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A collection of spirooxindole–cyclopentene–isoxazole hybrids bearing multiple chiral centers and various groups as potential MDM2–p53 inhibitors were designed and synthesized via a rarely reported organocatalytic 1,6-cycloaddition with exclusive α-regioselectivity. In vitro MDM2 binding and cytotoxicity assays showed that compound 4z was the most potent MDM2 inhibitor, while a mechanistic study indicated that oxidative damage and apoptosis in p53-wild colorectal cancer cells were induced. Molecular docking suggested that the H-bonds with Leu54 and pi stacking with His96 were crucial interactions between 4z and the substrate binding site of MDM2. This article demonstrates an efficient protocol to design and synthesize potent biologically active compounds, providing a basis for developing novel MDM2 inhibitors.

Helicobacter pylori (H. pylori) is one of the main factors that cause gastric lesions. The lotus leaf is an edible plant used in traditional Eastern medicine. This study evaluates the intervention effects of lotus leaf flavonoids (LLF) on gastric mucosal lesions in mice infected with H. pylori and explores their mechanism of action. High-performance liquid chromatography analysis reveals that LLF contain kaempferitrin (kaempferol-3,7-dirhamnoside), hypericin, astragalin (kaempferol-3-glucoside), phlorizin, and quercetin. LLF can reduce the number of gastric mucosal lesions and tissue lesions in mice with H. pylori-induced gastric lesions. LLF can increase the levels of somatostatin and vasoactive intestinal peptide in the serum of mice with gastric lesions and decrease the levels of substance P and endothelin-1 to inhibit gastric lesions. LLF can also reduce the levels of interleukin (IL)-6, IL-12, tumor necrosis factor (TNF)-α, and interferon-gamma cytokines in the serum of mice with gastric lesions. Using a quantitative polymerase chain reaction assay it can be seen that LLF can downregulate mRNA expressions of TNF-α, IL-1β, myeloperoxidase, keratin (KRT) 16, KRT6b, and transglutaminase 3 epidermal in the gastric tissues of mice with gastric lesions. Western blot analysis indicates that LLF can downregulate the protein expressions of caspase-1, Nod-like receptor protein 3, IL-1β, TNF-α, and Toll-like receptor 4 in the gastric tissues of mice with gastric lesions. LLF have beneficial effects on gastric lesions induced by H. pylori. Meanwhile LLF is more active in competition with ranitidine. LLF represent an active substance that can inhibit H. pylori-induced gastric lesions. The flavones of LLF may enhance the inhibition of gastric mucosal lesions by promoting the interaction between the compounds.

Fourteen avermectin B2a aglycon derivatives were designed and synthesized after removing the oleandrose disaccharide of avermectin B2a. Their structures were characterized by 1H NMR, 13C NMR, HMRS. Preliminary bioassays indicated that these compounds exhibited good insecticidal activity against diamondback moth at 200 mg/L, with mortality no less than 90%. Compounds 10b, 12a, 12c, 17 demonstrated good acaricidal activity against the adult mites, larvae, and good inhibition rate of hatching to mite eggs of Tetranychus cinnabarinus. Compounds 5, 10b, 10c exhibited excellent fungicidal activity against fourteen fungal pathogens in vitro. 3D-QSAR analysis showed that the fungicidal activity of avermectin B2a aglycon derivatives would be increased when a negatively charged and bulky group was introduced at 13-position, which will be instructive for the further modification of avermectin B2a aglycon.

Guar gum is an effective depressant of talc, but it also has some depression effect on sulfide minerals. To find new selective depressants, the depression effects and mechanisms of tragacanth gum to talc were studied and its role in the flotation separation of chalcopyrite from talc was investigated by flotation test, adsorption and zeta potential tests as well as XPS analysis. The individual mineral flotation test results showed that the natural flotability of talc is good which make it easy to be reported into the concentrate. The guar gum and tragacanth gum can effectively depress the flotation of talc, and their depression effect is not affected by pH. The mixed minerals flotation tests indicated that the tragacanth gum can effectively separate chalcopyrite from talc, both the copper concentrate grade and recovery are high, besides, tragacanth gum exhibits less depression effects for chalcopyrite compared with guar gum. According to the Zeta potential and XPS measurements, it can be concluded that tragacanth gum adsorbed on talc surface mainly through physical interactions, and hydrophobic interaction was considered as the main driving force and hydrogen bond may also play a role. Keywords: Talc, Depression, Tragacanth Gum, Chalcopyrite

Herein, we report that a gemini surfactant can efficiently separate KCl from NaCl by froth flotation to produce potassium fertilizer (KCl). For achieving the obviously superior flotation performance (KCl recovery increased by 14.51%), the dosage of the gemini surfactant should be three times less than that of the conventional monomeric surfactant. Its unique properties, such as double active centers to mineral surfaces, double hydrophobic groups, and stronger surface tension reducing ability, make it a superior flotation collector for separation of KCl from NaCl in potassium fertilizer production.

