几个含噻二唑环芳甲酰基脲的合成及生物活性

通过2-氨基-5-(3-吡啶基)-1,3,4-噻二唑与取代苯甲酰基异氰酸酯反应,得到相应的芳甲酰基脲:N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-氯苯甲酰基)脲(Ⅲa)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-溴苯甲酰基)脲(Ⅲb)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(4-溴苯甲酰基)脲(Ⅲc)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-甲基苯甲酰基)脲(Ⅲd)和N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(4-三氟甲基苯甲酰基)脲(Ⅲe),收率分别为69.5%、67.2%、73.1%、66.8%和71.6%.产物的结构经红外光谱、核磁共振氢谱、质谱与元素分析表征.并对目标化合物进行了植物生长调节活性测试,初步的测试结果表明,目标化合物在10 mg/L表现出一定程度的生长素活性和较好的细胞分裂素活性,其中Ⅲc和Ⅲe的细胞分裂素活性超过40%.     

New fluorinated poly(1,3,4-oxadiazole-ether-imide)s

New fluorinated poly(1,3,4-oxadiazole-ether-imide)s have been prepared by solution polycondensation reaction of different aromatic diamines having preformed 1,3,4-oxadiazole ring, such as 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, 2,5-bis[p-(4-aminophenoxy)phenyl]-1,3,4-oxadiazole, 2,5-bis[p-(3-aminophenoxy)phenyl]-1,3,4-oxadiazole, 2-(4-dimethylaminophenyl)-5-(3,5-diaminophenyl)-1,3,4-oxadiazole and 2-(4-fluorophenyl)-5-(3,5-diaminophenyl)-1,3,4-oxadiazole, with an aromatic dianhydride incorporating ether linkages and hexafluoroisopropylidene group, namely 1,1,1,3,3,3-hexafluoro-2,2-bis-[(3,4-dicarboxyphenoxy)phenyl]-propane dianhydride. The polymers were easily soluble in polar organic solvents, such as N-methylpyrrolidinone, N,N-dimethylformamide, and pyridine, as well as in certain low boiling-point organic solvents, such as tetrahydrofuran and chloroform. Very thin coatings deposited onto silicon wafers exhibited smooth, pinhole-free surface in atomic force microscopy. The polymers showed high thermal stability with decomposition temperature being above 410 °C. They exhibited a glass transition in the temperature range of 183-217 °C, with reasonable interval between glass transition and decomposition temperature. Solutions of some polymers in N,N-dimethylformamide exhibited blue fluorescence, having maximum emission wavelength in the range of 411-424 nm.     

Interface properties of Ti3SiC2/Al2O3 ceramics: Combined experiments and first-principles calculations

The synthesis, characterization, and first-principles calculations of Ti₃SiC₂/Al₂O₃ ceramics were reported. X-ray diffraction measurements showed that the composite ceramics were highly pure. Scanning electron microscopy and transmission electron microscopy were used to characterize the interface information for Ti₃SiC₂ and Al₂O₃ crystals. Surface energies and interface properties were calculated using the first-principles method. The results suggested that Ti₃SiC₂ with Ti terminations and Al₂O₃ with O terminations are more stable than other terminations crystals. Thus powerful attraction between the coordinatively unsaturated Ti and O atoms on the Ti₃SiC₂∥Al₂O₃ interface would result in higher work of adhesion (Wad) and shorter boundary distance, demonstrating the intercrystalline strengthening of Ti₃SiC₂/Al₂O₃ composite ceramics.     

Al2O3 coated glass by aerosol deposition with excellent mechanical properties for mobile electronic displays

Al₂O₃ thin film was deposited on Gorilla glass using an aerosol deposition method to improve the mechanical property of cover glass for mobile electronic device. The deposited Al₂O₃ film (approximately 1 μm thick) was a polycrystalline structure and showed a high light transmittance of approximately 90% in the visible light region. The CIE color space (L*a*b) measurement also showed a characteristic corresponding to the acceptable optical range of the cover glass. Further, it was confirmed that the bending strength improved by 10 %, as compared with bare Gorilla glass (from 6970 kgf/cm² to 7704 kgf/cm²), and the Vickers hardness increased to approximately 1700–2000 HV, as compared with that of Gorilla glass (<700 HV). Owing to the improved mechanical properties, the Al₂O₃ thin film exhibited good anti-scratch properties and is expected to be applied to the cover glass of various display products.     

