of cholinergic neurotransmission due to the gene upregulations, the enzymatic activity of acetylcholinesterase was decreased, which might lead to excess acetylcholine and consequent hyper-excitation at the synapses. Thus, we found that gestational and lactational TCDD exposure at low dose caused hyperactivity-like behaviors in young adult female offspring and speculated the enhancement of cholinergic neurotransmission and synaptogenesis as potential molecular events underlying the neurobehavioral effects.

Three new imidazole-based dicarboxylate metal compounds, {Ni(HMIDC)(bpp)}n (1), {[Ni4(HEIDC)4(H2O)8]·H2O}n (2), and {Co3(EIDC)2(py)2(H2O)2}n (3) have been synthesized and characterized by elemental...

Two new coordination compounds, { Pb(pymt) 2 } ∞ ( 1 ) and { Pb(mpymt) 2 } ∞ ( 2 ) (pymt = pyrimidine-2-thiolate and mpymt = 4-methyl-pyrimidine-2-thione) have been synthesized under solvothermal conditions and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. In compounds 1 and 2 , pymt − and mpymt − adopt the same coordination modes ( μ −1 κ N, S and μ 2 −1 κ N, S: 2 κ S, N) to interacted with Pb 2+ , however, different topology structures for compounds 1 and 2 are obtained. Compound 1 displays a one-dimensional (1D) ribbon with square cavity constructed from two double concentric chains of [Pb-S] ∞ and [Pb-Pyrimidine] ∞ sharing Pb1 ions. Compound 2 shows 1D polymeric single chain constructed by [Pb-S] ∞ and [Pb-methyl-pyrimidine] ∞ chains. The results revealed that the methyl groups don't influence the coordination modes of pyrimidine-2-thiolate but directed the structural variations. Moreover, the fluorescent properties of compounds 1 and 2 were investigated.

A novel coordination polymer with the chemical formula [Cu4Br(CN)(mtz)2]n (mtz = 5-methyl tetrazole) (), has been synthesized under solvothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Interestingly, the Cu(i), CN(-) and mtz(-) in compound are all generated from an in situ translation of the original precursors: Cu(2+), acetonitrile and 1-methyl-5-mercapto-1,2,3,4-tetrazole (Hmnt). The in situ ring-to-ring conversion of Hmnt into mtz(-) was found for the first time. Structural analysis reveals that compound is a novel 3D tetrazole-based Cu(i) coordination polymer, containing both metal halide cluster Cu6Br2 and metal pseudohalide cluster Cu2(CN)2 secondary building units (SBUs), which shows an unprecedented (3,6,10)-connected topology. Notably, a pseudo-porphyrin structure with 16-membered rings constructed by four mtz(-) anions and four copper(i) ions was observed in compound . The fluorescence properties of compound were investigated in the solid state and in various solvent emulsions, the results show that compound is a highly sensitive naked-eye colorimetric sensor for NB and 2-NT (NB = nitrobenzene and 2-NT = 2-nitrotoluene).

Three novel Cu6S6 cluster-based coordination compounds formulated as [Cu(mpymt)3]2 (1), {(CuBr4)[Cu(mpymt)6]}n (2), and {(CuI6)[Cu(mpymt)6]}n (3) (Hmpymt = 4-methylpyrimidine-2-thione), have been synthesized under solvothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Structural analysis reveals that compound 1 shows a distorted octahedral core of six copper atoms (Cu6S6) constructed from four α and two β type N[double bond, length as m-dash]C-SH parts from six mpymt(-) anions. Compound 2 displays an interesting 3D framework constructed from Cu6S6 and Cu4Br4 Cu(i) clusters simultaneously, interestingly, six mpymt(-) with α type N[double bond, length as m-dash]C-SH parts are involved in the formation of Cu6S6. Compound 3 displays an infinite 1D framework constructed from Cu6S6 and Cu6I6 Cu(i) clusters, notably, four α and two β type N[double bond, length as m-dash]C-SH parts are involved in the formation of the Cu6S6 cluster, however, only mpymt(-) ligands containing α type N[double bond, length as m-dash]C-SH parts form the bridged Cu6I6 cluster. The experimental results reveal that halogen ions finely modulate the structural features of compounds 1-3. The fluorescent properties of compounds 1-3 in the solid state and in various solvent emulsions were investigated in detail, the results of which indicate that compounds 1-3 are all highly sensitive naked eye colorimetric sensors for NB, 2-NT and Fe(3+) (NB = nitrobenzene and 2-NT = 2-nitrotoluene).

