含四硫富瓦烯大环化合物的合成与研究进展

简要介绍了含有四硫富瓦烯(TTF)单元的大环化合物的分类, 概括了各类含四硫富瓦烯大环化合物的合成方法, 主要包括含有1,3-二硫杂环戊烯-2-硫酮单元的大环化合物在亚磷酸三烷基酯参与下的偶合反应, 以及带有氰乙基硫等取代基的预先合成的官能化TTF与二卤代低聚醚的反应. 综述了含四硫富瓦烯大环化合物的电化学性能及其在分子识别方面应用研究的最新进展, 提出了含四硫富瓦烯大环化合物的发展趋势.     

Freeze-fracture electron microscopic and calorimetric studies on microscopic states of surface-modified liposomes with poly(ethylene glycol) chains

The differential scanning calorimetry (DSC) and the freeze-fracture electron microscopy of dipalmitoyl phosphatidylcholine (DPPC) liposomes containing distearoyl-N-monomethoxy poly(ethylene glycol)-succinyl-phosphatidylethanolamines (PEG-DSPE) were carried out. The DSC peak of DPPC liposomes containing PEG-DSPE had a shoulder. The main phase transition temperature of DPPC bilayer membranes containing PEG-DSPE whose molecular weight of PEG is less than 3000 was slightly shifted to a higher temperature, while that containing PEG-DSPE whose molecular weight of PEG is more than 5000 was slightly shifted to a lower temperature. The electron micrographs of freeze-fracture replicas of DPPC liposomes containing PEG-DSPE quenched from 37±2°C exhibited banded and planar textures, suggesting the lateral phase separation in the bilayer membranes.     

Thermal properties of barium complexes used for depositing thin films of YBa2Cu3O7 superconductors

The thermal properties of several barium containing complexes are compared by using thermogravimetric analysis and solids probe mass spectrometry. The properties of complexes containing flourinated and non-fluorinated β-diketonates with and without the presence of a polyether to occupy additional barium coordination sites are compared. Barium complex thermal properties are heavily dependent on the structure of the β-diketones and polyether comprising the complex. Barium complexes containing fluorinated ligands are better suited for chemical vapour deposition of barium than complexes containing non-fluorinated ligands because they efficiently evolve vapours containing barium at lower temperatures.     

Electrical potential oscillation in an anionic surfactant system with barbitone in octanol as an oil phase

Studies were made on oscillations across a liquid membrane consisting of an oil layer, octanol containing barbitone, between two aqueous layers: one containing 8 mM SDS with alcohol and the other containing 0.1 M NaCl. The effects of various concentrations of chemical components in this system on the patterns of electrical oscillation were examined. The oscillations may be explained by the mechanism of repetitive formation and destruction of monolayer structures of the dodecyl sulfate anion at the interface between the organic and the aqueous phases, with the effect of proton penetration. This study of potential oscillation across a membrane containing a drug provides the possibility of further investigations in pharmacological activity.     

Gelatin scaffolds functionalized by silver nanoparticle‐containing calcium alginate beads for wound care applications

The embedding of silver nanoparticle (nAg)‐containing calcium alginate (CaAlg) beads in gelatin scaffolds was aimed to reduce the burst release and prolong the release of silver (Ag⁺) ions for a long period of time. The reduced sizes of the nAg‐containing CaAlg beads were prepared by an emulsification/external gelation method. The diameter of these beads was ~2 µm. The nAg‐containing CaAlg beads were then embedded into gelatin scaffolds by a freeze‐drying method for evaluating the potential of these scaffolds as wound dressings. The compressive modulus of these scaffolds embedded with nAg‐containing CaAlg beads ranged between 7 and 9 kPa. For release study, the cumulative released amounts of Ag⁺ ions from the nAg‐containing CaAlg beads embedded in gelatin scaffolds were lower than those from the nAg‐containing CaAlg beads. Moreover, the nAg‐containing CaAlg beads embedded in gelatin scaffolds had great antibacterial activity and low cytotoxicity. Thus, these scaffolds had potential for sustaining the release and use in wound care applications, especially chronic wound. Copyright © 2016 John Wiley & Sons, Ltd.     

