bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferrocene–β‐Cyclodextrin Conjugates: Synthesis, Supramolecular Behavior, and Use as Electrochemical Sensors
Authors: Casas‐Solvas Juan M. , Ortiz‐Salmerón Emilia , Fernández Ignacio , García‐Fuentes Luís , Santoyo‐González Francisco , Vargas‐Berenguel Antonio
Published: July 2009

Ferrocene with a β‐cyclodextrin unit bound to one or both cyclopentadienyl rings through the secondary face were conveniently synthesized by regiospecific copper(I)‐catalyzed cycloaddition of 2‐O‐propargyl‐β‐cyclodextrin to azidomethyl or bis(azidomethyl)ferrocene. The supramolecular behavior of the synthesized conjugates in both the absence and presence of bile salts (sodium cholate, deoxycholate, and chenodeoxycholate) was studied by using electrochemical methods (cyclic and differential pulse voltammetry), isothermal titration calorimetry, and NMR spectroscopy (PGSE, CPMG, and 2D‐ROESY). These techniques allowed the determination of stability constants, mode of inclusion, and diffusion coefficients for complexes formed with the neutral and, in some cases, the oxidized states of the ferrocenyl conjugates. It was found that the ferrocenyl conjugate with one β‐cyclodextrin unit forms a redox‐controllable head‐to‐head homodimer in aqueous solution. The ferrocene–bis(β‐cyclodextrin) conjugate is present in two distinguishable forms in aqueous solution, each one having a different half‐wave oxidation potential for the oxidation of the ferrocene. By contrast, only one distinguishable form for the oxidized state of the ferrocene–β‐cyclodextrin conjugate is detectable. The redox‐sensing abilities of the synthesized conjugates towards the bile salts were evaluated based on the observed guest‐induced changes in both the half‐wave potential and the current peak intensity of the electroactive moiety.
Perfluorophenyl–Phenyl Interactions in the Crystallization and Topochemical Polymerization of Triacetylene Monomers
Authors: Xu Rui , Schweizer W. Bernd , Frauenrath Holger
Published: July 2009

A series of symmetrically and unsymmetrically substituted octa‐2,4,6‐triyne‐1,8‐diol derivatives with benzoyl, 4‐dodecyloxybenzoyl, as well as perfluorobenzoyl substituents were prepared and investigated with respect to their crystal structures and topochemical polymerizability. Single‐crystal structures for several of these triacetylene monomers have been obtained and proved that the perfluorophenyl–phenyl interactions played a decisive role in the molecular packing. As a consequence of the geometric requirements imposed by the perfluorophenyl–phenyl interactions, packing parameters appropriate for a topochemical triacetylene polymerization in the sense of either a 1,6‐ or a 1,4‐polyaddition along different crystallographic axes were observed in two cases, and UV irradiation led to successful polymerization. Raman as well as solid‐state 13C NMR spectra of the obtained polymers revealed that the polymerization had predominantly proceeded in the form of a 1,4‐polyaddition.
Self‐Assembly in Helical Columnar Mesophases and Luminescence of Chiral 1H‐Pyrazoles
Authors: Beltrán Eduardo , Cavero Emma , Barberá Joaquín , Serrano José Luis , Elduque Anabel , Giménez Raquel
Published: July 2009

Chiral polycatenar 1H‐pyrazoles self‐assemble to form columnar mesophases that are stable at room temperature. X‐ray diffraction and CD studies in the mesophase indicate a supramolecular helical organization consisting of stacked H‐bonded dimers. The liquid‐crystalline compounds reported are 3,5‐bis(dialkoxyphenyl)‐1H‐pyrazoles that incorporate two or four dihydrocitronellyl chiral tails. It can be observed that the grafting of these branched chiral substituents onto the 3,5‐diphenyl‐1H‐pyrazole core has a beneficial role in inducing mesomorphism, because isomeric linear‐chain compounds are not liquid crystalline; this is not the usual scheme of behavior. Furthermore, the molecular chirality is transferred to the columnar mesophase, because preferential helical arrangements are observed. Films of the compounds are luminescent at room temperature and constitute an example of the self‐organization of nondiscoid units into columnar liquid‐crystalline assemblies in which the functional molecular unit transfers its properties to a hierarchically built superstructure.
Structural Analyses of N‐Acetylated 4‐(Dimethylamino)pyridine (DMAP) Salts
Authors: Lutz Volker , Glatthaar Jörg , Würtele Christian , Serafin Michael , Hausmann Heike , Schreiner Peter R.
Published: July 2009

We have studied the formation of several N‐acetyl‐4‐(dimethylamino)pyridine (DMAP) salts (with Cl−, CH3COO−, and CF3COO− counterions), which are considered to be the catalytically active species in DMAP‐catalyzed acetylation reactions of alcohols. Combined crystal structure analyses, variable temperature matrix IR and NMR spectroscopy as well as computational techniques at the UAHF‐PCM‐B3LYP/6‐311+G(d,p)//B3LYP/6‐31G(d) level were utilized to examine the structures and dynamics of salt formation. We found clear evidence for the formation of tight ion pairs that are stabilized by dynamic hydrogen‐bonding interactions. In nonpolar solvents, the nucleophilicity of acetate in its N‐acetyl‐DMAP salt only allows a steady‐state concentration smaller 1 % at room temperature. Thus, we propose additional hydrogen‐bonding interactions with alcohols to be the key stabilization factor in subsequent acetylations.
Low‐tmperature Heat Capacities and Standard Molar Enthalpy of Formation of 4‐Nitrobenzyl Alcohol
Authors: MENG Qingfen , TAN Zhicheng , WANG Xiaohuan , DONG Yaping , LI Wu , SHI Quan
Published: July 2009

