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Metal-organic cages, a class of supramolecular containers constructed by the self-assembly of metal ions and organic ligands, show great promise as catalytic agents. In this work, we designed and synthesized a series of rhombic dodecahedral Ni-Cu heterometal imidazolate cages (Ni8Cu6L24) that can act as highly active photo-Fenton-like catalysts. These cages possess a high ability to generate hydroxyl radicals (•OH) under visible light in the presence of H2O2, which can rapidly degrade organic pollutants (e.g., rhodamine B, methylene blue, and methyl orange) into CO2 and H2O. Besides, they are robust catalysts, with high catalytic activity and reusability under conditions in high H2O2 concentration, providing potentially advanced materials for degrading persistent organic pollutants.

A unique metal-organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unh topology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

As a creation platform for multifunctional materials, crystalline metal–organic frameworks (MOFs) can integrate different chromophores through reticular chemistry to adjust their spatial arrangement and intermolecular interaction, in turn achieving the purpose of improving the nature of optoelectronic properties. Herein, a stepwise reticular synthesis approach is successfully used to construct a multicomponent MOF, in which the well-known bis-terpyridyl ruthenium chromophore is orderly arranged into the skeleton of the material. Remarkably, this method promotes the excited state lifetime of the bis-terpyridyl ruthenium core, by two orders of magnitude (from 0.39 to 22.09 ns), to the extent that it can produce singlet oxygen under visible light irradiation at room temperature. Meanwhile, the obtained multicomponent MOF has been established to have considerable porosity for exposure of substrates to the catalytic sites, rendering it suitable for heterogeneous photocatalysis, including as a photooxidation detoxifier for sulfur mustard simulant. Moreover, DFT and TDDFT calculations reveal that the synergistic charge transfer among different components in the MOF may play a crucial role in improving the excited state properties of the bis-terpyridyl ruthenium motif.

Polynuclear silver clusters are described that unexpectedly transform from cyclic trinuclear complexes (CTCs) upon reacting with σ-donating phenylacetylene, featuring a noria-like conformation. The introduction of foreign copper ions leads to isomorphic bimetallic Ag/Cu clusters, with a boost in the photoluminescence quantum yield relative to the original silver clusters.

The exploration of highly efficient materials for the degradation of chemical warfare agents has been a longstanding task for preventing human exposure. Herein, we report a series of metal-organic frameworks (MOFs) M-TCPP-La based on metallo-tetra(4-carboxyphenyl)porphyrin and LaIII, which were applied to selectively oxidize 2-chloroethyl ethyl sulfide (CEES, a sulfur mustard simulant) as heterogeneous photocatalysts. After irradiation from a commercial blue light-emitting diode (LED), both superoxide ion and singlet oxygen were generated by M-TCPP-La and involved in selective oxidization of CEES to 2-chloroethyl ethyl sulfoxide (CEESO). Notably, a very short half lifetime (2.5 min) was achieved using Fe-TCPP-La as the photocatalyst. In comparison to currently utilizing singlet oxygen and hydrogen peroxide as oxidizing agents, this work employing both singlet oxygen and superoxide ion represents a new and effective strategy of detoxification of mustard gas.

Metal-organic cages are potential artificial models for mimicking biological functions due to their capability of selective encapsulation for certain guest molecules. In this work, we designed and synthesized a series of rhombic dodecahedral Ni-imidazolate cages (Ni

A pair of enantiomers of three-dimensional (3D) chiral coordination polymers (CCPs) were successfully constructed by using achiral components 4,2':6',4''-terpyridyl precursors and Cu2+ through spontaneous resolution (1 a). By utilising feeding controlled chiral-templated induction and chiral auxiliary behaviour of optically pure camphor sulfonate (CSA), the enantioenriched (1 b-P and 1 b-M) and CSA captured (1 c-P and 1 c-M) CCPs were successfully synthesised, respectively. The chiral information of the corresponding products was confirmed by X-ray single crystal diffraction and solid-state CD spectra. Meanwhile, the formation processes of 1 b-P and 1 b-M were monitored through solution CD spectra, UV/Vis spectra and ESI-TOF MS. Based on these results, a reasonable chiral-templated induction mechanism of forming 1 b-P and 1 b-M was proposed.

A variety of planar organic fluorophores (R=phenyl, naphthalenyl, pyrenyl) and luminescence promotors (X=Cl, Br, I) were equipped, respectively, on the alternatively arranged vertices of cubic ZnII -imidazolate cages through orthogonal subcomponent self-assembly. It was found that supramolecular interactions, especially weak C-H⋅⋅⋅X interactions, play a key role in activating an efficient radiative pathway, coupled with reduced nonradiative decay rate through metal coordination, therefore significantly boosting the emission quantum yields of the system. This finding provides a strategy that utilizes molecular geometry and supramolecular interactions to modulate the emission efficiency of luminescent cage-based materials.

Using water as the sole solvent, the bifunctional molecule tetrakis(methylthio)-1,4-benzenedicarboxylic acid (TMBD) was reacted with Cu(CH3CN)4BF4 to form a robust microporous metal-organic framework (MOF, CityU-7) featuring Cu(I) ions being simultaneously bonded to the carboxyl and thioether donors. The MOF solid is stable in air and can be easily activated by heating, without the need for treatment with organic solvents. The subnanoscopic pores (ca. 0.6 nm) of the host net allow for uptake of CO2 and H2O but exhibit lesser sorption for N2 at 77 K. The microporous net can also be penetrated by I2 molecules.