Comparison of PPAR Ligands as Modulators of Resolution of Inflammation,via Their Influence on Cytokines and Oxylipins Release in Astrocytes

Neuroinflammation is a key process of many neurodegenerative diseases and other brain disturbances, and astrocytes play an essential role in neuroinflammation. Therefore, the regulation of astrocyte responses for inflammatory stimuli, using small molecules, is a potential therapeutic strategy. We investigated the potency of peroxisome proliferator-activated receptor (PPAR) ligands to modulate the stimulating effect of lipopolysaccharide (LPS) in the primary rat astrocytes on (1) polyunsaturated fatty acid (PUFAs) derivative (oxylipins) synthesis; (2) cytokines TNFα and interleukin-10 (IL-10) release; (3) p38, JNK, ERK mitogen-activated protein kinase (MAPKs) phosphorylation. Astrocytes were exposed to LPS alone or in combination with the PPAR ligands: PPARα (fenofibrate, GW6471); PPARβ ({"type":"entrez-nucleotide","attrs":{"text":"GW501516","term_id":"289075981","term_text":"GW501516"}}GW501516, GSK0660); PPARγ (rosiglitazone, GW9662). We detected 28 oxylipins with mass spectrometry (UPLC-MS/MS), classified according to their metabolic pathways: cyclooxygenase (COX), cytochrome P450 monooxygenases (CYP), lipoxygenase (LOX) and PUFAs: arachidonic (AA), docosahexaenoic (DHA), eicosapentaenoic (EPA). All tested PPAR ligands decrease COX-derived oxylipins; both PPARβ ligands possessed the strongest effect. The PPARβ agonist, {"type":"entrez-nucleotide","attrs":{"text":"GW501516","term_id":"289075981","term_text":"GW501516"}}GW501516 is a strong inducer of pro-resolution substances, derivatives of DHA: 4-HDoHE, 11-HDoHE, 17-HDoHE. All tested PPAR ligands decreased the release of the proinflammatory cytokine, TNFα. The PPARβ agonist {"type":"entrez-nucleotide","attrs":{"text":"GW501516","term_id":"289075981","term_text":"GW501516"}}GW501516 and the PPARγ agonist, rosiglitazone induced the IL-10 release of the anti-inflammatory cytokine, IL-10; the cytokine index, (IL-10/TNFα) was more for {"type":"entrez-nucleotide","attrs":{"text":"GW501516","term_id":"289075981","term_text":"GW501516"}}GW501516. The PPARβ ligands, {"type":"entrez-nucleotide","attrs":{"text":"GW501516","term_id":"289075981","term_text":"GW501516"}}GW501516 and GSK0660, are also the strongest inhibitors of LPS-induced phosphorylation of p38, JNK, ERK MAPKs. Overall, our data revealed that the PPARβ ligands are a potential pro-resolution and anti-inflammatory drug for targeting glia-mediated neuroinflammation.     

2-（1，6-二溴-2-萘氧甲基）-5-芳基-1，3，4-噁二唑类化合物的合成与表征

以碳酸钠作缚酸剂，1，6-二溴-2-萘氧乙酰肼（2）与芳酰氯反应制得N，N＇-二酰基肼，后者在voch作用下，脱水环化成2-（1，6-二溴-2-萘氧甲基）-5-芳基-1，3，4-噁二唑类化合物。其结构经元素分析、IR、1^HNMB和MS表征。     

具有"开-关"特性的pH荧光探针DPVF的合成与表征

合成并表征了{4-[2-(4-氟苯基)-乙烯基]-苯基}-二甲基胺(DPVF).结果表明,DPVF(10.0 μmol·L-1)的水∶乙醇=1∶1(体积比)溶液的紫外可见吸收强度对pH值(7.02～2.22)变化灵敏,荧光强度对pH值(7.02～1.66)变化灵敏.荧光增强阶段是氟原子质子化,荧光减弱阶段是氟原子与氮原子同时质子化,氮原子与氟原子都是pH功能基.该化合物显示了"开-关"荧光发射性能,可应用于荧光分子开关;同时又是一个很好的pH荧光探针,检测pH值范围为7.02～1.66,pH值检测最高灵敏度为ΔpH=0.04.     