Low‐temperature heat capacities of 4‐nitrobenzyl alcohol4‐NBAhave been measured by a high precision automated adiabatic calorimeter over the temperature range from 78 to 396 K. The melting temperature, the molar enthalpy and entropy of the phase transition were determined to be (336.426±0.088) K, (20.97±0.13) kJ·mol−1 and (57.24±0.36) J·K−1·mol−1, respectively. The thermodynamic functions [HT−H298.15 K] and [ST−S298.15 K] were calculated in the range from 80 to 400 K at the interval of 5 K. The constant‐volume energy and standard molar enthalpy of combustion have been determined, ΔcU(C7H7NO3, s) =− (3549.11±1.47) kJ·mol−1 and ΔcHm0 (C7H7NO3, s) =− (3548.49±1.47) kJ·mol−1, by means of a precision oxygen‐bomb combustion calorimeter at T=298.15 K. The standard molar enthalpy of formation has been derived, ΔfHm0 (C7H7NO3, s) =− (206.49±2.52) kJ·mol−1, from the standard molar enthalpy of combustion in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle.
Reduction Kinetics of Thionine in Aerobic Condition with D‐Galactose
Authors: AHMED Khalid , UDDIN Fahim , AZMAT Rafia
Published: July 2009

Reduction kinetics of thionine (Th) with D‐galactose (RH) was observed on a UV/Visible 1601 Shimadzu spectrophotometer at λmax 599 nm. The results showed that the initially slow reduction kinetics got enhanced and proceeded to completion within a few minutes. A pseudo first order kinetics was observed when influence of different parameters like concentration of dye and reductant, ionic strength and temperature was investigated. A significant shift in wave length from 599 to 517 nm was observed at alkaline pH whereas addition of a small amount of acid caused a shift in equilibrium. This resulted in the generation of oxidized form of thionine which was pragmatic in the presence of atmospheric oxygen. Change in ionic strength at elevated temperature lied to decrease in the rate constant. Thermodynamics activation parameters like Ea reflects a high amount of energy required for reduction of Th with RH whereas entropy of activation (ΔS⊖) and free energy of activation (ΔG⊖) show the highly solvated states of transient complex which was less disorderly arranged than the oxidized form of dye. A mechanism consistent with above findings has been discussed in the relevant section of paper.
Photo Decoloration of Methylene Blue with Ribose under Optimum Conditions by Visible Radiation
Authors: AZMAT Rafia , UDDIN Fahim
Published: July 2009

Photo decoloration of the methylene blue (MB) with reducing sugar, ribose (RH), was investigated on an especially designed optical processor using monochromatic radiation of 661 nm through a red filter. The dye molecule gets excited into triplet transient species (MBT) during flushing with lifetime of 10.1 µs into acetate buffered aqueous alcoholic medium, which later on reduces to protonated leuco dye (MBH). Photolysis of the aqueous alcholic medium generated highly reactive oxygen radical (O−·) with the production of 2e−, which led to probable oxidation of the ribose into respective acid while hydrogen abstraction and 2e− reduced the dye (MB) into MBH by following reaction
MBr++RCHO→MBH+RCOOH. Influences of different operational parameters suggest the imperative role of acidity, reductant and temperature where positive relations with quantum yield (π) were established under the optimum conditions while elevated concentration of dye resulted in the decrease in the absorption of number of photon consequently, and no change in the π was observed. A highly solvated transient complex was reported in the reduction of MB and RH through thermodynamics activation parameters. A mechanism of MBT formation and its reduction into MBH has been discussed.
Novel Synthesis of β‐FeOOH Nanofluid and Determination of Its Heat Capacity by an Adiabatic Calorimeter
Authors: NAN Zhaodong , ZHANG Pingping , YU Aijun , WEI Chengzhen , SHI Quan , TAN Zhicheng
Published: July 2009

A novel and facile method for preparation of stable nanofluid is introduced, in which FeCl3·6H2O and urea were used as reactants without any surfactants. The obtained solid sample was proved to be β‐FeOOH by XRD technology and spindle‐shaped by TEM technology. The coexisting NH3 molecules may be the main reason for the stable nanofluid. The weak bonding between nitrogen and iron atoms would be formed. The investigation on the excess heat capacity of the obtained nanofluid sustains this opinion. The heat capacities of the obtained β‐FeOOH particles and the nanofluid were determined by an adiabatic calorimeter. And these obtained results will help the applications of β‐FeOOH and the nanofluid to industry, and the establishment of the model of thermal conductivity of nanofluid. The thermodynamic properties of the obtained β‐FeOOH particles and the nanofluid were calculated based on the obtained functions of heat capacity with respective to thermodynamic temperature and the relationships between the thermodynamic properties.
Preparation and Electrical Property of Ba1.03Ce0.8Ho0.2O3−α Solid Electrolyte
Authors: WANG Maoyuan , QIU Ligan , SUN Yufeng
Published: July 2009