Phenylboronate‐diol crosslinked polymer/SWCNT hybrid gels with reversible sol–gel transition

This work demonstrates the successful incorporation of functionalized single‐walled carbon nanotubes (f‐SWCNTs) into the phenylboronate‐diol crosslinked polymer gel to create a hybrid system with reversible sol–gel transition. The phenylboronic acid‐containing and diol‐containing polymers were first separately prepared by the reversible addition–fragmentation chain transfer polymerization. Covalent functionalization of single‐walled carbon nanotubes (SWCNTs) with an azide‐derivatized, diol‐containing polymer was then accomplished by a nitrene addition reaction. Subsequently, the hybrid gels were prepared by crosslinking the mixture of f‐SWCNTs and diol‐containing polymer with the phenylboronic acid‐containing polymer. The hybrid gel has been characterized by scanning electron microscopy (SEM) and rheological analysis. The SEM measurement demonstrated a homogeneous dispersion of f‐SWCNTs within the gel matrices. Rheological experiments also demonstrated that the hybrid gel exhibited storage moduli significantly higher than those of the native gel obtained from the phenylboronic acid‐containing and diol‐containing polymers. The hybrid gel can be switched into their starting polymer (f‐SWCNTs) solutions by adjusting the pH of the system. Moreover, the hybrid gel revealed a self‐healing property that occurred autonomously without any outside intervention. By employing this dynamic character, it is possible to regenerate the used gel, and thus, it has the potential to perform in a range of dynamic or bioresponsive applications Copyright © 2013 John Wiley & Sons, Ltd.     

Ion pairing between Cl- or ClO4- and alkali metal complexes of ionophore antibiotics in organic solvents: a multinuclear NMR and FT-IR study

The extent of ion pairing in chloride and perchlorate salts was studied by measurement of the Cl- and ClO4- resonances and the observation of the perchlorate stretching frequency by use of nuclear magnetic resonance (NMR) spectroscopy and Fourier transform infrared spectroscopy (FT-IR), respectively, for a variety of ionophores in various solutions and in large unilaminar vesicles (LUVs). The NMR line widths of chloride and perchlorate were larger in solutions containing the neutral ionophores valinomycin (Val) and nonactin (Non) than in solutions containing the negatively charged ionophores nigericin (Nig), lasalocid (Las), and monensin (Mon). The viscosity-corrected perchlorate NMR line widths in solutions containing Val and Las were significantly negatively correlated (r2 > or = 0.99) with the dielectric constant of the solvent. Solvents with low dielectric constants favored ion pair formation. From methanolic solutions containing the Li+, Na+, K+, and Cs+ salts of Cl- and ClO4-, it was determined that the cation with the highest selectivity for the ionophore affords the most ion pairing. A decrease in pH from 7 to 3 had no significant effect on the NMR line widths of chloride and perchlorate in methanolic solutions containing Val, whereas a similar decrease in pH in a methanolic solution containing Mon caused a 2-fold increase in the line widths. The FT-IR difference spectrum of KClO4 in a methanolic solution containing Val showed splitting at the perchlorate stretching frequency. No band splitting was observed in the FT-IR difference spectrum of KClO(4) in methanolic solutions containing Las. The efflux of 35Cl in LUVs containing the neutral ionophore Val followed first-order kinetics with an efflux constant of 1.70 x 10(-3) x min(-1), as determined by 35Cl NMR spectroscopy. The induction of increased membrane permeability in LUVs by the ionophore was determined to be negligible for Val and Nig by fluorescence spectroscopy.     

Photoluminescence spectra of clusters of group IV elements embedded in SiO2 matrices

Using a rf co-sputtering technique, SiO₂ films containing C, Si and Ge atoms were prepared and their Raman and photoluminescence spectra were measured. Raman spectra obtained are very broad indicating that the group IV elements are embedded in the form of clusters. The samples containing C clusters showed a very strong photoluminescence peak at around 2.1～2.2eV (visible with naked eye). The films containing Ge and Si clusters showed luminescence peaks at around 1.6～1.8eV. Strong luminescence was not observed for the samples containing well grown microcrystals a few nanometers in diameter.     