Three coordination polymers (CPs) with square-planar CuII/NiIIN4 subunits were formed in one step by subcomponent self-assembly, giving rise to an unprecedented linking variety of in situ embedded metalloligands and CuI clusters. All CPs exhibit unusual visible-light adsorption. Enhanced photocatalytic activity and high selectivity were observed in the oxidation of benzene under visible-light irradiation.

A family of gyroidal metal-organic frameworks (STUs) composited with transition metal ions and bi-imidazolate ligands (BIm) were prepared and applied as both Lewis base and acid catalysts. Benefiting from the intrinsic basicity of the ligands and the Lewis acidic sites of the open metal centres, the STUs materials show excellent catalytic activities as Lewis base for the Knoevenagel condensation reaction between various aldehydes and malononitrile, and as Lewis acid for cyanosilylation reactions. Among these STUs, STU-4 (Ni(BIm)) shows the best catalytic efficiency (conversions >99 %) in both Knoevenagel condensation and cyanosilylation reactions under mild conditions, providing thus an advanced material for both Lewis base and Lewis acid catalysis.

A series of cubic cobalt-imidazolate cages have been successfully synthesized via subcomponent self-assembly in different solvents under solvothermal conditions. The homovalent CoII and mixed-valence CoIII,II-imidazolate cages are assembled with control over the mixed solvent ratio of N,N-diethylformamide/ethanol, respectively.

A novel isohedral 3-periodic net (i.e. a net with one kind of tile), showing a Cairo pentagonal tiling projection on the Euclidean plane, has been identified in a series of site-modified CuCN/CuSCN networks, namely, [Cu6 (SCN)2 (CN)6 ⋅Ni(tpy)2 ]n (1), [Cu6 (SCN)(CN)7 ⋅Ni(tpy)2 ]n (2) and [Cu6 (CN)8 ⋅Ni(tpy)2 ]n (3) (tpy=2,2':6'',2''-terpyridine). These infinite inclusion compounds were prepared via a solvothermal sulfur migration reaction with subtle modification to fine-tune the sulfur content. The chiroptical activity of single crystals, which arises from the intrinsically chiral net, was confirmed by X-ray diffraction and solid-state circular dichroism spectra.

Chiral coordination cages feature both chirality and defined inner space, providing advanced molecular materials. A series of chiral 20-nucleus cobalt-imidazolate cages were synthesized by self-assembly of 72 subcomponents, featuring a novel tetartoid (tetragonal pentagonal dodecahedron) structure. Spontaneous resolution of racemic tetartoidal cages (Δ and Λ) into a conglomerate of homochiral crystals are observed, while both homochiral Δ and Λ tetartoidal cages can be obtained through chiral induction of (d)- and (l)-enantiomers of menthol, respectively. The 2-methyl substituent on imidazolyl is critical to the formation of a tetartoidal cage, and the absence of such steric effect will switch the final structure to a cubic cage.

Two one-dimensional (1D) helical coordination polymers, CuBIm–Cl and CuBIm–Br (BIm = 1,2-bis((5H-imidazol-4-yl)-methylene)hydrazine), are constructed from Cu2+ ions, halides and mono-deprotonated BIm. Solid-state crystalline conversions of CuBIm–Cl and CuBIm–Br to a gyroidal metal–organic framework (MOF) STU-3 which is composed of Cu ions and Bim ligands are observed through a gas–solid reaction, where the gas is methylamine.

Cigarette smoking is one of the most significant public health issues and the most common environmental cause of preventable cancer deaths worldwide. EGFR (Epidermal Growth Factor Receptor)-targeted therapy has been used in the treatment of LC (lung cancer), mainly caused by the carcinogens in cigarette smoke, with variable success. Presence of mutations in the KRAS (Kirsten rat sarcoma viral oncogene homolog) driver oncogene may confer worse prognosis and resistance to treatment for reasons not fully understood. NQO1 (NAD(P)H:quinone oxidoreductase), also known as DT-diaphorase, is a major regulator of oxidative stress and activator of mitomycins, compounds that have been targeted in over 600 pre-clinical trials for treatment of LC. We sequenced KRAS and investigated expression of NQO1 and five clinically relevant proteins (DNMT1, DNMT3a, ERK1/2, c-MET, and survivin) in 108 patients with non-small cell lung carcinoma (NSCLC). NQO1, ERK1/2, DNMT1, and DNMT3a but not c-MET and survivin expression was significantly more frequent in patients with KRAS mutations than those without, suggesting the following: (1) oxidative stress may play an important role in the pathogenesis, worse prognosis, and resistance to treatment reported in NSCLC patients with KRAS mutations, (2) selecting patients based on their KRAS mutational status for future clinical trials may increase success rate, and (3) since oxidation of nucleotides also specifically induces transversion mutations, the high rate of KRAS transversions in lung cancer patients may partly be due to the increased oxidative stress in addition to the known carcinogens in cigarette smoke.