Ba1.03Ce0.8Ho0.2O3−α solid electrolyte with nonstoichiometric composition was prepared by high temperature solid‐state reaction. Phase composition, surface and fracture morphologies of the material were characterized by using XRD and SEM, respectively. Ionic transport number and conductivity of the material were measured by gas concentration cell and ac impedance spectroscopy methods in the temperature range of 600–1000°C in dry air, wet air and wet hydrogen, respectively. Ionic conduction was researched and compared with those of BaCe0.8Ho0.2O3−α and Ba0.97Ce0.8Ho0.2O3−α. The results indicate that Ba1.03Ce0.8Ho0.2O3−α is a single‐phase perovskite‐type orthorhombic system. In the temperature range of 600–1000°C, it is a mixed conductor of oxide ion and electron hole with the oxide ionic transport number of 0.10–0.36 in dry air atmosphere, a mixed conductor of proton, oxide ion and electronic hole with the protonic transport number of 0.11–0.01 and the oxide ionic transport number of 0.34–0.30 in wet air atmosphere, and a pure protonic conductor with the protonic transport number of 1 in wet hydrogen atmosphere. Ba1.03Ce0.8Ho0.2O3−α has the highest conductivities (3.92×10−2 S·cm−1 in dry air, 3.46×10−2 S·cm−1 in wet air, 2.10×10−2 S·cm−1 in wet hydrogen, at 1000°C) among the three materials, and the ionic conduction is superior to that of BaCe0.8Ho0.2O3−α and Ba0.97Ce0.8Ho0.2O3−α under the experimental conditions.
Theoretical Study on Reaction of Furan Anion with N2O in Gas Phase
Authors: LIANG Junxi , GENG Zhiyuan , WANG Yongcheng
Published: July 2009

The mechanism for the ion‐molecule reaction of furan anion with nitrous oxide has been explored theoretically using the QCISD and MP2 levels of theory with the same 6‐31++G(d,p) basis set. As a result, our theoretical investigations strongly suggest that the main pathways, whose energies of all stationary points lie below that of the original reactants (furan anion+N2O), can be expressed as pathways 1 and 2 of the Channel 1, which are two reciprocally competitive pathways. The primary products were C4H3NO−+NO, synchronously, a trace amount of C4H3O2−+N2 should also be monitored in the experiment. Theoretical calculated results are consistent with the experimental observation. Furthermore, the minor pathways were also explained in a nutshell. All the reactive pathways, regardless of the main or minor ones, are strongly exothermic processes.
Synthesis, Characterization and Biological Activity of an Intramolecular Stacking Zinc(II) Complex
Authors: GAO Enjun , LIU Lei , ZHU Mingchang , WU Qiong
Published: July 2009

The synthesis, crystallographic analysis and spectroscopic study of a zinc(II) complex [Zn(bipy)(pmal)(H2O)]· 2H2O (bipy=2,2′‐bipyridine, pmal=phenylmalonic acid) were carried out. The complex has been investigated by the methods of X‐ray crystallography, elemental analysis and IR spectra. The binding ability of the Zn(II) complex to calf thymus (CT‐DNA) was characterized by measuring the effects on the UV spectroscopy and fluorescence spectra of DNA. The agarose gel electrophoresis experimental results suggest that the ligand planarity of complex has a significant effect on cleaving the pBR322 plasmid DNA.
Activation Function of Chloroperoxidase in the Presence of Metal Ions at Elevated Temperature from 25 to 55°C
Authors: GAO Qiang , JIANG Yucheng , GAO Xiaoqin , HU Mancheng , LI Shuni , ZHAI Quanguo
Published: July 2009

The investigation and comparison of chlorination activity of chloroperoxidase (CPO) from Caldariomyces fumago in metal ion solutions to those in pure buffer indicated that CPO could be effectively activated by some alkaline‐earth metals and transition metals. The obtained maximum relative activity of CPO was 1.33 time at 75 µmol·L−1 Ca2+, 1.37 time at 90 µmol·L−1 Mg2+, 1.34 time at 90 µmol·L−1 Ni2+, and 1.27 time at 105 µmol·L−1 Co2+ at 25°C. Moreover, the CPO stability against temperature was improved in the presence of the above metal ions. At 55°C, CPO could retain only about 40% of activity whereas 75% and 81% of activity were maintained in Mg2+ and Ca2+ media, respectively. It was suggested that the metal ions bind to the acid‐base catalytic groups Glu183, His105 and Asp106 around the active site of CPO, and activate CPO by both an enrichment of substrate concentration and the conformational change of CPO, which are favorable to the substrate access. The analysis of kinetic parameters indicated that the activation was mainly due to an increase in kcat values. The affinity and specificity of CPO to substrates were also improved in these metal ion media. The results in this work are promising in view of industrial applications of this versatile biological catalyst.
Synthesis, Structure, Magnetism and Electrochemical Properties of Linear Pentanuclear Complex: Ni5(µ‐dmpzda)4(NCS)2
Authors: YIN Caixia , HUO Fangjun , WANG Wenzhen , ISMAYILOY Rayyat‐H , LEE Genehsiang , YEH Chenyu , PENG Shieming , YANG Pin
Published: July 2009

The synthesis, crystal structure, electrochemical and magnetic properties of a type of pyridine‐modulated linear pentanuclear complex, [Ni5(µ‐dmpzda)4(NCS)2] [dmpzda‐H2=N,N′‐di(4‐methyl pyridin‐2‐yl)pyrazine‐2,6‐diamine], were studied. The complex involves a Ni5 linear chain unit with all of the Ni‐Ni‐Ni being nearly 180°, terminated by the two axial ligands. This pentanuclear linear metal chain is helically wrapped by four syn‐syn‐syn‐syn type dmpzda ligands. There are two types of Ni–Ni distances existing in the complex. The terminal Ni–Ni distances bonded with the axial ligand are longer (2.3821 Å) affected by the axial ligands. The inner Ni–Ni distances are very short and remain constant (2.2959 Å). Two terminal Ni(II) ions bonded with the axial ligands are in a square‐pyramidal (NiN4NCS) environment and exhibit long Ni–N bonds (2.103 Å), which are consistent with a high‐spin Ni(II) configuration. The inner three Ni(II) ions display short Ni–N (1.886–1.906 Å) bond distances, which are consistent with a squareplanar (NiN4), diamagnetic arrangement of a low‐spin Ni(II) configuration. This compound exhibits similar [Ni5(µ‐tpda)4(NCS)2] magnetic behavior, indicating an antiferromagnetic interaction of two terminal high‐spin Ni(II) ions in these complexes.
Synthesis, Characterization and Antimicrobial Activity of Potassium Hydro(benzoyl)(phthalyl)borate and Its Cobalt(II), Nickel(II), and Copper(II) Complexes
Authors: SHARMA Guruaribam Shashikumar , SHEIKH Rayees Ahmad , SHREAZ Sheikh , HASHMI Athar Adil , KHAN Luqman Ahmad
Published: July 2009