Eight new coordination polymers (CPs) were successfully synthesized through the solvo-thermal reactions of H2cppc ligand and a series of transition metal salts, [M(cppc)(H2O)2]n [M = Co, (1); Ni, (2); Zn, (3); Cd, (4)], [M(Hcppc)2]n [M = Cd, (5); Mn, (6); Cu, (7)], [Pb(cppc)(H2O)]n (8), [H2cppc = 4-(4-carboxy-phenyl)-pyridine-2-carboxylic acid]. These compounds were all characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction and thermal analysis. Compounds 1–4 have similar molecular formula except for different metal centers, notably, compounds 1–3 with isomorphic frameworks display two-dimensional layer structure, in which contain left- and right-handed chiral chains constructed from M2(H2O)2 dimers and cppc2− anions. However, compound 4 exhibits a three-dimensional network with Cd-O-Cd inorganic chains, different from that of compounds 1–3. Compounds 5–7 also have similar molecular formula except for different metal centers, the isomorphic compounds 5 and 6 exhibit two-dimensional undulating layers, while compound 7 displays one-dimensional chain. Compound 8 is a 2D layer structure with Pb2O2 secondary building units. In general, coordination geometries of metal centers and coordination modes of the ligands have an important effect on the structures of targeted compounds. Fluorescent experiments indicate that compounds 3–5 and 8 display apparently blue light emission in the solid state. Magnetic properties of compounds 1, 2, 6 and 7 are also investigated.

Aryl hydrocarbon receptor (AhR) plays important roles in the interferences of dioxin exposure with the occurrence and development of tumors. Neuroblastoma is a kind of malignant tumor with high mortality and its occurrence is getting higher in dioxin exposed populations. However, there is still a lack of direct evidence of influences of dioxin on neuroblastoma cell migration. SK-N-SH is a human neuroblastoma cell line which has been used to reveal 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced dysregulation of certain promigratory gene. Thus, in this study, we employed SK-N-SH cells to investigate the effects of TCDD on the spontaneous movement of neuroblastoma cells, which is a short-range cell migratory behavior related to clone formation and tumor metastasis in vitro. Using unlabeled live cell imaging and high content analysis, we characterized the spontaneous movement under a full-nutrient condition in SK-N-SH cells. We found that the spontaneous movement of SK-N-SH cells was inhibited after 36- or 48-h treatment with TCDD at relative low concentrations (10−10 or 2 × 10−10 M). The TCDD-treated cells were unable to move as freely as that of control cells, resulting in less diffusive trajectories and a decreased displacement of the movement. In line with this cellular effect, the expression of pro-adhesive genes was significantly induced in time- and concentration-dependent manners after TCDD treatment. In addition, with the presence of AhR antagonist, CH223191, the effects of TCDD on the gene expression and the spontaneous cell movement were effectively reversed. Thus, we proposed that AhR-mediated up-regulation of pro-adhesive genes might be involved in the inhibitory effects of dioxin on the spontaneous movement of neuroblastoma cells. To our knowledge, this is the first piece of direct evidence about the influence of dioxin on neuroblastoma cell motility.

Two new complexes with homochiral frameworks, {Co3(EIDC)2(H2O)5}n (1) and {Zn3(EIDC)2(H2O)4}n (2) (H3EIDC = 2-ethyl-1H-imidazole-4,5-dicarboxylic acid), have been synthesized from achiral starting precursors via spontaneous resolution and fully characterized by elemental analyses, IR, circular dichroism, photoluminescence (PL) spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis. X-ray diffraction data revealed that 1 and 2 have SrSi2 topologies and that both are homochiral metal–organic frameworks. Compound 1 is constructed by left-handed chiral chains; however, right-handed chains constitute the homochiral framework of 2. Variable temperature magnetic susceptibility measurements of 1 indicate strong antiferromagnetic interactions between the magnetic Co centers. Compound 2 exhibited weak blue PL in the solid state at room temperature.