Light oxygenates, such as methyl lactate (MLA), methyl levulinate (MLE), methyl formate (MFO), methyl acetate (MAC), dimethoxymethane (DMM), and methoxyacetaldehyde dimethyl acetal (MADA) were synthesized from cellulose in the presence of promoted SnX2 (X = Cl−, Br−, and I−) salt catalysts in methanol. The presence of halides in SnX2-MLn (MLn is metal salt) catalysts was found crucial for methyl lactate formation from sugar. The investigation shows that ZnCl2 is an efficient promoter for SnX2 catalyst in converting cellulose to light oxygenates. Up to 52.2% of total one-pass oxygenate yield was obtained in the presence of SnCl2–ZnCl2 catalyst.

Reported here is a new CdII-based metal–organic framework (MOF), ROD-8, based on the rod secondary building unit (SBU) and tetratopic linker 1,3,6,8-tetrakis(p-benzoic acid)pyrene. The structure of this MOF experiences framework disorder with the two extreme ordered orientations of the ligand, which are topologically related to the two nets, namely lrk and lrl, both derived from the basic net lrj. Moreover, the activated sample, ROD-8a, shows selective gas adsorption of CO2 over N2, CO2 over CH4 and CH4 over N2 at room temperature, estimated by the Ideal Adsorbed Solution Theory (IAST).

A series of neutral cubic nickel(II)-imidazolate Ni8L12X4 cages were prepared by rational choices of substituents and anions with solvothermal subcomponent self-assembly technology. Both substituents and halide anions play a critical role in the formation and stabilization of cubic cages. Changing one of the factors in the reaction will switch the final structure to a Ni14L24 rhombic dodecahedral cage. The cubic cage can transform to a large rhombic dodecahedral cage in the presence of methylamine at room temperature accompanied by a color change from purple to light yellow.

In this work, investigation of the comparative influence of diverse ionic liquids (ILs) as electrolyte additives on the chiral separation of dansylated amino acids by using Zn(II)-L-arginine complex mediated chiral ligand exchange CE (CLE-CE) was conducted. It has been found that not only the varied substituted group number, but also the alkyl chain length of the substituted group on imidazole ring in the structure of ILs show different influence on chiral separation of the analytes in the CLE-CE system, which could be understood by their direct influence on EOF. Meanwhile, the variation of anion in the structure of ILs displayed remarkably changed performance and the ILs with Cl(-) showed the most obvious promoting effect on the chiral separation performance. Among the investigated seven ILs, 1-butyl-3-methylimidazolium chloride was validated to be the proper electrolyte additive in the CLE-CE system. Moreover, it has been observed that 1-butyl-3-methylimidazolium chloride also has obvious promotive effect on the labeling performance. The results have demonstrated that the ILs with different structures have important relation to their performance in CLE-CE and to their labeling efficiency in dansylation of the analytes.

A new β-diketone ligand, 1-(4-ethyl-4H-thieno[3,2-b]indol-6-yl)-4,4,4-trifluoro-butane-1,3-dione(HL) was synthesized by four steps reaction (Suzuki–Miyaura cross-coupling, Cadogan cyclization, N-ethylation and Claisen condensation reaction) from 1-(4-bromo-3-nitrophenyl)ethanone and thiophen-2-ylboronic acid. Deprotonated ligand (L−1) and 1,10-phenanthroline (phen) coordinated to Eu3+ to obtain a new europium (III) complex, EuL3(phen). The complex was characterized by elementary analysis, IR, 1H NMR, UV–Visible absorption spectroscopy, thermogravimetric analysis (TGA) and photoluminescence (PL) measurements in detail. TGA shows that the decomposition temperature of the complex is up to 320 °C. PL measurement results indicate that the Eu(III) complex exhibit intense red-emission with the characteristic of europium ion. Red LED device was successfully fabricated by employing the complex onto 380 nm-emitting InGaN chip, which shows that the complex can act as red phosphor in combination with 380 nm-emitting chips.

The catalytic disproportionation of glycerol was investigated over active carbon (AC) supported catalysts. Typically, 1,2-propanediol, acetic acid, and acetaldehyde were found as the major products of the reaction over catalysts Na2CO3/AC and K2CO3/AC. Other products, such as methanol, ethanol, ethylene glycol, and acetone were also formed as the minor products in the reaction. All of these compounds are defined as oxygenate products (OP). The highest OP yield of 65.3% (carbon mol) was obtained over Na2CO3/AC at 593 K.

A new β-diketone ligand, 1-(9-ethyl-6,8-dimethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dione was synthesized by four step reaction (Suzuki–Miyaura cross-coupling, Cadogan cyclization, N-ethylation and Claisen condensation reaction) from 1-(4-bromo-3-nitrophenyl)ethanone and 3,5-dimthylphenylboronic acid. Deprotonated 1-(9-ethyl-6,8-dimethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dionate (L −1 ) and 1,10-phenanthroline (phen) coordinated to europium ion to yield a new europium(III) complex, EuL 3 [phen]. The Eu(III) complex was characterized by elementary analysis, IR, 1 H NMR, 13 C NMR , UV–Vis absorption spectroscopy, thermogravimetric analysis (TGA) and photoluminescence measurements. TGA shows that the decomposition temperature of the complex EuL 3 [phen] is up to 320 °C. Photoluminescence measurement results indicate that the Eu(III) complex exhibits intense red emission and extends its excitation band blue light region. Red emission LEDs were successfully fabricated by precoating complex EuL 3 [phen] onto 460 nm blue-emitting InGaN chip. The europium complex based on depronated 1-(9-ethyl-6,8-dimethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dionate is a very interesting blue light excitable red emission material, which can be applied in many fields without UV radiation.