An important concept, the natural product derivatization method, was introduced and defined to comprehensively evaluate the significance of natural product derivatization in the design and development of pharmaceutical molecules. Therefore, based on the analysis of 464 new molecular entities registered for drugs worldwide from 2010 to 2018, the source, action mode, proportion of new active ingredients contained in “NP (natural product)” and “ND (natural product derivatives),” and structure–activity relationships were reviewed. Finally, the prospect of this method in the field of drug design is discussed.

In high fat diet-induced obese mice, the flavonoid derivative of tiliroside, Fla-CN, has antihyperglycemic effects, can improve insulin sensitivity, ameliorate metabolic lipid disorders, and benefits certain disorders characterized by insulin resistance. Fla-CN is a novel lead compound to discovery anti-diabetic and anti-obesity drugs. The present study reported the optimization of Fla-CN to obtain a new derivative, 10b, which has improved glucose consumption at the nanomolar level (EC50 = 0.3 nM) in insulin resistant (IR) HepG2 cells. 10b also increased the glycogen content and glucose uptake, and concurrently inhibited gluconeogenesis in HepG2 cells. Western blotting showed that 10b markedly enhanced the phosphorylation of AMPK (AMP-activated protein kinase) and AS160 (protein kinase B substrate of 160 kDa) and reduced the levels of the gluconeogenesis key enzymes PEPCK (phosphoenolpyruvate carboxykinase) and G6P (glucose 6-phosphatase) in HepG2 cells. The potential molecular mechanism of 10b may be activation of the AMPK/AS160 and AMPK/PEPCK/G6P pathways. We concluded that 10b might be a valuable candidate to discover anti-diabetic drugs.

In this study, a highly efficient fluorescent/phosphorescent white organic light-emitting device (WOLED) was fabricated using exciplex light emission. The hole-transport material 4,4ʹ,4ʺ-tris(N-carbazolyl)triphenylamine (TCTA), and electron-transport material, 4,7-diphenyl-1,10-phenanthroline (Bphen), were mixed to afford a blue-emitting exciplex. The WOLED was fabricated with a yellow phosphorescent dye, Ir(III) bis(4-phenylthieno [3,2-c] pyridinato-N,C 2 ʹ ) acetylacetonate (PO-01), combined with the exciplex. In this structure, the energy can be efficiently transferred from the blend layer to the yellow phosphorescent dye, thus improving the efficiency of the utilization of the triplet exciton. The maximum power efficiency of the WOLED reached a value 9.03 lm/W with an external quantum efficiency of 4.3%. The Commission Internationale de I'Eclairage (CIE) color coordinates ( x , y ) of the device were from (0.39, 0.45) to (0.27, 0.31), with a voltage range of 4–9 V.

The flotation separation of scheelite from calcite using sodium oleate as collector and acidified sodium silicate as depressant has been studied. The results show that sodium oleate has collecting ability to both scheelite and calcite and the flotation separation of scheelite from calcite cannot be realized if collector is used only. The depressant acidified sodium silicate has selective depression effect on calcite and the optimum ratio of sodium silicate to oxalic is 3:1. The use of acidified sodium silicate as depressant can achieve the flotation separation of scheelite from calcite. Infrared studies and zeta potential measurements showed that the pre-adsorption of acidified sodium silicate interferes with the adsorption of sodium oleate on calcite surface while does not interfere with its adsorption on scheelite surface.

The optical and barrier properties of thin-film encapsulations (TFEs) for top-emitting organic light-emitting diodes (TEOLEDs) were investigated using TFEs fabricated by stacking multiple sets of inorganic–organic layers. The inorganic moisture barrier layers were prepared by atomic layer deposition (ALD) of Al2O3 using trimethylaluminum (TMA) and O3 as precursors and are shown to be efficient barriers against gases and vapors. The organic alucone layers were produced by molecular layer deposition (MLD) using TMA and ethylene glycol as precursors. The [Al2O3:Alucone] ALD/MLD films were used because their adjustable inorganic–organic nanolaminate composition allows for the tuning of the optical properties, thereby enhancing their application potential for the design and fabrication of high performance light out-coupling structures for TEOLEDs. By carefully adjusting the relative thickness ratio of the inorganic–organic encapsulation materials, optimized light extraction was achieved and the films not only maintained their high moisture barrier strength but also showed excellent optical performance.

Changes in bamboo composition and microstructure following 60Co gamma (γ) ray irradiation were investigated by solid state 13C cross-polarization (CP) magic-angle spinning (MAS) spectroscopic nuclear magnetic resonance spectrometry (NMR) and a field emission scanning electron microscope (FESEM). The results indicated that irradiation doses lower than 100 KGy resulted in the degradation of hemicelluloses via scission of molecular chains, but there was also repolymerization and condensation in lignin. Irradiation doses higher than 100 KGy resulted in the degradation of cellulose, hemicelluloses, and lignin by significant oxidation reaction and partial scission of biopolymer chains to yield more small fragments with carbonyl groups.