Pyrene-labeled base-discriminating fluorescent DNA probes for homogeneous SNP typing

This paper describes the design of novel base-discriminating fluorescent (BDF) nucleobases and their application to single nucleotide polymorphism (SNP) typing. We devised novel BDF nucleosides, (Py)U and (Py)C, which contain a pyrenecarboxamide chromophore connected by a propargyl linker. The fluorescence spectrum of the duplex containing a (Py)U/A base pair showed a strong emission at 397 nm on 327 nm excitation. In contrast, the fluorescence of duplexes containing (Py)U/N base pairs (N = C, G, or T) was considerably weaker. The proposed structure of the duplex containing a matched (Py)U/A base pair suggests that the high polarity near the pyrenecarboxamide group is responsible for the strong A-selective fluorescence emission. Moreover, the fluorescence of the duplex containing a (Py)U/A base pair was not quenched by a flanking C/G base pair. The fluorescence properties are quite different from previous BDF nucleobases, where fluorescence is quenchable by flanking C/G base pairs. The duplex containing the C derivative, (Py)C, selectively emitted fluorescence when the base opposite (Py)C was G. The drastic change of fluorescence intensity by the nature of the complementary base is extremely useful for SNP typing. (Py)U- and (Py)C-containing oligodeoxynucleotides acted as effective reporter probes for homogeneous SNP typing of DNA samples containing c-Ha-ras and BRCA2 SNP sites.     

Utilization of ion exchangers in analytical chemistry XXVI : Application of the ion-exchange method to solutions containing oxidants

The free acid form of a cation-exchange resin of the sulfonated hydrocarbon type (Dowex 50) can be used for a quantitative liberation of the corresponding acids from salt solutions containing oxidants that are reduced by phenolic resins. Positive results have been obtained with solutions containing bromate, iodate, periodate, molybdate, and chromate. With permanganate a partial reduction occurs which prevents the application of the ion-exchange method for quantitative separation of solutions containing permanganate.     

Low loss second‐order non‐linear optical crosslinked polymers based on a phosphorus‐containing maleimide

A series of crossslinked organic and organic/inorganic polymers based on maleimide chemistry have been investigated for second‐order non‐linear optical (NLO) materials with excellent thermal stability and low optical loss. Two reactive chromophores (maleimide‐containing azobenzene dye and alkoxysilane‐containing azobenzene dye) were incorporated into a phosphorus‐containing maleimide polymer, respectively. The selection of the phosphorus‐containing maleimide polymer as the polymeric matrices provides enhanced solubility and thermal stability, and excellent optical quality. Moreover, a full interpenetrating network (IPN) was formed through simultaneous addition reaction of the phosphorus‐containing maleimide, and sol‐gel process of alkoxysilane dye (ASD). Atomic force microscopy (AFM) results indicate that the inorganic networks are distributed uniformly throughout the polymer matrices on a nano‐scale. The silica particle sizes are well under 100 nm. Using in situ contact poling, the r₃₃ coefficients of 2.2–17.0 pm/V have been obtained for the optically clear phosphorus‐containing NLO materials. Excellent temporal stability (100°C) and low optical loss (0.99–1.71 dB/cm; 830 nm) were also obtained for these phosphorus‐containing materials. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis of oligonucleotides containing Fapy.dG (N(6)-(2-deoxy-alpha,beta-D-erythropentofuranosyl)-2,6-diamino-4-hydroxy-5-formamidopyrimidine) using a 5'-dimethoxytrityl dinucleotide phosphoramidite

Fapy.dG (N(6)()-(2-deoxy-alpha,beta-d-erythropentofuranosyl)-2,6-diamino-4-hydroxy-5-formamidopyrimidine) is a modified purine lesion produced by a variety of DNA-damaging agents, which shows interesting biochemical properties. The previous method for synthesizing oligonucleotides containing Fapy.dG utilized a reverse dinucleotide phosphoramidite, which also required the synthesis of the appropriate reverse phosphoramidites. An improved method for synthesizing oligonucleotides containing Fapy.dG, which does not require reverse phosphoramidites, is described. Fapy.dG containing dinucleotide phosphoramidites containing 5'-thymidine (11a) or 5'-deoxycytidine (15) are prepared and employed in oligonucleotide synthesis. Oligonucleotide purity is assayed using the DNA repair enzyme formamidopyrimidine DNA glycosylase and by ESI-MS.     