A new catalytic process for p-xylene synthesis from the methylation of toluene with CH3Br was proposed. CH3Br was prepared from the catalytic bromination of natural gas (CH4), by using H2O + HBr + O2 as mediator over supported Rh catalyst. The methylation conditions were investigated using HZSM-5 or modified HZSM-5 catalyst. Under optimal reaction conditions, p-xylene selectivity is up to 93%, and p-xylene yield is more than 21% at 673 k over the Si—P modified HZSM-5 catalyst. Compared to the processes using MeOH or dimethyl carbonate (DMC) as methylation agent, this new process is very attractive in an economic standpoint since CH4 is much cheaper than MeOH and DMC. In addition, the process has other advantages, such as mild reaction conditions, simple operation, high-product yield, and so on. It is predicted that the process has good industrial potential for para-xylene production. © 2012 American Institute of Chemical Engineers AIChE J, 59: 532–540, 2013

Phenol was synthesized from the hydroxylation of bromobenzene, which was prapared by reacting benzene with bromine. In the benzene bromination reaction, HZSM-5 (Si/Al = 400/1) was found to be a stable catalyst, which catalyzed the stoichiometric reaction of benzene with bromine. More than 90% of bromobenzene selectivity was reached over HZSM-5 and the byproduct was dibromobenzenes. In the second reaction, bromobenzene reacted with a cataloreactant to form metal bromide and phenol. This is a catalytic as well as stoichiometric reaction between bromobenzene and the metal oxide. It was found that only the supported highly dispensed metal oxide was reactive to the bromobenzene hydroxylation reaction. In this investigation, 10mol%CuO/SiO2 was found to be the most active cataloreactant for bromobenzene hydroxylation reaction.

By systematically varying the geometric length and electronic properties of the second ligating ligands of halogen (Cl(-), Br(-), and I(-)) and pseudohalogen (CN(-), SCN(-), and N(3)(-)) anions, we synthesized 11 isomeric/isostructural copper(I) complexes: [Cu(2)(L3-3)I](n) (1), [Cu(2)(L4-4)Br](n) (2-Br), [Cu(2)(L4-4)Cl](n) (2-Cl), [Cu(2)(L3-4)(CN)](n) (3), [Cu(2)(L3-3)(CN)](n) (4), [Cu(3)(L4-4)(CN)(2)](n) (5), {[Cu(2)(L4-4)Br](2)·CuBr}(n) (6-Br), {[Cu(2)(L4-4)Cl](2)·CuCl}(n) (6-Cl), [Cu(2)(L4-4)(SCN)](n) (7α-SCN), [Cu(2)(L4-4)(SCN)](n) (7β-SCN), and [Cu(2)(L4-4)(N(3))](n) (7α-N(3)). These structures are based on a series of isomeric pyridylpyrazole ligands, namely, 3,5-bis(3-pyridyl)-1H-pyrazole (HL3-3), 3-(3-pyridyl)-5-(4-pyridyl)-1H-pyrazole (HL3-4), and 3,5-bis(4-pyridyl)-1H-pyrazole (HL4-4), and their structural features range from 1-D (1), 2-D (2), and 3-D noninterpenetration (3), to 3-D 2-fold interpenetration (4 and 5), to 3-D self-catenation (6 and 7), exhibiting a trend from simple to complex with dimension expansion and an interpenetrating degree increase. The five most complex structures (6 and 7) with self-catenated networks are based on 2-fold interpenetrated networks linked via appropriate second ligating spacers (Cl(-), Br(-), SCN(-), and N(3)(-)), representing a strategy to construct self-catenated coordination polymers through cross-linking interpenetrated frameworks. Moreover, these complexes exhibit strong photoluminescence, which is mainly ascribed to Cu(I)-related charge transfers (MLCT, MC, and MMLCT) regulated by the electronic properties of halogen or pseudohalogen. The topological evolution and luminescence variation presented in this work open an avenue to understanding the luminescence origin and the structure-property relationship of luminescent coordination polymers.

The disproportionation reaction of glycerol over NaOH was reported in this article. The effects of reaction temperature, glycerol to NaOH mol ratio, glycerol concentration in calcium carbonate, and reaction time were investigated. Under the optimum conditions, 82.6% of glycerol conversion with 44.6% of total alcohol selectivity (propylene glycol, ethylene glycol, methanol, and ethanol) was obtained.

A Mn-based rod metal-organic framework (MOF), ROD-6, with a new lrk net is synthesized. It represents an unusual type of MOF topology containing both a 1-periodic secondary building unit (rod SBU) and a polytopic linker (here 1,3,6,8-tetrakis(p-benzoic acid)pyrene), and also exhibits high stability (up to 485 °C) and unusual CO2 uptake behaviour and selectivity despite the lack of strong interacting sites, demonstrated by the low and increasing heat of adsorption.