Use of resource-rich wastepaper/recycled plastics as raw materials in the production of wood-plastic composites(WPC) can alleviate the shortage of wood resources, reduce pollution and has a attractive prospect. In this paper, old newspaper fiber(ONPF)/recycled-polypropylene(rPP) Wood-Plastics Composite(WPC) was prepared by means of mixing processing and compression molding. The effects of technical conditions on the mechanical properties of WPC were investigated. The structure of composite was characterized by means of FTIR and SEM. The results show that, Wastepaper and waste-PP can be used as raw materials for preparation of WPC. The suitable preparation process for wastepaper/rPP composites was: wastepaper fiber 20%, blending temperature 175°C, blending time 15min, molding pressure 12MPa, molding temperature 175°C and molding time 10min. In these conditions, tensile strength and flexural strength of wastepaper/rPP composites are 23.6MPa and 28.8MPa respectively, increased by 20.9% and 12.6% compared to those of rPP matrix. The elongation at break of WPC is 10.6%, and the flexural modulus is 1328.9MPa，increased by 7.7% compared to those of rPP matrix. The structure analysis found that there is no chemical reaction between the fibers and the matrix. The research results have important practical significance in the field of printing and packaging waste recycling and utilization, environmental protection and energy saving.

Scanning force microscopy is used to investigate nanoscale ferroelectric domain engineering in near-stoichiometric lithium niobate (SLN) single crystals. The topography of the SLN single crystal was studied after polished to about 10 micron thickness. Dot patterns of the domain structure were fabricated by applying positive DC voltages of magnitude form 80 to 100 V with different pulse width from 0.5 to 20 s. The dot nanodomains of radius down to 200 nm were fabricated. With the increase of the magnitude of voltage and pulse width, feature size of switched domains increased to 940 nm.

The novel ligand 4′-diferrocenylalkyne-2,2′:6′,2′′-terpyridine (7; Fc-C≡C-Fc-tpy; tpy = terpyridyl; Fc = ferrocenyl) and its Ru2+ complexes 8–10 have been synthesized and characterized by single-crystal X-ray diffraction, cyclic voltammetry, and UV–vis and luminescence spectroscopy. Electrochemical data and UV absorption and emission spectra indicate that the insertion of an ethynyl group causes delocalization of electrons in the extended π* orbitals. Cyclic voltammetric measurements of 7 show two successive reversible one-electron-oxidation processes with half-wave potentials of 0.53 and 0.78 V. The small variations of the E1/2 values for the Fe2+/Fe3+ redox couples after the coordination of the Ru2+ ion suggest a weak interaction between the Ru2+ and Fe2+ centers. After insertion of an ethynyl group, UV–vis absorption spectra show a red shift of the absorption peak of the 1[(d(π)Fe)6] → 1[(d(π)Fe)5(π*tpyRu)1] MMLCT of the Ru2+ complexes. The Ru2+ complex 8 exhibits the strongest luminescence intensity (...

An unusual heteroannular cyclization of methyl 4-(((1′-(trimethylsilyl)ethynyl)ferrocenyl)ethynyl)benzoate (11) under the basic desilylation condition yielded 1,1′-(l-methoxy-3-(4′-(methoxycarbonyl)phenyl)-1,3-butadienylene)ferrocene (7), the first reported 1,3-disubstituted 1,3-butadienyl heteroannular bridged [4]ferrocenophane. Compound 7 has been characterized by elemental analysis, IR spectra, 1H NMR spectroscopy and X-ray diffraction analysis. The electrochemical behavior has been investigated by cyclic voltammetry. The DFT calculation results of 7 are also reported.

Reaction of a new type of bidentate ligand PhPQu [PhPQu = 2-diphenylphosphino-4-methylquinoline] with Fe(CO)5 in butanol gave trans-Fe(FpPQu-P)(CO)3 (1). Compound 1, which can act as a neutral tridentate organometallic ligand, was reacted with I B, II B metal compounds and a rhodium complex to give six binuclear complexes with FeM bonds, Fe(CO)3 (μ-Ph2PQu)MXn (2–7) [M= Zn(II), Cd(II), Hg(II), Cu(I), Ag(I), Rh(I)], and an ion-pair complex [Fe(CO)3 (μ-Ph2PQu)2HgI][HgI3]− (8). The structure of 8 was determined by X-ray crystallography. Complex 8 crystallizes in the space group P-1 with a = 1.0758(3), b = 1.6210(4), c=1.7155(4)nm; a=75.60(2), β=71.81(2), γ=81.78(2)° and Z = 2 and its structure was refined to give agreement factors of R=0.050 and Rw = 0.057. The Fe-Hg bond distance is 0.2536nm.

Dinuclear silver (I) six-membered ring complex [Ag2 (bta)2 -(hmbta)2] (ClO4)2 (3) has been synthesized by the reaction of benzotriazole (bta) (1) and 1-hydroxymethyl benzotriazole (hmbta) (2) with Ag (CH3CN)4ClO4. The structures of compound 2 and Complex 3 have been studied by single crystal X-ray diffraction analysis. The change of luminescent intensity of 1, 2 and 3 was reported. Compound 2 crystallizes in the monoclinic system with space group P2 (1)/c, a = 0.7655 (10) nm, b = 1.0126 (14) nm, c =0.9502 (13) nm, β = 95.07 (2)°, V = 0.7337 (17) nm3 and Z = 4. Complex 3 crystallizes in the triclinic system with space group P1, a = 0.73611 (18) nm, b = 0.9152 (2) nm, c = 1.2277 (3) nm, β = 87.170 (5)°, V = 0.8221 (3) nm3 and Z = 1. The main structural feature of complex 3 is a symmetric dinuclear six-membered ring formed by two silver (I) atoms and four N-atoms from two benzotriazoles. The second structural feature of complex 3 is the τ-τ stacking interaction between two adjacent molecular planes, which forms the two-dimentional layer structure. Besides, compared with 2, the luminescent intensity of complex 3 shows a remarkable enhancement.