Evaluation of the separation characteristics of application-specific (pesticides and dioxins) open-tubular columns for gas chromatography

The solvation parameter model is used to characterize the retention properties of four application-specific open-tubular columns (Rtx-CLPesticides, Rtx-OPPesticides, Rtx-Dioxin and Rtx-Dioxin2) at five equally spaced temperatures over the range 60-140 degrees C. Cluster analysis is used to compare the system constants to a database of forty open-tubular columns characterized according to the same method. System constants differences and retention factor correlation plots are then used to determine selectivity differences between the application-specific columns and their nearest neighbors identified by cluster analysis. The Rtx-CLPesticides and Rtx-OPPesticides columns are shown to belong to the selectivity group containing poly(dimethylmethyltrifluoroprpylsiloxane) stationary phases with Rtx-OPPesticides having a similar selectivity to a poly(dimethylmethyltrifluoropropylsiloxane) stationary phase containing 20% methyltrifluoropropylsiloxane monomer (DB-200) and Rtx-CLPesticides separation properties for a stationary phase containing less than 20% methyltrifluoropropylsiloxane monomer. The Rtx-Dioxin and Rtx-Dioxin2 columns are located in the selectivity group dominated by the poly(dimethyldiphenylsiloxane) stationary phases containing less than 20% diphenylsiloxane monomer. The Rtx-Dioxin and Rtx-Dioxin2 columns are shown to be selectivity equivalent to a (5% phenyl) carborane-siloxane copolymer stationary phase (Stx-500) and a second generation silarylene-siloxane copolymer stationary phase containing dimethylsiloxane and diphenylsiloxane monomers (DB-XLB), respectively.     

Development of analytic microdevices for the detection of phenol using polymer hydrogel particles containing enzyme-QD conjugates

We present the fabrication of a microdevice for the detection of phenol by combining microfluidic channels and poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel microparticles containing tyrosinase-quantum dot conjugates. PHEMA hydrogel microparticles containing conjugates of enzyme (tyrosinase) and quantum dot (QD) were prepared by dispersion photopolymerization and entrapped within a microfilter-incorporated reaction chamber in a microfluidic channel. The fluorescence change, due to the fluorescence quenching effect caused by the enzyme reaction between phenol and tyrosinase, was used to detect phenol. The fluorescence intensity of PHEMA hydrogel microparticles containing tyrosinase-QD conjugates at 585 nm decreased with phenol concentration. In conclusion, the microfluidic channels fabricated in this study entrapping PHEMA hydrogel microparticles containing enzyme-QD conjugates show the potential to be used as an analytic microdevice for the detection of phenol.     

Evaluation of some new 14- and 15-crown-formazans as carriers in cesium ion selective electrodes

A number of new crown-formazans with 14 and 15 membered rings have been investigated as selective neutral carriers in cesium ion selective electrodes. Two plasticizers (NPOE and NPBnE) were studied. The new 14-crown-formazan 4a containing the 4-pyridyl N-oxide at the formazyl carbon exhibited the highest selectivity in cesium ion selective electrodes, especially towards the two low selectivity monovalent ions K⁺ and NH4⁺. Also, membranes containing the plasticizer NPBnE showed better cesium selectivity relative to most ions than those containing NPOE. Membranes containing 4a and variable compositions of plasticizers, potassium tetrakis-(p-chlorophenyl)borate (KTpClPB), and trioctylphosphine oxide (TOPO) were studied in order to prepare an electrode with the optimum cesium selectivity. The highest selectivity for cesium was achieved with the two electrodes designated d and e with membranes containing the ionophore 4a, NPBnE and KTpClPB with and without TOPO. Selectivities are reported relative to sodium, potassium, barium, calcium, ammonium, lithium, cobalt, and magnesium.     