This paper reports the fabrication of a hyper-elastic pressure transducer by embedding silicone rubber with micro-channels of conductive liquid metal eGaIn. Micro-channels with dimensions being as small as 300 µm are fabricated by a maskless soft lithography technique. The core of the sensor consists of three layers: the buffer area (top layer), the PDMS membrane layer (middle layer), and the microfluidic layer (bottom layer). Pressures applied on the surface of the elastomer deform the underlying channels and change the electrical resistance. Owing to the arrangement of the buffer strip, stress concentration in the vicinity of micro-channels is eliminated or distinctly reduced compared to the previous studies. At the same time, the stress tends to be more uniform and a certain degree of reduction is emerged at the microfluidic layer. The effects of the buffer zone are well validated by ANSYS workbench. Meanwhile, by adopting trapezoid geometry of micro-channels and the segmented statistical calibration method, the calibration curves and equations are obtained with better linearity and lower hysteresis. Besides, the spring steel shell (50CrVA) with high yield strength is used to bear the primary pressure together with peripheral parts composed of silica gel with good elastic property, which increases effectively the range of the flexible pressure sensor. Finally, theoretical predictions are conducted based on elasticity and contact mechanics. The experimental measured data are in good agreement with the theoretical results.

The microstructure and properties of ternary boride ceramic coating prepared by reactive flame spraying on surface of H13 steel are studied as well as the microstructures, microhardness, wear resistance and thermal fatigue resistance of the coating. The results show that the Mo2FeB2 cermet coating by reactive flame spraying has good wear resistance and thermal fatigue resistance and its microhardness can even reach 1200 HV.

A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the catalytic performance of the solid bases was evaluated. Both the reaction temperature and time can affect the yield of lactic acid. A high yield (97%) of lactic acid was achieved under the optimal reaction condition. The 1H NMR spectra and HPLC-MS were used to identify the formation of the lactic acid and variations of ionic liquid. It is found that ionic-liquids have a unique solvent effect for glucose and bases. Water can be used as solvent to extract calcium lactate. This shows a great potential of hydrophobic ionic liquids in the solid bases catalyzed reaction that is limited by the weak solubility of solid bases in organic and water solution.

The catalytic conversion of CH 3 Br to aromatics was investigated over PbO-modified HZSM-5. The effects of PbO loading, SiO 2 /Al 2 O 3 molar ratio of HZSM-5, and calcination conditions of catalyst on catalytic performance were studied. It was found that the most suitable PbO loading and SiO 2 /Al 2 O 3 ratio are 5 wt% and 70, respectively. The 5 wt% PbO/HZSM-5 calcined at 450 °C for 8 h performs the best. Also, PbO is superior to the other metal oxides selected to modify HZSM-5, and HZSM-5 is better than SiO 2 , Al 2 O 3 or ZrO 2 as support. The characterization results indicate that (i) the PbO species is highly dispersed on the HZSM-5 support, (ii) the role of PbO is to promote hydrocarbon aromatization, and (iii) the acid sites of HZSM-5 are indispensable for CH 3 Br conversion into aromatics. We found that the deactivation of catalyst is due to pore blocking by carbonaceous deposits. The overall results demonstrate that the method is efficient for the conversion of CH 4 to aromatics.

Trans-1,2-cyclohexanediol was synthesized from the oxidation of cyclohexene. The t-butyl hydrogen peroxide (TBHP) was used as oxidant. High cyclohexene conversion (93%) with high 1,2-cyclohexanediol selectivity (98.2%) was obtained over MoO3. Among the tested metal oxide catalysts MoO3, VO5, Nb2O5, Cr2O3, and WO3, MoO3 was found to be the most active catalyst for the oxidation of cyclo-olefins to prepare 1,2-diols. Except cyclohexene oxidation, MoO3 was also found to be active for the oxidation of other cyclo-olefins.

Recent progress in cancer biology research has shown that abnormal proliferation in tumor cells can be attributed to aberrations in cell cycle regulation, especially in G₁ phase. During the course of searching for microbial metabolites that affect cell cycle distribution, we have found that simaomicin α, a polycyclic xanthone antibiotic, arrests the cell cycle at G₁ phase. Treatment of T-cell leukemia Jurkat cells with 3 nM simaomicin α induced an increase in the number of cells in G₁ and a decrease in those in G₂–M phase. Cell cycle aberrations induced by simaomicin α were also detected in colon adenocarcinoma HCT15 cells. Simaomicin α had antiproliferative activities in various tumor cell lines with 50% inhibitory concentration values in the range of 0.3–19 nM. Furthermore, simaomicin α induced an increase in cellular caspase-3 activity and DNA fragmentation, indicating that simaomicin α promotes apoptosis. The retinoblastoma protein phosphorylation status of simaomicin α-treated cell lysate was lower than that of control cells, suggesting that the target molecule of simaomicin α is in a pathway upstream of retinoblastoma protein phosphorylation. In the course of evaluating polycyclic xanthone antibiotics structurally related to simaomicin α, we also found that cervinomycin A1 stimulated accumulation of treated cells in G₁ phase. These results indicate that the polycyclic xanthones, including simaomicin α and cervinomycin A1, may be candidate cancer chemotherapeutic agents.