Three novel 25,27-dihydroxy-26,28-bis(3-benzylselenopropoxy)-5,11,17,23-tetra-tert-butylcdix[4]-arene (2), 25,27-dihydroxy-26,28-bis[3-(2-hydroxyethylseleno)propoxy]-5,11,17,23-tetra-tert-butyl-calix[4]arene (3) and 25,27-dihydroxy-26,28-bis(3-propylselenopropoxy)-5,11,17,23-tetra-tert-butyI-calix[4]arene (4) were synthesized for the comparison of their ion-selectivity in ion-selective electrodes (ISE). X-ray structure of the CH/π complex of 4·CH2Cl2 was elucidated. ISEs based on 2-4 as neutral ionophores were prepared, and their selectivity coefficients for Ag+ (log K) were investigated against some main group metal ions and transition metal ones using the fixed interference method (FZM). These ISEs showed excellent Ag' selectivity over most of the interfering cations examined. It is evident that the stronger Hg2+ interference may not be produced while hard donors (hydroxy) are close to the soft selenium donors.

Binuclear complexes [M2(μ-BPNNNa)] [ BF 4 - ]2 (M = CuI, 1; M = AgI, 2) were prepared by reaction of 1,5-bis [{6-(diphenylphosphanyl)-2-pyridylmethyl}n-propylamino methyl]naphthalene (BPNNNa) with M(CH3CN)4 BF4 in CH2Cl2 and were structurally characterized by single crystal X-ray diffraction studies. In complexes 1and 2, BPNNNa acts as a chelating ligand and two dppy (2-(diphenylphosphino) pyridine) units with two metal atoms are linked together in head-to-tail mode to form an eight-membered ring, which exhibits an eclipsed conformation. A significant feature in complexes 1 and 2 is the deformation of the flat naphthalene unit, in which the two aryl moieties make an angle of 10.3° (1) and 7.2° (2), respectively. A weak Ag⋯Ag interaction is present in the complex 2.

Novel macrocyclic monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a–5a were synthesized by the reaction of calix[4]arene dibromides 1–5 with the disodium salt of bis(2-selenylethyl)ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X-Ray structure analysis of 1a further confirmed the cone conformation of compounds 1a–5a. An interesting host-guest complex of 1a with dichloromethane via CH/π and Cl/π interactions was elucidated. Extraction experiments showed that these novel monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a–5a had strong extraction ability towards mercury ion. The interaction of Hg2+with the calix ligand has also been investigated by 1H NMR titration.

The ligands bis(imidazolium) hexafluorophosphate [RHimy-(CH2OCH2)n-HimyR][PF6]2 [Himy = –C3N2H3–, imidazolium; R = 1-naphthylmethyl, n = 2 (1a), 3 (2a); R = 9-anthracenylmethyl, n = 2 (1b), 3 (2b)] with a highly flexible polyether chain were easily prepared by the reaction of substituted imidazole with the corresponding polyglycol diiodide, followed by exchange of the anions with PF6–. Ligands 1a,b and 2a,b react with Ag2O to give monometallic AgI-containing N-heterocyclic carbene (NHC) metallacrown ethers 3a,b and 4a,b with a long and highly flexible bridging chain (CH2OCH2)n (n = 2, 3) between the two imidazolium units. Complexes 3a,b and 4a,b react with [Au(SMe2)Cl] in a transmetalation reaction to give AuI analogues 5a,b and 6a,b. Complexes 3a,b–6a,b are novel examples of a metallacrown ether with NHCs. In contrast to the use of a high-dilution technique in the preparation of polyether chain phosphane-containing metallacrown ethers, the new trans-metallacrown ethers can be prepared in concentrated solution. The structures of 3a–6a were confirmed by X-ray diffraction determination. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

The ligands bis-(imidazolium) hexafluorophosphate [ RHimy CH 2 OCH 2 HimyR ] [ PF 6 - ] 2 (Himy = –C3N2H3–, imidazolium; R = 1-naphthylmethylene, 1a; 9-anthracenylmethylene, 1b) with an oxoether chain were easily prepared by the reaction of substituted imidazole with the diglycol diiodide, followed by exchange of anions with PF 6 - . 1a and 1b reacted with Ag2O in DMSO or CH3CN to yield [2 + 2] dinuclear Ag(I) NHCs macrocyclic complexes 2a and 2b, which showed much different conformation in solid corresponding to the R- substituent. Carbene transmetalation reactions of 2a–b with Au(SMe2)Cl give dinuclear Au(I) analogs 3a and 3b. The new NHCs complexes were characterized by elemental analyses, 1H NMR, 13C NMR and the structures of 2a–b and 3a were confirmed by X-ray diffraction determination.