Syntheses and adsorption properties for Hg2+ of chelating resin of crosslinked polystyrene‐supported 2,5‐dimercapto‐1,3,4‐thiodiazole

A novel chelating resin with functional group containing S and N atoms was prepared using chloromethylated polystyrene and 2,5‐dimercapto‐1,3,4‐thiodiazole (also called bismuththiol I, BMT) as materials. Its structure was characterized by infrared spectra and elementary analysis. The results showed that the content of the functional group was 2.07 mmol BMT g^?1 resin, 47% of which were in the form of monosubstitution (PS‐BMT‐1) and 53% in the form of double substitution (PS‐BMT‐2). The adsorption for mercury ion was investigated. The adsorption dynamics showed that the adsorption was controlled by liquid film diffusion. Increasing the temperature was beneficial to adsorption. The Langmuir model was much better than the Freundlich model to describe the isothermal process. The adsorption activation energy (E_a), ΔG, ΔH, and ΔS values calculated were 18.56 kJ·mol^?1, ‐5.99 kJ·mol^?1, 16.38 kJ·mol^?1, and 37.36, J·mol^?1·K^?1, respectively. The chelating resin could be easily regenerated by 2% thiourea in 0.1 mol·L^?1 HCl with higher effectiveness. Five adsorption–desorption cycles demonstrated that this resin was suitable for repeated use without considerable change in adsorption capacity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1646–1652, 2004     

Optimized pore structure and high permeability of metakaolin/fly-ash-based geopolymer foams from Al– and H2O2–sodium oleate foaming systems

Geopolymer foams have been widely studied as adsorbents owing to their high specific surface areas, high heavy metal immobilization efficiencies, low cost, environmental friendliness, and resource-recycling benefits. In this study, geopolymer foams with different pore structures were prepared from Al– and H₂O₂–sodium oleate foaming systems, and their chemical properties, pore structures, and permeabilities were characterized. The effects of the foaming agent type and surfactant content on the crystal structure and chemical bonding of the materials were analyzed by X-ray diffraction analysis and Fourier-transform infrared spectroscopy, and the pore morphology and structural characteristics were characterized by morphological observations, three-dimensional (3D) reconstruction, and compression tests. Numerical simulations were also carried out to study the structural characteristics of the 3D-reconstructed pores. Furthermore, variations in the permeability coefficient and flow characteristics were tested and analyzed by experiments and simulations. The pores in the geopolymer from the H₂O₂–sodium oleate foaming system tended to be more connected, whereas those in the Al–sodium oleate geopolymers were more complete and closed. The highly connected pore structure facilitates the even diffusion of the solution and effectively increases the amount of adsorption sites. These properties are significant for adjusting the adsorption capacity of geopolymer foams as adsorption monoliths.     

Tuning the electronic and thermal transport behaviors of metal-dispersed Ti2O3 composites derived by metal–insulator transition

Thermal management requires an understanding of the relations among the thermal energy transfer, electronic properties, and structures of thermoconductive materials. Here, we enhanced the metal–insulator transition (MIT)-induced effect on the thermal conductivities of microstructure-controlled Ti₂O₃ composites containing W as a thermal conductive filler at approximately 450 K. To change the electronic and thermal transport properties, we varied the particle radii of the conductive phases in the raw material. The change in the calculated electronic thermal conductivity relative to the electrical conductivity of the W_x(Ti₂O₃)_1?x composite was enhanced by compounding the material. When x was reduced from 50 vol% to 20 vol% and the W particle diameter was reduced from 150 μm to 5 μm, the variation in the estimated electronic thermal conductivity of the W_x(Ti₂O₃)_1?x composite was increased by a factor of 2.01. The total thermal conductivity was also changed by the MIT. At x = 50 vol% and a W particle diameter of 5 μm, the maximum thermal conductivity change was 6.34 times larger than that of pure Ti₂O₃. The detailed relation between the MIT-induced changes in thermal transport and the microstructure were elucidated in classical effective medium approximations.