Methyl bromide was synthesized by reacting methane with oxygen and hydrogen bromide over Rh/SiO2 catalyst. The reaction started from the oxidation of HBr to form active bromine species (Br• radicals and Br* surface species), which in turn reacted with CH4 to form CH 3 • radicals and $$\hbox{CH}_{3}^{\ast}$$ surface species. These CH 3 • and $$\hbox{CH}_{3}^{\ast}$$ species reacted with the active bromine species to form CH3Br and CH2Br2. The presence of HBr inhibited the deep oxidation and the steam reformation of CH4 and therefore, guaranteed the high selectivity of CH3Br. In the presence of HBr, CO was formed from the oxidation and steam reformation of CH3Br, while CO2 was formed from the oxidation and steam reformation of CO over Rh/SiO2 at reaction temperature higher than 560 °C.

The metal oxide V 2 O 5 (band gap 2.0 eV) is potentially active in solar light for photocatalysis reactions. However, the rapid electron–hole pair recombination makes it inactive. The doping of V 2 O 5 into MgF 2 (band gap 6.2 eV) matrix reduces the recombination rate of electron–hole pairs and makes VO x /MgF 2 have high photon quantum efficiency (3.2% at 578 nm over 9.1%VO x /MgF 2 for acetone oxidation). The Pt doped 9.1%VO x /MgF 2 catalysts had even higher photon quantum efficiency (34.6% at 578 nm) for acetone oxidation. The VO x /MgF 2 and Pt doped VO x /MgF 2 catalysts were also proved to be active for methanol, ethanol, and benzene photodegradation.

This paper reports on the strong tendency of a group of thioether and selenoether molecules to adopt non-centrosymmetric and non-interpenetrating features in forming 3D coordination networks with metal ions. We illustrate such tendency with the (10, 3)-a nets formed by Ag(I) ions and the large aromatic ligands of 1,3,6,8-tetrakis(phenylseleno)pyrene (TPhSeP) and 2,3,6,7,10,11-hexakis(phenylseleno)triphenylene (HPhSeT). In particular, TPhSeP interacts with AgSbF6 to provide a 3D chiral network based on trimeric coordination building blocks. Each trimeric building block is rather complex and consists of three pairs of TPhSeP molecules integrated through the Ag+ ions into a circular unit. The circular, trimeric units function as the three-connected nodes, which are further connected through the Ag+ ions to generate the (10, 3)-a topology. By comparison, the connectivity of the HPhSeT-based net is simpler, with the trigonal-shaped HPhSeT molecules acting as three-connected nodes that are integrated into a (10...

This work focuses on the investigation of the influence of metal ions and supramolecular interactions on the self-assembly of in situ generated tetrazolate coordination architectures. A series of new metal−organic complexes, [Zn(pzta)2(H2O)2] (1), [Cu(pzta)2](H2O)3 (2), [Cd(pzta)2]n (3), [Ag(pzta)]n (4), and [Cd2(pzta)(OH)(SO4)]n (5) [pzta = pyrazinyl tetrazolate], have been achieved by the in situ hydrothermal reactions of pyrazinecarbonitrile, sodium azide, and different metal ions. Complexes 1 and 2 have similar mononuclear structures bearing distinct intermolecular hydrogen-bond interactions to form two different 3D supramolecular networks based on 44-subnets. Complex 3 features a 1D crossed-shape chain structure. Complex 4 is a coordination polymer comprised of mildly undulated 2D layers with a (4.82) topological network. Complex 5 is a 3D diamondoid framework constructed by pentanuclear cadmium cluster nodes and pzta linkers. The configurations of complexes 1−5 span from mononuclear (1, 2), to one-d...

Quaternary ammonium salts were synthesized from ammonium salts and dialkyl carbonates over imidazolium ionic liquid catalysts. The reaction gave almost stoichiometric amounts of the quaternary ammonium salts for halides and nitrates. It was found that the electron-donating property of the alkyl moieties of ammonium cations, the electrophilic nature of the alkyl group of the carbonate, the acidity of the acid that the anion of the ammonium salt corresponds to, and the steric hindrance of the ammonium salts and the dialkyl carbonates are the key factors that influence the yields of quaternary ammonium salts. Strong electron-donating alkyl groups on the nitrogen atom of the ammonium salt, electron-withdrawing groups on the methylene carbon of dialkyl carbonate, and weaker steric hindrance of the starting ammonium salts and dialkyl carbonates favor the alkylation reaction of ammonium salts.

Styrene was oxidized by molecular oxygen over TiO 2 and TiO 2 /SiO 2 for the formation of benzaldehyde. In the absence of catalyst at 100 °C and 10 atm O 2 , polystyrene is the major product. Over the catalysts, the oxidation of styrene is enhanced with benzaldehyde and formaldehyde being the major whereas phenylacetaldehyde, acetophenone, styrene oxide, benzoic acid, and polymer being the minor products. The polymerization of styrene was initiated by the radicals formed in the oxidation reaction. The addition of radical inhibitor nitrobenzene and/or the employment of a catalyst of high specific surface area can promote the termination of the radicals, and hence improve the selectivity of benzaldehyde.