Dinuclear complexes [M2(μ-BPNNAn)]X2 (M = CuI, X = ClO4–1, X = BF4–2; M = AgI, X = BF4–3, X = ClO4–4) have been prepared by treating 9,10-bis{[6-(diphenylphosphanyl)-2-pyridylmethyl]propylaminomethyl}anthracene (BPNNAn) with M(CH3CN)4X in CH2Cl2. The structures of complexes 1, 2 and 3 have been determined by single-crystal X-ray diffraction studies. In the complexes, BPNNAn acts as a chelating ligand and two metal ions riding on two bridgehead carbon atoms in the anthracene group leads to the deformation of the anthracenyl ring. The Cu–Arene charge transfer interaction is observed from the nonfluorescent emission of Cu complex 1, while the Ag complex 3 exhibits dual emission at high concentrations in a CH2Cl2 solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

A novel long chain diphosphine ligand with a pyridine-diamino bridge, 2,6-bis(N-benzyl-N-diphenylphosphinomethylamino)pyridine (PNP1), was prepared conveniently using the Mannich reaction of HPPh2 with paraformaldehyde and 2,6-bis(N-benzylamino)pyridine in high yield. Reactions of the ligand with metal complexes, M(COD)Cl2 (M = Pd, Pt), M(CH3CN)4ClO4 (M = Cu, Ag) and M(CO)6 (M = Mo, W) afforded the corresponding 10-numbered monometallic macrocyclic complexes with an uncoordinated pyridyl bridge. The monometallic chelate PdCl2(PNP1) continued to react with Ag+ or Cu+ giving the μ-Cl bridged bicyclic metallic complex (μ-Cl)2[PdCl(PNP1)]2. The diphenylphosphine group coordinated with metal ion in cis-form in all the 10-numbered macrocyclic metal complexes. Ligand PNP1 and another known analogous 2,6-bis(N-diphenylphosphinoamino)pyridine (PNP2) reacted with Au(SMe2)Cl giving the corresponding bimetallic Au2Cl2(PNP1) and Au2Cl2(PNP2), respectively. The latter bimetallic complexes continued to react with Ag+ and diphosphine ligand to give the corresponding bimetallic macrocyclic complexes Au2(ligand)2(ClO4)2. All the complexes were characterized and the structures of some complexes were confirmed by X-ray single crystallography determination.

1-(9-Anthracenylmethyl)-3-octylimidazolium chloride (1a) or 1-(9-anthracenylmethyl)-3-ethylimidazolium iodide (1b) was treated with (cod)Pt(CCPh)2 to afford the luminescent complexes [1-(9-anthracylmethyl)-3-alkylimidazol-2-ylidene]2Pt(CCPh)2 (2a: alkylC8H17, 2b: alkylC2H5). Complex 2a crystallizes in triclinic system, space group Pi, a=8.615(3), b=13.839(5), c=13.870(5) A, α=85.275(6)°, β=84.062(6)°, γ=72.901(6)°, Z=1. The photophysical properties of 2 were determined.

In the presence of NaH and KOBut, 1-(9-anthracenylmethyl)-3-octylimidazolium chloride (1a) or 1-(9-anthracenylmethyl)-3-ethylimidazolium iodide (1b) was treated with Ni(OAc)2, Pd(OAc)2, or Pt(cod)Cl2 in CH3CN/THF solution to afford the fluorescent complexes [1-(9-anthracenylmethyl)-3-alkylimidazol-2-ylidene]2M(CN)2 (2a, alkyl = C8H17, M = Ni; 2b, alkyl = C2H5, M = Ni; 3a, alkyl = C8H17, M = Pd; 3b, alkyl = C2H5, M = Pd; 4a, alkyl = C8H17, M = Pt; 4b, alkyl = C2H5, M = Pt). The metal(II) center has a square-planar geometry, and pairs of 1-(9-anthracenylmethyl)-3-alkylimidazol-2-ylidene and CN- ligands are in a trans configuration. The CN- ligand in 2−4 derives from C−C bond cleavage in the CH3CN solvent. The fluorescent emission spectra of 1−4 are determined.

In the presence of KOBut, 1-(9-anthracenylmethyl)-3-ethylimidazolium iodide (1) is treated with PdCl2 and Pt(cod)Cl2 in acetonitrile and THF to afford the luminescent complexes [1-(9-anthracylmethyl)-3-ethylimidazol-2-ylidene]2PdCl2 (2) and [1-(9-anthracylmethyl)-3-ethylimidazol-2-ylidene]2PtCl2 (3), respectively, and an analogous treatment with iodine affords [1-(9-anthracylmethyl)-3-ethylimidazol-2-ylidene I]+ I3 − (4). In a refluxed CH2Cl2 solution imidazolium salt 1 is transformed into another salt 1-(9-anthracylmethyl)-3-ethylimidazol-2-ylidene chloride (5). The luminescent emission spectra of 1, 2, 3 and 4 are determined.