A new organoborate ligand, hydro(benzoyl)(phthalyl)borate has been synthesized as its potassium salt (KL) and treatment of KL with one equivalent of MCl2·6H2O gave complexes ML(H2O)x·Cl [x=2, M=Co(II), Ni(II); x=1, M=Cu(II)]. All compounds were characterized by elemental analysis, FTIR, 1H NMR, ESI MS, UV‐Vis techniques, conductivity and magnetic data measurements. Spectroscopic results suggest a square planar geometry in the Cu(II) complex, while the Co(II) and Ni(II) complexes possess an octahedral geometry. Antibacterial activities (in vitro) of the ligand and its metal complexes were studied against two Gram positive (B. subtillis and B. magterium) and two Gram negative bacteria (E. Coli and S. boydi) at a single concentration (75 µg/mL) by using the Disc diffusion method. Antifungal activities (in vitro) were also checked for the compounds by using the same method against Candida albicans 10261, Penicillium sp. and Asperjillius niger., at a single concentration (50 µg/mL). The results showed that all the metal complexes, specially the nickel(II) complex, have higher antibacterial and antifungal activities than the corresponding potassium salt.
Preparation, Characterization and Properties of Ag(I) Coordination Polymer [Ag2(bpp)2(H2O)]·pydc·7H2O
Authors: GUO Chunyan , WEN Guilin , WANG Yaoyu , FU Aiyun , LERMONTOVA Elmira Kh , SHI Qizhen
Published: July 2009

A new coordination polymer, [Ag2(bpp)2(H2O)]·pydc·7H2O (1), derived from the ligand pyridine‐3,5‐dicarboxylic acid (H2pydc), has been obtained through a hydrothermal technique [bpp=1,3‐bis(4‐pyridyl)propane]. Its single crystal structure has been determined by X‐ray crystallography. A 2D sheet containing (H2O)12 water units was formed. Interestingly, each pydc dianion bridged two (H2O)12 units and two free water molecules in the construction of 2D hydrogen‐bonding sheets. Additionally, fluorescent properties, TG analysis, and PXRD for complex 1 were also measured and discussed.
Synthesis, Crystal Structure and Bioactivities of a Novel Propeller Shaped Manganese Complex with the Ligand N′‐Benzylidenesalicylhydrazide
Authors: LI Bo , SUN Xuzhuo , CHENG Gongzhen , JI Zhenping
Published: July 2009

A new propeller shaped mononuclear manganese(III) complex of the general formula: [MnL3(H2O)], where HL is N′‐benzylidenesalicylhydrazide, was synthesized and characterized. The crystal structure of the title compound was characterized by X‐ray single crystal diffractometry, which belongs to a triclinic system with space group P‐1, cell dimensions of a=11.6411 Å, b=12.728 Å, c=16.346 Å, α=110.357°, β=96.555°, γ=108.996°, V=2075.2 Å3, Z=2 and Dcalc=1.265 g/cm3. In this complex, the metal ion is in an octahedral coordination environment, enforcing the stereochemistry of the ligands as a propeller configuration. Antibacterial screening data indicate that the complex has stronger antibacterial activity against the tested microorganisms than the ligand.
Improving the Robustness and Stability of Partial Least Squares Regression for Near‐infrared Spectral Analysis
Authors: SHAO Xueguang , CHEN Da , XU Heng , LIU Zhichao , CAI Wensheng
Published: July 2009

Partial least‐squares (PLS) regression has been presented as a powerful tool for spectral quantitative measurement. However, the improvement of the robustness and stability of PLS models is still needed, because it is difficult to build a stable model when complex samples are analyzed or outliers are contained in the calibration data set. To achieve the purpose, a robust ensemble PLS technique based on probability resampling was proposed, which is named RE‐PLS. In the proposed method, a probability is firstly obtained for each calibration sample from its residual in a robust regression. Then, multiple PLS models are constructed based on probability resampling. At last, the multiple PLS models are used to predict unknown samples by taking the average of the predictions from the multiple models as final prediction result. To validate the effectiveness and universality of the proposed method, it was applied to two different sets of NIR spectra. The results show that RE‐PLS can not only effectively avoid the interference of outliers but also enhance the precision of prediction and the stability of PLS regression. Thus, it may provide a useful tool for multivariate calibration with multiple outliers.
Electrospray Ionization Mass Spectra of Dipeptide Derivatives
Authors: LUO Zaigang , ZENG Chengchu , YANG Daoshan , HUANG Yali , WANG Fang , DU Hongguang , HU Liming
Published: July 2009