Evaluation of some new 14- and 15-crown-formazans as carriers in cesium ion selective electrodes

A number of new crown-formazans with 14 and 15 membered rings have been investigated as selective neutral carriers in cesium ion selective electrodes. Two plasticizers (NPOE and NPBnE) were studied. The new 14-crown-formazan 4a containing the 4-pyridyl N-oxide at the formazyl carbon exhibited the highest selectivity in cesium ion selective electrodes, especially towards the two low selectivity monovalent ions K(+) and NH4(+). Also, membranes containing the plasticizer NPBnE showed better cesium selectivity relative to most ions than those containing NPOE. Membranes containing 4a and variable compositions of plasticizers, potassium tetrakis-(p-chlorophenyl)borate (KTpClPB), and trioctylphosphine oxide (TOPO) were studied in order to prepare an electrode with the optimum cesium selectivity. The highest selectivity for cesium was achieved with the two electrodes designated d and e with membranes containing the ionophore 4a, NPBnE and KTpClPB with and without TOPO. Selectivities are reported relative to sodium, potassium, barium, calcium, ammonium, lithium, cobalt, and magnesium.     

Synthesis and Characterization of Solid Supports Containing silicon

Combinatorial chemistry has been a new field of chemistry since 1990's.^[1][2] More than 90% of researchers play their emphases on the studies of the solid supports such as P-(CH₂)_n-N and P-(CH₂)_n-O(n=1,2,3), but only a couple researchers play their emphases on the studies of the P-(CH₂)_n-Si(n=1,2,3). Because of the characteristic of the Si-Ar bond, we devise a series of the solid supports containing Si-Ar bond.These solid supports containing silicon were synthesized in two methods. At the same time,we also synthesized the monomer of the solid supports containing silicon or tin. The structures of these compounds were characterized by IR, elemental analysis.The synthetic routes of the solid supports containing silicon are shown in scheme 1 and the synthetic routes of the monomer of the solid supports containing silicon or tin are shown in scheme 2.     

Synthesis of poly-yne polymers containing transition metals,disilane, disiloxane and phosphine groups in the main chain

The synthesis and characterization of metal poly-yne polymers containing disilane, disiloxane and phosphine groups in the main chain are described. The platinum and palladium poly-yne polymers were synthesized by polycondensation reactions between a metal chloride and an α, ω-bisethynyl complex in amines in the presence of cuprous iodide as a catalyst. The nickel poly-yne polymers were synthesized by an alkynyl ligand exchange reaction between a nickel acetylide and an α, ω-bisethynyl complex in diethylamine in the presence of cuprous iodide as a catalyst. The reaction of the platinum poly-yne polymer, containing disiloxane groups in the main chain, with copper (I) salts afforded adducts of η-²-bonded σ-acetylide polymer complexes. The reactions of the palladium poly-yne polymer, containing phosphine groups in the main chain, with transition-metal carbonyl complexes afforded polymer complexes which have phosphorus in the main chain-transition-metal bonds. A concentrated solution of the platinum poly-yne polymer containing disiloxane groups in the main chain forms a lyotropic liquid crystal in dichloromethane or 1, 2-dichloroethane.     

Synthesis and cellular studies of PEG-functionalized meso-tetraphenylporphyrins

The total syntheses of four PEG-functionalized porphyrins, containing one to four low molecular weight PEG chains linked via amide bonds to the para-phenyl positions of meso-tetraphenylporphyrin, are reported. The hydrophobic character of the PEG-porphyrins decreases with the number of PEG chains linked to the porphyrin ring, while their tendency for aggregation in buffered aqueous solution increases. The porphyrins containing one or two PEG chains accumulated within human HEp2 cells to a much higher extent than those having three or four PEGs at the macrocycle periphery. All PEG-porphyrins were found to be non-toxic in the dark, and only those containing one or two PEG chains were phototoxic (IC(50)=2 microM at 1J/cm(2) light dose). The preferential sites of subcellular localization of the porphyrins containing one or two PEG chains were found to be the mitochondria and endoplasmic reticulum (ER), while those containing three or four PEG chains localize preferentially in the lysosomes.     

Kinetics of glycine arenesulfonylation in the water-propan-2-ol system

The kinetics of the glycine N-acylation with 3-nitrobenzenesulfonyl chloride in the water-propan-2-ol mixture containing 40–80 wt% water was studied at 298 K. In going from the mixture containing 40% water to that containing 80% water, the arenesulfonylation rate constant increases by a factor of 40. Glycine is considerably more reactive in the arenesulfonylation than aminobenzoic acids.