Reaction of a new large-bite P,N-ligand, 2-(N-diphenylphosphinomethyl-N-benzyl)aminopyridine (1) with (COD)PtCl2 and (COD)Pt(CCPh)2 give cis-(L)2PtCl2 (2) and trans-(L)2Pt(CCPh)2 (3), respectively. Complex 3 reacted with M(I) (M = Cu, Ag) perchlorate using its pyridyl and alkynyl groups to afford a novel type of mixed-metal macrocyclic complexes PtM2(L)2(CCPh)2(ClO4)2 (M = Cu, 4; M = Ag, 5). Complex 4 can be converted to the solvated complexes Pt[Cu(solvent)]2(μ-L)2(CCPh)2(ClO4)2 (solvent = H2O, 4; CH3CN, 4″) by recrystallization of 4 in the corresponding solvents. The crystal structures of complexes 2, 3, 4 and 4″·CH2Cl2 and luminescence properties of 3, 4 and 5 have been determined.

Based on a novel cocoating strategy and dissociation enhancement lanthanide fluorescence immunoassay technique, a sensitive time-resolved fluoroimmunoassay (TRFIA) has been developed for simultaneous quantification of human serum thyroid-stimulating hormone (TSH) and thyroxin (T4) in a one-and-the-same assay procedure. The new cocoating strategy for preparing highly active surface anti-TSH and anti-T4 monoclonal antibodies (McAbs) was performed by a three-step protocol. Namely, anti-TSH McAb at high concentration (10 micro g/ml) and extensively biotinylated bovine serum albumin (BSA) at low concentration (0.5 micro g/ml) were coated on microwells by passive adsorption, then streptavidin was captured by the surface BSA-biotin, and finally biotinylated anti-T4 McAb was immobilized by the remnant binding sites of the bound streptavidin. In the present TSH/T4 TRFIA, both sandwich- and competitive-type configurations were involved, and Eu(3+) and Sm(3+) were used as labels for TSH and T4 detection, respectively. The method showed rapid kinetics; the equilibrium was reached within 30min at 37 degrees C due to the use of high concentrations of reaction reagents, rapid agitation, and small reaction volume. The lower limits of detection of the method were 0.028 mIU/L for TSH and 4.1 nmol/L for T4 with 20 micro L of sample volume. The assay ranges for TSH and T4 were 0.21-80.00 mIU/L and 20-300 nmol/L, respectively. The correlation between the TSH/T4 values obtained by the present TSH/T4 TRFIA and those obtained by commercial chemiluminescence immunoassay was satisfactory.

Two N(n-Pr)PPh2 groups appended to the 9,10-anthracene positions through methylene spacers as a bidentate ligand coordinate with Cu+, Ag+, and Au+ ions efficiently to afford endocyclic metal complexes with metal-η6-arene bonding, rarely observed for the group 11 metal ions. The three-center metal−NP and metal−η6-arene bonding patterns in the endocyclic complexes were confirmed using ab initio and density functional calculations. The close metal−anthracene centroid distances significantly affected absorption and fluorescence properties of the complexes in solution. Among them the Cu+ complex has the shortest metal−anthracene distance and most drastic spectral abnormality. The close distances also controlled the endocyclic-exocyclic metal transition of the complexes, wherein the equilibrium heavily favored the former on account of η6 interactions. These complexes reacted with phosphines in solution to give highly fluorescent species that were proposed to possess the exocyclic configuration with the three-co...

1-(9-Anthracenylmethyl)-3-ethylimidazolium iodide was heated in CH2Cl2 solution with silver oxide to afford a stair polymer of N-heterocyclic carbene silver(I), which gave strong anthracene-type fluorescence. The carbene moiety could be displaced from this polymer by pyridine to afford a known polymer with a similar shape but a tighter framework; this polymer showed an emission band at 579 nm arising from a Ag−Ag interaction.

A new highly fluorescent beta-diketone-europium chelate was synthesized and employed as a tracer to develop a time-resolved fluoroimmunoassay (TRFIA) for detection of serum total thyroxine (T4). The tetradentate beta-diketone chelator, 1,10-bis(thiophene-2'-yl)-4,4,5,5,6,6,7,7-octafluorodecane-1,3,8,10-tetraone (BTOT), was structurally composed of two units of thenoyltrifluoroacetone (TTA) derivatives but expressed fluorescence that was greatly enhanced, as compared to the original TTA molecules, in the presence of excess amount of Eu3+. The luminescence properties of the europium chelate of BTOT werestudied in aqueous solution. Chlorosulfonylation of BTOT afforded 1, 10-bis(5'-chlorosulfo-thiophene-2'-yl)-4,4,5,5,6,6,7,7-octafluorodecane-1,3,8,10-tetraone (BCTOT), which could be coupled to proteins (i.e., streptavidin or the BSA-T4 conjugate) and used as a tracer for TRFIA. Although the BCTOT-Eu complex could be detected at a very low level (approximately 1.07 x 10(-12) mol/L) in buffered aqueous solution (50 mmoVLTris-HCl; pH, 8.0), the application of the chelate label in direct serum T4 TRFIA experienced a problem of matrix interference, which was probably caused by some unknown chelating components in the samples as a result of the fact that the fluorescence of the BCTOT-Eu chelate was prone to quenching or enhancement by some chelating reagents. To remove this problem, an indirect serum T4 TRFIA was proposed with the use of BCTOT-Eu-labeled streptavidin (SA) as signal generation reagent. The concentrations of T4 in 27 human serums were determined by indirect T4 TRFIA, and the assay results correlated well with those obtained by commercial Coming-CLIA (r = 0.955) and Wallac-DELFIA (r 0.965).