Based on the structure of the HIV integrase core domain, dipeptide derivatives, as a type of HIV integrase inhibitor, were synthesized, and their fragmentation pathways were investigated by electrospray ionization mass spectrometry (ESI‐MSn) in conjunction with tandem mass spectrometry (MS/MS). In order to better understand the fragmentation pathways, the MS2 and MS3 spectra of the title compound were obtained. The main fragmentation pathways occur by the cleavage of the C–CO bonds between N‐(benzothiazol‐2‐yl)aminocarbonyl and methylene, NH–CO bonds between the NH groups and carbonyl groups. Electrospray ionization was proven to be a good method for the structural characterization and identification of this kind of compound.
Highly Efficient N‐Monomethylation of Primary Aryl Amines
Authors: PENG Yiyuan , LIU Hanliang , TANG Min , CAI Lisheng , PIKE Victor
Published: July 2009

A highly efficient method for specific synthesis of N‐monomethylarylamines is presented. Anilines were treated with acetic anhydride and triethylamine in dry CH2Cl2 to give the corresponding acetamides. The subsequent N‐monomethylation of acetyl aryl amines with methyl iodide and NaH in THF introduced methyl group. Acid hydrolysis of the N‐methyl acetanilides in ethylene glycol generated the corresponding N‐methyl‐N‐aryl amines in high yields. This method was also used to synthesize (E)‐2‐bromo‐5‐(4‐methylaminostyryl)pyridine that may be useful as an amyloid imaging agent for Alzheimer's disease.
Synthesis and in vitro Study of Novel Methylenebis(phenyl‐ 1,5‐benzothiazepine)s and Methylenebis(benzofuryl‐1,5‐benzothiazepine)s as Antimicrobial Agents
Authors: SANJEEVA REDDY Cherkupally , PURNACHANDRA REDDY Gurrala , NAGARAJ Adki
Published: July 2009

A series of methylenebis(phenyl‐1,5‐benzothiazepine)s 4 and methylenebis(benzofuryl‐1,5‐benzothiazepine)s 5 were prepared by the reaction of methylene‐bis‐chalcones 3 with 2‐aminothiophenol for 4 and followed by the condensation with chloroacetone for 5. The structures of the synthesized compounds have been confirmed by their IR, 1H NMR, 13C NMR, MS and elemental analyses. All the synthesized compounds were tested for their antimicrobial activity against Gram‐positive, Gram‐negative bacteria and fungi. To elucidate the essential structural requirements for the antimicrobial activity, the preliminary structure‐activity relationship has been described. Among the compounds tested, the dimeric compounds 4f, 4g, 5f and 5g were found to be most active against Bacillus subtilis, Bacillus sphaericus, Staphylococcus aureus, Klebsiella aerogenes and Chromobacterium violaceum. Similarly these dimeric compounds showed potent antifungal activity against Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, and Trichophyton mentagrophytes. It is interesting to note that the dimeric compounds with substituents of heterocyclic ring at the 4th position of benzothiazepine system displayed notable antibacterial activity equal to that of streptomycin and penicillin. Further, the activity of all the dimeric compounds was compared with that of their monomeric compounds, and it is interesting to note that almost all the dimeric compounds showed enhanced activity than their monomeric compounds.
Sulfamic Acid as a Green and Reusable Catalyst for the Preparation of β‐Enaminones
Authors: WANG Lei , LU Xiaohua , AN Litao , ZOU Jianping
Published: July 2009

Sulfamic acid can effectively catalyze the reaction of (‐diketones with arylamines to afford the β‐enaminones. The present method offers several advantages, such as high yield, short reaction time, mild conditions, easy work‐up and catalyst recyclability.
Synthesis and Application of Some Azo and Azomethine Dyes Containing Pyrazolone Moiety
Authors: RIZK Hala F. , El‐BORAI Mohamed A. , El‐HEFNAWY Gad B. , El‐SAYED Hatem F.
Published: July 2009

3‐Amino‐1‐phenyl‐4,5‐dihydro‐1H‐pyrazol‐5‐one (1) was used as starting material for the synthesis of a number of azo compounds 3a–3c and azomethine derivative 4. The deblocking of 3a–3c and 4 gave rise to 5a–5c and 6 in which a free amino was revealed. The diazonium salts of 5a–5c and 6 were coupled with several phenols to produce a number of bis azo compounds 7a–7c and 8a–8c with azomethine in position 4 and azoic group in position 3. The prepared dyes were structurally confirmed by elemental analysis, spectral methods and applied to different fibers (wool, polyester and blend of wool/polyester) as disperse dyes and their fastness properties were measured.
Synthesis and Application of Prenyl‐Derived Photoaffinity Probes
Authors: LI Lingdong , TANG Wei , ZHAO Zongbao
Published: July 2009

Three photoaffinity probes containing isoprenoid chains and an azide group were synthesized using one‐pot coupling reaction as the key step. The capability of these probes as labeling agents for isoprenoid chain‐interacting proteins from Saccharomyces cerevisiae proteome was validated by photoaffinity reaction and "click" conjunction with the biotin reporter followed by streptavidin blot analysis.
Synthesis and Biological Activity of 4,5‐Dihydro‐1,2,4‐triazole‐5‐thione Schiff Base
Authors: SUN Xiaohong , BAI Yan , LIU Yuanfa , CHEN Bang , JIA Yingqi , ZENG Zhenfang
Published: July 2009

The 4,5‐dihydro‐1,2,4‐triazole Schiff base derivatives were synthesized with 4‐amino‐4,5‐dihydro‐3‐(phenoxy‐ methyl)‐1H‐1,2,4‐triazole‐5‐thione and substituted benzaldehydes. The chemical structures of the compounds have been confirmed by 1H NMR, IR spectra and elemental analysis. Their biological activities were investigated, and the results showed that they exhibited good fungicidal activities.
Synthesis and Properties of Dimesogenic Compounds Containing Cholesterol and 4‐(trans‐4‐n‐Alkylcyclohexyl)‐benzoic Acid Moieties
Authors: YU Haibo , HOU Ruibin , CHEN Tie , YIN Bingzhu , MUHAMMAD Jamil , JEON Youngjae
Published: July 2009