Ligustrum purpurascens, named as "Ku ding cha", has been used as a kind of functional tea in southern China for about two thousand years, which has the effects on diuresis, anti-hypertension, weight-loss and anti-inflammation.This study was aimed to investigate the immune enhancement effects of the crude phenylethanoid glycosides (CPGs) from Ligustrum. Purpurascens on mice and analyze the chemical profiles of phenylethanoid glycosides in the CPGs.The immune functions enhancing potential of CPGs was determined using serum hemolysin antibody, phagocytosis, splenocyte antibody production, and NK cells activity assays. The contents of five major constituents in the crude glycosides of Ligustrum purpurascens were determined by using liquid chromatography, other five glycosides were deduced according to their UV and MS spectra compared with the literature as well.In the immunizing experiment, mice treated with different doses of CPGs showed an increase (p0.01) in the haemagglutination titre compared with the control group. The increases (p0.05) were found to be significant at doses of 440 mg/kg and 1.32 g/kg in the experiments of antibody production of spleen cells, MΦ phagocytosis of chicken RBCs and NK cell activity. Further chemical characterization yielded 10 constituents from CPGs, five glycosides were quantified by HPLC and the structures of other five compounds were speculated according to their UV and MS spectra.The results suggested that phenylethanoid glycosides from Ligustrum purpurascens have immunomodulatory effects on mice.

Tetrahydropalmatine exerts numerous pharmacological activities, including analgesic and narcotic effects; anti-arrhythmic, blood pressure lowering and cardioprotective effects; protective effects against cerebral ischemia-reperfusion injury; inhibition of platelet aggregation; prevention of ulcerative diseases and inhibition of gastric acid secretion; antitumor effects; and beneficial effects on the withdrawal symptoms associated with drug addiction. The present study aimed to investigate the protective effects of tetrahydropalmatine against ketamine‑induced learning and memory impairment in mice. The Morris water maze test and open field test were used to analyzed learning and memory impairment in mice. ELISA kits and western blotting were used to analyze oxidative stress, inflammation factors, caspease‑3 and caspase‑9, iNOS, glial fibrillary acidic protein (GFAP), glial cell‑derived neurotrophic factor (GDNF), cytochrome c and phospholipase C (PLC)‑γ1 protein expression. The results demonstrated that tetrahydropalmatine treatment significantly decreased escape latency in the learning phase and increased the number of platform site crossings in ketamine‑induced mice. In addition, tetrahydropalmatine significantly inhibited oxidative stress, inflammation and acetylcholinesterase activity, and decreased acetylcholine levels in ketamine‑induced mice. Tetrahydropalmatine also suppressed iNOS protein expression, weakened caspase‑3 and caspase‑9 activation, inhibited nuclear factor‑κB, glial fibrillary acidic protein, cytochrome c and phospholipase C‑γ1 protein expression, and induced glial cell‑derived neurotrophic factor protein expression in ketamine‑induced mice. Taken together, these results indicated that tetrahydropalmatine may protect against ketamine‑induced learning and memory impairment in mice via antioxidative, anti‑inflammatory and anti‑apoptotic mechanisms. The present study provided an experimental basis for the clinical application of tetrahydropalmatine to reduce the severe side effects associated with ketamine therapy in future studies.

Three complexes based on methyl-pyrimidine-2-thione, 5-methyl-5,8,9,10-tetrahydro-5,9methanopyrimido[5,4-e][1, 3]diazocine-2,7-dithiol (mtmdd) (1), and Ni(mpymt)2(N2H4)·H2O (2) and [Cd(mpymt)2]∞ (3) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. Structural analysis reveals that 1 is generated from an in situ translation of mpymt. In 2, two Ni(mpymt)2 fragments were joined into a dinuclear complex by two NH2–NH2 molecules. Compound 3 is a two-dimensional Cd coordination polymer constructed by Cd2(mpymt)2 SBUs and mpymt anions. Variable-temperature magnetic susceptibility measurement of 2 revealed strong antiferromagnetic interactions between nickel magnetic centers. The fluorescent properties of 1 and 3 were investigated in the solid state.