Suppression of nuclear factor-kappaB (NF-kappaB)/inhibitor of nuclear factor-kappaB (IkappaB) signaling pathway is a potential property of thalidomide. This study was designed to investigate the effects of thalidomide on expressions of NF-kappaB, IkappaB and intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule (VCAM-1) in established rat liver cirrhosis.Rat liver cirrhosis was achieved by IP injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. CCl4 was then discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Hydroxyproline (HYP) content in liver was detected by biochemical assay. NF-kappaBp65, ICAM-1, VCAM-1 and alpha-smooth muscle actin (alpha-SMA) protein in the liver, IkappaBalpha protein in cytoplasm and NF-kappaBp65 protein in nucleus and ICAM-1, VCAM-1 mRNA levels in the liver were studied using immunohistochemistry, Western blot, and reverse transcriptase polymerase chain reaction, respectively.Compared with the spontaneous recovery of cirrhosis, the histopathology of liver of rats given thalidomide was significantly improved. HYP content in liver, the expressions of ICAM-1, VCAM-1 mRNA and protein, NF-kappaBp65 and alpha-SMA protein were decreased significantly and IkappaBalpha protein in liver was elevated significantly in this group.Thalidomide may exert its effect on downregulation of NF-kappaB-induced adhesion molecules and activation of hepatic stellate cell via inhibition of degradation of IkappaB to reverse established rat hepatic cirrhosis.

A series of Ni-imidazolate cubic cages, one-dimensional and two-dimensional coordination polymers based on the cubic cages, have been prepared by solvothermal subcomponent self-assembly of 5-methyl-4-formylimidazole, m-xylylenediamine, and Ni(II) salts with varied anions. These compounds have been characterized by single-crystal X-ray diffractions, elemental analysis, IR spectra, and powder X-ray diffractions. The formation of an oligomerized coordination cage or an infinite coordination polymer depends on the anions chosen. An oligomerized 8-nuclear Ni-imidazolate cubic cage is formed when the anion Cl(-), Br(-), I(-), SCN(-), NO2(-), or NO3(-) is utilized in the reactions, and a two-dimensional coordination polymer based on the Ni-imidazolate cubic cage will be obtained when N3(-), (CN)2N(-), or (CN)3C(-) act as the anions. When only ClO4(-) or both ClO4(-) and [Ni(C4N2S2)2](2-) (C4N2S2 = dimercaptomaleonitrile) as anions exist in the reaction mixture, a ladder-like one-dimensional coordination polymer based on the Ni-imidazolate cubic cage and formate is formed unpredictably.

A combination of trastuzumab and cisplatin or trastuzumab and capecitabine has been confirmed to be effective for treating adverse effects in with HER2-positive advanced gastric cancer (AGC) patients. We retrospectively compared the activity and safety of trastuzumab plus cisplatin (HP) and trastuzumab plus capecitabine (HX) for elderly HER2-positive AGC patients. Ninety two HER2-positive AGC patients were included in this study; of those 48 patients received trastuzumab (course 1, 8 mg/kg followed by course 2, onward, 6 mg/kg on day 1) plus cisplatin (60 mg/m2) intravenously on day 1 of a 3-week cycle and 44 patients received trastuzumab (course 1, 8 mg/kg; course 2 onward, 6 mg/kg) plus intravenous oral capecitabine (1000 mg/m2 twice daily on days 1–14), every 3 weeks. The primary end point was overall survival (OS). The secondary end points included objective response rate (ORR), progression-free survival (PFS), and toxicity. The median age was 71 years in both groups. The median OS was 15.5 months in the HP group and 17.0 months in the HX group, with no significant difference between the 2 groups (P = 0.78). There were also no significant differences in PFS (median 6.6 months vs 7.2 months, respectively; P = 0.90) and ORR (58.3% vs 59.1%, respectively; P = 1.00) between the HP group and the HX group. The major grade 3 or 4 adverse events in the HP group and the HX group were neutropenia (35.4% vs 29.5%, respectively), followed by anorexia (25.0% vs 22.7%, respectively), and anemia (16.7% vs 13.6%, respectively), no significant differences were observed. HP and HX were associated with similar efficacy and safety in HER2-positive AGC patients.

This study investigated the effect of thalidomide on oxidative stress in rat liver cirrhosis. The cirrhosis of rat was induced by intraperitoneal injection of carbon tetrachloride thrice weekly; meanwhile, thalidomide (10mg/kg or 100mg/kg) was given daily by intragastric administration for 8 weeks. The content of oxidative stress parameters, including superoxide dismutase, glutathione peroxidase, and malondialdehyde, in the liver was detected by biochemical assay. Immunohistochemistry revealed alpha-smooth muscle actin (alpha-SMA), desmin, and tissue inhibitor of metalloproteinase-1 (TIMP-1) protein in the liver. Nuclear factor kappa B p65 (NF-kappaBp65) protein in nucleus and transforming growth factor beta1 (TGF-beta1) protein in cytoplasm were detected by Western blot. NF-kappaBp65, TGF-beta1, and TIMP-1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction. Liver histopathology was significantly improved in rats given high doses of thalidomide. The content of oxidative stress parameters and the expressions of NF-kappaBp65, TGF-beta1 and TIMP-1 protein, and mRNA were significantly decreased in these animals. The expressions of alpha-SMA and Desmin protein were also significantly decreased in them. Thalidomide might exert an effect on the inhibition of oxidative stress via downregulation of NF-kappaB signaling pathway to prevent the progression of liver cirrhosis.