A series of novel dimesogenic compounds containing cholesterol and 4‐(trans‐4‐n‐alkylcyclohexyl)benzoic acid moieties were synthesized. The two mesogenic units of these compounds are linked with ω‐oxyalkanoyl spacers of varying lengths. The chemical structure and mesomorphic properties of this series of compounds were characterized by FT‐IR, MS, 1H NMR, polarizing optical microscopy (POM) and DSC techniques. The average viscosity and helical twisting power (HTP) in host liquid crystals of selected dimesogenic compounds were also measured. It was found that most of the present novel series of compounds exhibited only cholesteric mesophase with lower phase transition temperatures, and the average viscosity and HTP of selected compounds were similar to or superior to cholesteryl nonylate.
A Novel Liposomal Dexamethasone Palmitate Formulation and Anti‐inflammatory Effects on Mice
Authors: LI Ji , YANG Jing , WANG Wenxin , YU Jichen , FU Jingguo , WANG Xiaolai
Published: July 2009

A novel dexamethasone palmitate liposomal long‐circulating (DPL long‐circulating) drug delivery system was established. The DPL long‐circulating and DPL (dexamethasone palmitate liposomal) systems were prepared by film‐distributed extrusion with phospholipid and cholesterol. The formulation stability of DPL long‐circulating and DPL were investigated. The anti‐inflammatory activity and acute toxicity of DPL long‐circulating, DPL and dexamethasone sodium phosphate injection (DSP) were evaluated with mice. The DPL long‐circulating systems were successfully prepared by film‐distributed extrusion methods. The experimental results showed that the DPL long‐circulating had uniform particle size and stable property. The DPL long‐circulating and DPL showed stronger anti‐inflammatory effect than DSP in an anti‐inflammatory test. Acute toxicity tests showed that DSP injection had lower toxicity than the DPL long‐circulating and DPL, which suggested that DPL long‐circulating and DPL had higher bioavailability with passive targeting efficacy of liposomes. The DPL long‐circulating formulation product can meet quality requirement. This formulation had stronger anti‐inflammatory effect and higher acute toxicity.
An Efficient Solvent‐free Synthetic Technique of 4,4′‐Diaminotriarylmethane Leuco Materials
Authors: JAFARPOUR Farnaz , BARDAJEE Ghasem R. , PIRELAHI Hooshang , OROOJPOUR Vahid , DEHNAMAKI Hamideh , RAHMDEL Sareh
Published: July 2009

An efficient, versatile and solvent‐free synthetic technique of diaminotriarylmethanes was reached by treating N,N‐dimethylaniline with some arylaldehydes over zirconium(IV) oxide chloride (ZrOCl2·8H2O), in which ZrOCl2·8H2O has good activity, easy availability, recovery as well as reusability.
Photoluminescence and Electroluminescence Properties of CdTe Nanoparticles in Conjugated Polymer Hosts
Authors: GUO Fengqi , XIE Puhui
Published: July 2009

The photoinduced energy transfer process from conjugated polymer (PPE4+) to CdTe nanocrystals was found both in solutions and in thin films by a fluorescence spectroscopic technique. Films of PPE4+ blended with CdTe‐2 nanocrystals were formed by an electrostatic layer‐by‐layer assembly technique. Light emitting diodes were fabricated using CdTe‐2 as an emitter in PPE4+ host. PPE4+ works as a molecular wire in the energy transfer process from the polymer to the CdTe‐2 nanocrystals.
Associations between lifestyle factors and quality of life among older long‐term breast, prostate, and colorectal cancer survivors
Authors: Mosher Catherine E. , Sloane Richard , Morey Miriam C. , Snyder Denise Clutter , Cohen Harvey J. , Miller Paige E. , Demark‐Wahnefried Wendy
Published: July 2009

BACKGROUND:

Older cancer survivors are at increased risk for secondary cancers, cardiovascular disease, obesity, and functional decline and, thus, may benefit from health‐related interventions. However, to the authors' knowledge, little is known regarding the health behaviors of older cancer survivors and the associations of those behaviors with quality‐of‐life outcomes, especially during the long‐term post‐treatment period.

METHODS:

In total, 753 older (aged ≥65 years) long‐term survivors (≥5 years postdiagnosis) of breast, prostate, and colorectal cancer completed 2 baseline telephone interviews to assess their eligibility for a diet and exercise intervention trial. The interviews assessed exercise, diet, weight status, and quality of life.

RESULTS:

Older cancer survivors reported a median of 10 minutes of moderate‐to‐vigorous exercise per week, and only 7% had Healthy Eating Index scores >80 (indicative of healthful eating habits relative to national guidelines). Despite their suboptimal health behaviors, survivors reported mental and physical quality of life that exceeded age‐related norms. Greater exercise and better diet quality were associated with better physical quality‐of‐life outcomes (eg, better vitality and physical functioning; P < .05), whereas greater body mass index was associated with reduced physical quality of life (P < .001).