Four new fpa-metal complexes, [Co(fpa)2(H2O)2] (1), [Cu(fpa)2(H2O)] (2), [Zn2(fpa)4(bpp)2] n (3), and {[Zn(bpy)(H2O)4] · 2(fpa)} n (4), have been synthesized and fully characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA), (Hfpa = 2,2-difluoro-2-(pyridine-2-yl)acetate, bpp = 1,3-bis(4-pyridyl)propane, bpy = 4,4′-bipyridine). X-ray diffraction analyses reveal that 1 and 2 with 0-D structures are both extended into 3-D supramolecular networks through hydrogen bonds and π···π interactions. Complex 3 with chiral centers possesses a 1-D structure constructed by two kinds of bpp molecules and four kinds of fpa− molecules with different conformations, with bbp and fpa− bridging and capped ligands, respectively. In 4, bpy links [Zn(H2O)4]2+ into a 1-D polymeric cationic chain and uncoordinated fpa− compensates the framework charge. The results of TGA reveal that fpa− decomposes through two processes. Both 3 and 4 show strong fluorescence in th...

Two cobalt complexes, [Co3(L)2(CH3OH)2(μ3-OH)2] (1) and [Co(L)(bpe)0.5]·H2O (2) [H2L = 5-(4-carboxyphenoxy)-pyridine-2-carboxylic acid; bpe = 1, 2-bis(4-pyridyl)ethylene] were synthesized and fully characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analysis (TGA), and magnetic analysis. Complex 1 has a two-dimensional (2D) structure with puckered Co–O–Co chains, and 2 displays a three-dimensional (3D) network containing one-dimensional rectangular channels with dimensions of 9.24 × 13.84 A. In complex 1, variable-temperature magnetic susceptibility measurements indicate antiferromagnetic interactions between cobalt magnetic centers.

Three new cpt-metal complexes of different topology structures were synthesized by solvothermal methods [Hcpt = 4-(4-carboxyphenyl)-1,2,4-triazole]. The structure of [Mn(cpt)2·2H2O] (1) is essentially 0D monomeric, but extended into a 2D supramolecular network through cross-linking hydrogen bonds. In [Cu(cpt)(OH)·2H2O]·2H2O (2), the hydroxo groups as well as cpt ligands join the copper ions into an infinite polymeric [Cu(μ-cpt)(μ-OH)] chain, which is interconnected into a 3D supramolecular network with different oriented channels by 1D water chains. The complex [Zn(cpt)2]·0.5DMF·CH3CH2OH (3), which crystallizes in a 3D open framework with fourfold interpenetrated diamondoid network topology, represents the first 3D structure based on cpt anions. The structure differences demonstrate that the reaction metal ions have an important effect on the structures of these complexes.

Reaction of 2-methyl-imidazole-4,5-dicarboxylic acid (H3MIDC) with different salts (Zn and Mn) has led to three new H n MIDC–metal complexes varying from zero- to two-dimensional structures under hydrothermal and solvothermal conditions. The complex [Zn(H2MIDC)2(H2O)2] (1) is a 0-D complex constructed by H2MIDC− and Zn centers and the complex [Mn(HMIDC)(H2O)2] · H2O (2) is a polymeric 1-D chiral chain constructed by HMIDC2− and Mn centers connected into a 3-D supramolecular framework with a 1-D channel. The complex [Zn3(MIDC)2(H2O)2(DMF)2] · 0.5H2O (3) shows a 2-D puckered structure composed of MIDC3− and Zn. The differences of the three complexes demonstrate that reaction solvent and temperature have important effects on the structure of these complexes. Complex 3 shows strong fluorescence in the solid state at room temperature.