Alkanes such as iso-butane, n-pentane, and cyclohexane have been converted effectively to maleic anhydride, 2-methyl maleic anhydride, and acetic acid over MoVO catalysts below 330 °C. In order to explore the possible reaction pathways, the oxidation of iso-butene, cyclohexene, 2-methyl-1-propanol, tert-butanol, and 2-methylacrylic acid were examined over the catalysts. In iso-butene oxidation, acetic acid and 2-methyl maleic anhydride were detected but not maleic anhydride. In cyclohexene oxidation, benzene and phenol were detected as major products but it was not the case in cyclohexane oxidation. The results of our investigation indicate that the oxidation pathway of iso-butane is different from that of iso-butene, 2-methyl-1-propanol, tert-butanol, and 2-methylacrylic acid, whereas the oxidation pathway of cyclohexane is different from that of cyclohexene.

Seven copper complexes [Cu(L1)I2] (1), [Cu2(L1)2I2]2[Cu2(μ-I)2I2] (2), [Cu(L2)I2] (3), [Cu2(L2)(μ-I)I(PPh3)] (4), [Cu4(L2)2(μ-I)2I2] (5), {[Cu(L2)I]2[Cu2(μ-I)2I2]}n (6) and [Cu2(L2)(μ-I)2]n (7) have been prepared by reactions of ligands: 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L1) and 4′-(3-pyridyl)-2,2′:6′,2″-terpyridine (L2) with CuI in hydrothermal conditions, respectively. By alternating the oxidations states of the metal centers, increasing stoichiometric metal/ligand ratio and introducing a second ligand, the compounds, were successfully developed from mononuclear (1 and 3) to multinuclear (2, 4 and 5) and polymers (6 and 7). The synthesis of these compounds may provide an approach for the construction of coordination compounds of 4′-pyridyl terpyridine with different nuclearity.

The reactions of 2,4,6-tri(2-pyridyl)-1,3,5-triazine (tpt) with copper(I) halides under solvothermal or traditional conditions yielded two polymeric Cu(I) complexes [Cu2I2(tpt)]n (1) and [Cu3I3(tpt)]n (2), one mixed-valence Cu(I)-Cu(II) complex [Cu4Cl2I4(tpt)2] (3), and two Cu(II) complexes [CuBr(bpca)] (4) and [CuI(bpca)] (5) (bpca = bis(2-pyridylcarbonyl)amine). Complex 1 is a zigzag chain with tpt in a bis-bipyridine-like coordination mode, whereas complex 2 with tpt chelating three Cu(I) cations is a ladderlike coordination polymer. Complex 3 is mixed-valence, with Cu(I) in a distorted tetrahedral geometry and Cu(II) in a distorted square pyramidal geometry, forming a ladderlike supramolecular chain. Complexes 4 and 5 are the products of in situ hydrolysis of tpt involving the oxidation of Cu(I). The synthesis and characterization of complex 1, 2, and 5 indicated that Cu(I) cannot promote the hydrolysis of tpt. The theoretical study shows that the main effect for hydrolysis of tpt is the electron-withdrawing effect of metal ions.

Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties.

A high throughput fluorescence photo-imaging method has been developed for the screening of photo-degradation catalysts. When employed to analyze the photo-degradation of 1,6-hexamethylenediamine (the probe molecule), the method produced results that are comparable to that when methyl orange was employed as a probe molecule and UV spectrometry as an analysis device. We found that the variation trends in catalytic activity over the same group of catalysts are the same in both cases. The results indicate that the fluorescence photo-imaging method is applicable to the screening of photo-degradation catalysts. For comparison, mesoporous catalysts of high specific surface area prepared by using P123 (HO(CH 2 CH 2 O) 20 (CH 2 CH(CH 3 )O) 70 (CH 2 CH 2 O) 20 H) as a template and “regular” catalysts (those prepared without P123) were tested. The results showed that most of the former catalysts are superior to the latter counterparts. Our study also revealed that the addition of ZrO 2 to TiO 2 did not result in significant improvement in catalytic activities, whereas marked improvement was observed when Nb 2 O 5 or WO 3 was added to TiO 2 . When Nb 2 O 5 and WO 3 were co-doped to TiO 2 , the tertiary catalysts exhibited higher catalytic activities. The catalysts containing 20–30% of Nb 2 O 5 and 10–20% of WO 3 (balanced with TiO 2 ) are superior to any of pure TiO 2 , Nb 2 O 5 , WO 3 , and the binary catalysts composed of any two of TiO 2 , Nb 2 O 5 , and WO 3 . Our study has demonstrated that besides the traditional TiO 2 -domain catalysts, active photo-degradation catalysts can be prepared by combination of Nb 2 O 5 , WO 3 , and ZrO 2 .