CONCLUSIONS:

The current results indicated a high prevalence of suboptimal health behaviors among older, long‐term survivors of breast, prostate, and colorectal cancer who were interested in lifestyle modification. In addition, the findings pointed to the potential negative impact of obesity and the positive impact of physical activity and a healthy diet on physical quality of life in this population. Cancer 2009. © 2009 American Cancer Society.
Anxiety and distress during active surveillance for early prostate cancer
Authors: van den Bergh Roderick C. N. , Essink‐Bot Marie‐Louise , Roobol Monique J. , Wolters Tineke , Schröder Fritz H. , Bangma Chris H. , Steyerberg Ewout W.
Published: July 2009

BACKGROUND:

Patients on active surveillance (AS) for early prostate cancer (PC) may experience feelings of anxiety and distress while living with “untreated” cancer. In this study, these feelings were quantified, and their associations with various psychologic, medical, demographic, and decision‐related factors were assessed.

METHODS:

Men with recently diagnosed PC who participated in a prospective protocol‐based AS program (the Prostate Cancer Research International: Active Surveillance study [PRAIS]) received a questionnaire (N = 150). Scores concerning decisional conflict (the Decisional Conflict Scale), depression (the Center for Epidemiologic Studies Depression Scale), generic anxiety (the abridged State‐Trait Anxiety Inventory), and PC‐specific anxiety (the Memorial Anxiety Scale for Prostate Cancer) were compared with reference values and the literature. Associations with scores on physical health (the Medical Outcomes Study 12‐item short‐form Physical Component Summary), personality (the Eysenck Personality Questionnaire), shared decision‐making, knowledge of PC, and demographic and medical parameters were determined with univariate and multivariate linear regression analyses.

RESULTS:

The questionnaire response rate was 86% (129 of 150 men). Of all respondents, 81%, 92%, 83%, and 93% scored better than reference values for clinically significant uncertainty regarding the treatment decision, depression, generic anxiety, and PC‐specific anxiety, respectively. Scores were comparable to or more favorable than those of men (reported in literature) who underwent other treatments for localized PC. In multivariate analysis, the following associations emerged: a perceived important role of the physician in shared decision‐making was associated with higher decisional conflict, better physical health was associated with lower depression, neurotic personality was associated with higher depression and with generic and PC‐specific anxiety, and higher prostate‐specific antigen level was associated with higher PC‐specific anxiety.

CONCLUSIONS:

Men on protocol‐based AS mainly reported favorable levels of anxiety and distress. A neurotic personality score was associated with unfavorable effects. These findings may help to optimize patient selection for AS or to select men for supportive measures. Cancer 2009. © 2009 American Cancer Society.
Influence of Intermolecular Vibrations on the Electronic Coupling in Organic Semiconductors: The Case of Anthracene and Perfluoropentacene
Authors: Martinelli Nicolas G. , Olivier Yoann , Athanasopoulos Stavros , Ruiz Delgado Mari‐Carmen , Pigg Kathryn R. , da Silva Filho Demétrio A. , Sánchez‐Carrera Roel S. , Venuti Elisabetta , Della Valle Raffaele G. , Brédas Jean‐Luc , Beljonne David , Cornil Jérôme
Published: July 2009

We have performed classical molecular dynamics simulations and quantum‐chemical calculations on molecular crystals of anthracene and perfluoropentacene. Our goal is to characterize the amplitudes of the room‐temperature molecular displacements and the corresponding thermal fluctuations in electronic transfer integrals, which constitute a key parameter for charge transport in organic semiconductors. Our calculations show that the thermal fluctuations lead to Gaussian‐like distributions of the transfer integrals centered around the values obtained for the equilibrium crystal geometry. The calculated distributions have been plugged into Monte‐Carlo simulations of hopping transport, which show that lattice vibrations impact charge transport properties to various degrees depending on the actual crystal structure.
Ultrafast Structural Dynamics of Biomolecules Examined by Multiple‐Mode 2D IR Spectroscopy: Anharmonically Coupled Motions are in Harmony
Authors: Wang Jianping , Cai Kaicong , Ma Xiaoyan
Published: July 2009

Quantum chemical computations, molecular dynamics simulations, and linear and nonlinear infrared spectral simulations are carried out for four representative biomolecules: cellobiose, alanine tripeptide, L‐α‐glycerylphosphorylethanolamine, and the DNA base monomer guanine. Anharmonic transition frequencies and anharmonicities for the molecules in vacuum are evaluated. Instantaneous normal‐mode analysis is performed and the vibrational frequency distribution correlations are examined for the molecules solvated in TIP3P water. Many local and regional motions of the biomolecules are predicted to be anharmonically coupled and their vibrational frequencies are predicted to be largely correlated. These coupled and correlated vibrational motions can be easily visualized by pairwise cross peaks in the femtosecond broadband two‐dimensional infrared (2D IR) spectra, which are simulated using time‐domain third‐order nonlinear response functions. A network of distinctive spectral profiles of the 2D IR cross peaks, including peak orientations and positive and negative signal patterns, are shown to be intimately connected with the couplings and correlations. The results show that the vibrational couplings and correlations, driven by solvent interactions and also by intrinsic vibrational interactions, are vibrational mode dependent and thus chemical group dependent, and form the structural and dynamical basis of the anharmonic vibrators that are ubiquitous in biomolecules.
Complex joint R&D projects: From empirical evidence to managerial implications
Authors: Arranz N. , Fdez de Arroyabe J. C.
Published: July 2009

At present, the role of joint R&D projects becomes fundamental for understanding the process of innovation. An extensive bibliography exists on the study of the organizations; however, the networks for the development of joint R&D projects themselves as a new form of organization are still a growing field of study. The aim of this article is to provide empirical evidence on joint R&D projects management. To approach this question the starting point will be that joint R&D projects are complex phenomena whose complexity derives from the heterogeneity of agents to take part, the technological process developed and from the organizational form that supports R&D projects. The empirical evidence through European R&D Programs shows the multidimensional character of the joint R&D project concept and allows analyze their different subsystems that is, technological, structural, and governance subsystem. This study not only offers a conceptual framework to help manage these projects, but also discusses practical guidelines that may be useful for its running and management. © 2009 Wiley Periodicals, Inc. Complexity, 2009
Randomness, chaos, and structure
Authors: Atay Fatihcan M. , Jalan Sarika , Jost Jürgen
Published: July 2009