A series of lanthanide coordination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4), H{sub 2}ip=isophthalic acid, im=imidazole] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been synthesized and characterized by elemental analyses, infrared (IR), ultraviolet-visible-near infrared (UV-Vis-NIR) and single-crystal X-ray diffraction analyses. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 features a 2-D network making of two different kinds of quadruple-helical chains. Compounds 2 and 3 present the characteristic emissions of Pr(III) and Nd(III) ions in NIR region, respectively. Compound 4 shows sensitized luminescence of Dy(III) ions in visible region. - Graphical abstract: A series of lanthanide coodination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4)] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been reported. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 displays a 2-D network making of two kinds of quadruple-helical chains. Display Omitted.

A series of lanthanide(III) complexes with citric ligand, [Ln(Hcit)(H2O)]n (Ln = Ce (1), Pr (2), Sm (3), Dy (4) and Er (5)), have been synthesized and characterized by elemental analysis, IR, TGA and single-crystal X-ray diffraction. X-ray structural analysis reveals that complexes 1 and 2 are isomorphous and feature 3D networks showing five-connected distorted BN topology, while the isostructural 3–5 display 2D layer structures with two kinds of 13-membered rings. Variable-temperature magnetic susceptibility measurements for complexes 1 and 5 indicate there exist antiferromagnetic interactions between magnetic centers.

Four 3D lanthanide(III) complexes with 5-sulfosalicylic acid (H3SSA) as bridging ligands, Ln(SSA)(H2O)2 [Ln=Ce(III) (1), Pr(III) (2), Nd(III) (3) and Dy(III) (4)], have been synthesized and characterized by elemental analysis, IR, XRD and single-crystal X-ray diffraction. X-ray structural analysis reveals that isostructral complexes 1–4 possess 3D structures with 4664 topology. Complexes 1 and 2 exhibit broad intraligand fluorescent emission bands. Complexes 3 and 4 not only display intraligand fluorescent emission bands, but also present Nd(III) characteristic emission in the near-IR region and sensitized luminescence of Dy(III) ions in the visible region, respectively. Variable-temperature magnetic susceptibility measurements of 2–4 have been studied over the temperature range of 4–300 K.

Two new coordination complexes, [Ni 2 (Him) 12 · (bta) · 8H 2 O] 1 and [Cd 2 (Him) 4 (bta)] 2 , (H 4 bta = 1,2,4,5-benzenetetracarboxylic acid, Him = imidazole) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. X-ray diffraction reveals that complex 1 , consisting of two crystallographically independent [Ni(Him) 6 ] 2+ fragments, an uncoordinated bta 4− anion and eight lattice water molecules, displays an interesting 3D supramolecular network constructed by cationic layers (layer A) and anionic layers (layer B) with ABAB sequence through hydrogen bonding interactions. In complex 2 , each bta ligand links four metal ions to form a one dimensional (1D) double chain. The 1D double metal chains are assembled into a 3D supramolecular network through N H⋯O hydrogen bonding and C H⋯π interactions. Complex 2 shows strong blue fluorescence at room temperature.

Two novel coordination polymers, {[Cu(ip)(Him)2(DMF)]·H2O} (1) and Co(ip)(Him)2 (2), (ip = isophthalate, Him = imidazole) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. X-ray structural analysis reveals that 1-D zigzag metal-organic chains are connected to form a 3-D supramolecular framework in compounds 1 and 2 by hydrogen-bonding and π–π interaction or other intermolecular contacts. Infrared, UV–vis, and elemental analysis were performed to characterize the two compounds. The result of magnetic determination for compound 2 shows there exist antiferromagnetic interaction between magnetic centers.