A series of benzothiazolylthiaalkoxy functionalized calix[4]arenes with different tether length between the benzothiazolyl and calix[4]aryl groups have been synthesized and characterized for comparison between the coordinate adjustment behaviors of the two benzothiazolyl groups in the generation of ion-selective electrodes (ISEs). ISEs based on these calix[4]arenes showed excellent Ag+ selectivities, log KAg,Mpot≤−4.0, against most of the interfering cations examined, except for Hg2+ having a very weak interference (log KAg,Mpot≤−2.5). Their plausible recognition mechanism as well as their structure–selectivity relationships are also discussed.

DBPs formation potential, including THMs, HAAs, HKs, chloropicrin, and chloral hydrate, of 20 amino acids was evaluated. Chlorination experiments were carried out at pH=8.0±0.1 by using phosphates buffer and performed at Cl2:N=8:1(molar ratio) at 20±1° C for a reaction duration of 24h. Chlorination experiments shown the DBPs formation potential of 20 amino acids differed considerably and without any obvious relationship to TOC contents. THMs, HAAs, HANs, HKs, chloropicrin, and chloral hydrate formation potential were in the range of 0.001~0.467 mol/mol, 0~0.669 mol/mol, 0.005~1.170 mmol/mol, 0.031~9.270 mmol/mol, 0~1.380 mmol/mol, and 0.059~39.080 mmol/L, respectively. THMs and HAAs were two largest classes of DBPs formed which accounts for 61~99% of total DBPs detected in the experiments except for Glu(43%) and Ile(32%). However, unlike NOM and resorcinol, THMs and HAAs formation were not related which indicated that the THMs and HAAs formation paths were different as compared with NOM. Certain amount of N-DBPs were found, but the formation potential are relatively small when compared with THMs and HAAs.

In our development of total serum thyroxin TRFIA using an immobilized second-antibody (S-Ab) as the separation agent, we observed a significant measurement bias caused by a matrix interference when the immobilized S-Ab had a relatively low binding capacity for the primary anti-T4 monoclonal antibody (McAb). Therefore, we employed a new separation system based on the highly active surface streptavidin and biotinylated anti-T4 McAb. Our results indicate that the matrix interference was removed and the assay performance was improved with the use of streptavidin-biotin separation technique. In our method, microwells were first coated with biotinylated BSA and then a streptavidin solution in the presence of 1% BSA was added to allow streptavidin to be immobilized via the pre-coated BSA-biotin. Surface streptavidin prepared in this protocol expressed a significantly increased binding capacity for the biotinylated anti-T4 McAb, compared to the passively adsorbed S-Ab for binding the original anti-T4 McAb. The immunoreactions between the biotinylated anti-T4 McAb and the T4 in the standard or sample or the europium-labeled T4-BSA conjugate mainly occurred in liquid solution, and then the immune complex was specifically trapped by the surface streptavidin and isolated from the free trace by washing. Serum TT4 TRFIA based on surface streptavidin was accurate, precise and economic, maintained all the merits of the directly immobilized surface antibodies.

Reaction of a carbene precursor containing an anthracene fluorophore and two N-picolyl moieties with Hg(OAc)2 produces the title complex. X-ray studies and UV−vis and fluorescence spectroscopy confirm that a strong interaction exists between the mercury atom and anthracene.

Reaction of the carbene precursor 1 and Ag2O yields the Ag(I) metal crown ether 2a. Carbene transmetalation reaction of 2a with CuI gives Cu(I) analogue 2b. The structures of 2a and 2b are determined by X-ray crystallography.

Three novel mixed heterocalixarenes containing imidazolium units and a heterocalixarene containing two thiourea functionalities have been synthesized. The molecular structures and anion recognition ability of some of these compounds have been ­determined.

The synthesis and crystal structures of binuclear silver(I) and mercury(II) metallocyclophanes with N-heterocyclic carbene linkages by the π−π stacking interaction are described.

Chlorine is the most commonly used chemical for water and wastewater disinfection worldwide, and it reacts with both ammonia and dissolved organic nitrogen. Using the salicylate spectrophotometric method, effects of glycine on the classic breakpoint chlorination are studied using glycine as a surrogate for dissolved organic nitrogen. The results show that the shape of the breakpoint chlorination curve with glycine was analogous to that of water without glycine. Increasing the glycine concentration moves the chlorination breakpoint curve to the right, demonstrating that more chlorine must be added to replace the chlorine consumed by glycine and yield the desired residual active chlorine concentration. At the peak of the chlorination breakpoint curve, both NH2Cl and mono-chlorinated organic chloramine reach their maximum. The Cl2/N ratio of the peak is linearly related to the glycine concentration, and our calculations indicate that the maximum of mono-chlorinated organic chloramine formation by glycine chlorination occurs at a stoichiometric ratio of 1:1; the same as that for chlorinating ammonia to NH2Cl. The distribution of NH2Cl and organic chloramines is controlled by [Gly]/[NH3-N]. At the breakpoint, ammonia and glycine are completely oxidized by chlorine, which leads to chlorine depletion. The stoichiometric ratio for the complete oxidation of glycine was 3:1, larger than that for complete oxidation of ammonia (2:1). For the different stoichiometric ratio in reaction of oxidation of ammonia and glycine, the sum of ammonia and glycine cannot be used as a chlorine dosage control parameter. The chlorine control method involving ammonia and glycine for chlorine and chloramination process is established.