Six new complexes constructed by 5-sulfosalicylic acid and bipyridyl-like ligands (2,2′-bipy and 1,10-phen), namely [Cu4(OH)2(ssal)2(phen)4 · 7H2O] (1), [Cu4(OH)2(ssal)2(bipy)4 · 2H2O] (2), [Cd(Hssal)(bipy)] (3), [Cd(HL)2(phen)2] (4), [Cr(ssal)(bipy)(H2O)2 · 2H2O] (5) and [Cr(ssal)(phen)2] (6) (H3ssal = 5-sulfosalicylic acid, H2L = p-hydroxybenzenesulfonic acid, bipy = 2,2′-bipy, phen = 1,10-phen) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. Complexes 1 and 2 are both tetranuclear copper complexes with a stepped topology. In complex 3, a new coordination mode of the Hssal2− group is reported in this work. During the synthetic process of complex 4, in situ decarboxylation of 5-sulfosalicylic acid into p-hydroxybenzenesulfonic acid is involved. Two chromium 5-sulfosalicylates (5 and 6) are reported for the first time. These new complexes display different supramolecular structures by O–H⋯O, C–H⋯O hydrogen bonds as well as π⋯π, C–H⋯π and O⋯π interactions. The results of magnetic determination show that ferromagnetic interactions exist in complex 1, however, antiferromagnetic interactions exist in 2.

Five metal imidazole dicarboxylate-based compounds, {[Zn3(MIDC)2(4,4′-bipy)3](4,4′-bipy)·8H2O}n (1), {[Co3(MIDC)2(4,4′-bipy)3](4,4′-bipy)·6H2O}n (2), {[Co3(MIDC)2(py)2(H2O)2]}n (3), {[Mn6(MIDC)4(py)5(H2O)4]}n (4), and {[Mn3(MIDC)2(Phen)3(H2O)2]}n (5) (H3MIDC = 2-methyl-1H-imidazole-4,5-dicarboxylic acid; 4,4′-bipy = 4,4′-bipyridine; py = pyridine; Phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. We control the coordination modes of H3MIDC via hydrazine and obtained a series of coordination compounds containing honeycomb-like [M3(MIDC)2]n layers. We also investigated the effects of different neutral terminal or bridging ligands on [M3(MIDC)2]n layers. Coplanar [M3(MIDC)2]n layers and 4,4-bipy were used to construct 3-D frameworks of 1 and 2. Puckered [M3(MIDC)2]n layers were found in 3–5; 4 is the first [M3(L)2]n layer structure with two crests and troughs during each period (L = imidazole-4,5-dicarboxylic acid or its analog). Compound 5 is the first puckered [M3(L)2]n layer structure decorated by chelating neutral ligands. Compound 1 exhibits weak blue photoluminescence in the solid state at room temperature. Variable-temperature magnetic susceptibility measurements of 2–5 indicate strong antiferromagnetic interactions.

A novel coordination polymer, {[Cu(ip)(Him)2(H2O)] · 3H2O} (1), (ip = isophthalate, Him = imidazole) was prepared under hydrothermal conditions and its structure is determined by single-crystal X-ray diffraction. X-ray structural analysis reveals that 1D zigzag metal-organic framework was connected to form a 3D metal-organic framework by a novel infinite 1D water chain constructed by five- and six-membered rings through edge-sharing. These water chains behave as glue to stabilize the 3D network. Upon removal of the water molecules by heating, the 3D structure breaks down. Thermogravimetric analysis, infrared, X-ray powder diffraction studies, elemental analysis and magnetic analysis were performed to characterize this compound.

[Ag(NH3)2]+ ions are chosen as an initial reaction precursor because of its simple displacement reaction and intrinsic arrangement as well as specific coordination directionality. Two new silver(I) ammine complexes, Ag2(NH3)HL2 (2) and Ag2(NH3)2HL3 (3), were obtained by a simple substitution reaction between [Ag(NH3)2]+ ions and pyridine-4,5-imidazoledicarboxylic acid [H3L2 = 2-(3′-pyridyl) 4,5-imidazoledicarboxylic acid and H3L3 = 2-(4′-pyridyl) 4,5-imidazoledicarboxylic acid]. Silver dimers are connected into a 2D layer and 1D chain in complexes 2 and 3, respectively. In complex 2 two kinds of displacement reactions (mono-substituting and bis-substituting) occurred between the ammine molecules in [Ag(NH3)2]+ ions and H3L2, however, only the mono-substituting reaction occurs in complex 3.

In the crystal structure of the title compound, C17H10N4O5, the molecules lie on twofold axes (through the ketone bridge C and O atoms). The dihedral angle between the two phthalazine rings is 52.25 (1)°. In the crystal, intermolecular N—H...O and O—H...O interactions link the molecules.