The title compound, C34H33N4, is a new 3,5-di­methyl­pyrazole-substituted para­cyclo­naphthane. Each of the two symmetry-independent mol­ecules in the asymmetric unit occupies a special position on a twofold axis and exhibits an intramol­ecular π–π stacking interaction between the naphthalene moieties. The geometry of both mol­ecules is essentially the same, the bridged rings of the naphthalene nuclei being deformed into a boat shape.

A new high-yielding synthetic approach for the preparation of bimetallic cyclophane has been achieved through the π−π stacking interaction approach from the flexible ligand 1 and group 11 metal M+....

A series of water dispersible polyurethanes containing quaternary ammonium group as the hydrophilic group with different content of trimethylolpropane (TMP) as inner crosslinker were prepared. IR spectroscopy was adopted to demonstrate the polymerization reaction and structure of polymer. The effects of TMP content on PU properties were investigated. Particle size distribution (PSD) analysis and morphology of PU observed by TEM showed that particle size of PU dispersions initially decreased and then increased with increasing TMP content. The viscosity of the PU dispersions with TMP addition was bigger than the PU dispersions without TMP. TG analysis indicated thermal stability and microphase separation degree of PU was enhanced with increasing TMP content. Contact angle and gel content of PU also increased as increasing TMP content. Meanwhile, tensile strength increased and then decreased with the increment of TMP content.

The reaction of 9,10-bis(2-(diphenylphosphino)ethyl)anthracene with [Rh(CO)2Cl]2 in dichloromethane at −30 °C by metal-directed self-assembly affords the novel calix-shaped metallocyclophane [Rh{9,10-bis(2-(diphenylphosphino)ethyl)anthracene}(CO)Cl]3, which adopts a cone conformation and possesses a huge cavity. It has special solution behavior and can encapsulate carbon monoxide in a dichoromethane solution, which leads to fluorescent enhancement emission intensity.

Based on ecological footprint and material flow analysis indicators, a model has been developed to reflect the aggregate environmental pressure and the carrying capacity of a regional economy. The model was applied to calculate the environmental pressure and carrying capacity of Shenyang in the period of 1991–2005. Results show that, of the total ecological footprint of Shenyang, 66%–80% came from carbon footprint and 20%–34% from direct footprint. The carbon footprint increased rapidly after 2000 at an average annual rate of 15.2%, higher than the GDP growth rate (13.76%) in the same period. Therefore, the principal issue of Shenyang's environmental pressure is carbon emission. The direct ecological overload increased steadily at an average annual rate of 6.3%, while the carbon overload increased rapidly after 1998 at an average annual rate of 20.8%, reached 15 million global hectares in 2005. This indicates that there exists a huge gap between the carbon absorption capacity and carbon emission in Shenyang and it is rapidly enlarging.

A new ligand, 2-(N-diphenylphosphinomethyl-N-cyclohexyl)aminopyridine (NNP), was prepared by the Mannich reaction of HPPh2 with 2-(N-cyclohexyl)aminopyridine and paraformaldehyde. The ligand NNP reacted with Fe(CO)5 to give the monometallic complex trans-Fe(CO)3(NNP)2 (2). The reaction of complex 2 with [Cu(CH3CN)4]+[ClO4]- gave a novel complex 3, [(OC)3Fe(μ-NNP)2Cu]+ClO4-, which has two seven-membered macrocycles and an Fe(0) → Cu(I) donor−acceptor bond. The molecular structure of complex 3 was determined by X-ray single-crystal analysis.

The emissive anthraceno−diphosphine 1 reacts with Ag+ ion to afford the nonemissive η6-anthraceno−Ag+ complex 2. Binding of a phosphine molecule to the latter in CH2Cl2 solution by a ligand substitution reaction triggers a strong photoluminescence.

The mercury(II) metal crown ether (2a) was obtained in high yield by reaction of the carbene precursor 1,2-bis[N-(1-naphthylmethylene)imidazoliumethoxy]benzene dihexafluorophosphate (1) and Hg(OAc)2. Addition of NaI to the acetone solution of 2a resulted in precipitation of pale yellow solid 2b. The structures of 2a and 2b were determined by single-crystal X-ray diffractometry. Both molecules display a helical conformation with a torsional cycle. The mercury atom in complex 2a is tricoordinated by two intramolecular carbene carbon atoms and an acetate oxygen atom. The mercury atom in complex 2b is tetracoordinated by two intramolecular carbene carbon atoms and two cis-iodine atoms.