We show how a simple scheme of symbolic dynamics distinguishes a chaotic from a random time series and how it can be used to detect structural relationships in coupled dynamics. This is relevant for the question at which scale in complex dynamics regularities and patterns emerge. © 2009 Wiley Periodicals, Inc. Complexity 2009
Consideration of wheel slip and readhesion control for induction traction motor electric locomotives with individual traction control
Authors: Yasuoka Ikuo , Mochizuki Yasufumi , Toda Shin‐Ichi , Nakazawa Yosuke , Hongguang Gao , Huiyan Liu
Published: July 2009

We have developed a readhesion control algorithm of the traction inverter for individual motor control locomotives. This paper describes improvements in dealing with wheel slip and readhesion control for individual‐axle electric locomotives. The major torque control is based on feedback of the difference between the basic speed of the locomotive and the individual axle speed. By combining two torque control methods, we have obtained better readhesion characteristics: little influence of dynamic axle load transfer and a high achievable coefficient of adhesion exceeding 30%. These torque control characteristics were estimated test runs and the stability limits of feedback gain are shown. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(3): 56–64, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20883
Performance improvement of induction motor speed sensor‐less vector control system using an adaptive observer with an estimated flux feedback in low‐speed range
Authors: Fukumoto Tetsuya , Kato Yousuke , Kurita Kazuya , Hayashi Yoichi
Published: July 2009

Because of various errors caused by the dead time of an inverter, temperature variation of resistances, and so on, speed estimation error is inevitable in speed sensor‐less vector control of an induction motor. In particular, the speed control loop becomes unstable at near‐zero frequencies. In order to solve these problems, this paper proposes a novel design of an adaptive observer for speed estimation. By adding a feedback loop of the error between the estimated flux and the flux command, the sensitivity of speed estimation and primary resistance identification is improved. The proposed system is analyzed and appropriate feedback gains are derived. Experimental results showed good performance in the low‐speed range. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(3): 33–46, 2009; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20909
IL‐7 is essential for lymphopenia‐driven turnover of colitogenic CD4+ memory T cells in chronic colitis
Authors: Tomita Takayuki , Kanai Takanori , Totsuka Teruji , Nemoto Yasuhiro , Okamoto Ryuichi , Tsuchiya Kiichiro , Sakamoto Naoya , Ohteki Toshiaki , Hibi Toshifumi , Watanabe Mamoru
Published: July 2009

We previously demonstrated that IL‐7 is essential for the persistence of T‐cell‐mediated colitis, by showing that adoptive transfer of CD4+CD45RBhigh T cells into IL‐7−/−×RAG‐1−/− mice did not induce colitis; and that intestinal IL‐7 is not essential for this colitis model, by showing that IL‐7−/−×RAG‐1−/− mice parabiosed with colitic CD4+CD45RBhigh T‐cell‐transferred RAG‐1−/− mice developed colitis. Here, we investigated the role of IL‐7 in the maintenance of colitogenic CD4+ T cells by surgically separating these parabionts. Surprisingly, the separated IL‐7−/−×RAG‐1−/− mice were consistently diseased after separation, although no IL‐7 mRNA was detected in the tissues of separated IL‐7−/−×RAG‐1−/− partners. CD4+ T cells isolated from the separated RAG‐1−/− or IL‐7−/−×RAG‐1−/− mice were then transferred into new RAG‐1−/− or IL‐7−/−×RAG‐1−/− mice. Regardless of the source of donor cells, RAG‐1−/− recipients developed colitis, whereas IL‐7−/−×RAG‐1−/− recipients did not. Collectively, these results demonstrate that IL‐7 is essential for lymphopenia‐driven turnover of colitogenic CD4+ T cells rather than the maintenance of those cells in established colitic mice. They also provide a basis for the timing of IL‐7/IL‐7R blockade for the treatment of inflammatory bowel diseases.
L‐Arginine deprivation impairs Leishmania major‐specific T‐cell responses
Authors: Munder Markus , Choi Beak‐San , Rogers Matthew , Kropf Pascale
Published: July 2009

The amino acid L‐arginine plays a crucial role in the regulation of immune responses. We have recently shown that uncontrolled replication of Leishmania parasites at the site of pathology correlates with high levels of arginase activity in nonhealing leishmaniasis and that this elevated arginase activity causes local depletion of L‐arginine. To further our understanding of the impact of L‐arginine deprivation in experimental leishmaniasis, here we characterize in detail the effects of L‐arginine deprivation on antigen‐specific T cells and MΦ. The results of our study show that decrease of L‐arginine levels in the extracellular milieu affects the biological activities of Leishmania major‐specific T cells, both at the level of the magnitude and the quality of their responses. L. major‐specific CD4+ T cells rendered hyporesponsive by L‐arginine deprivation can be partially rescued by addition of exogenous L‐arginine to produce IL‐4 and IL‐10, but not to produce IFN‐γ. Furthermore, our results show that L‐arginine deprivation also greatly impacts parasite growth in activated macrophages. In summary, our results suggest that L‐arginine levels affect both Th cell responses and parasite replication.
Plasmacytoid DC promote priming of autoimmune Th17 cells and EAE
Authors: Isaksson Magnus , Ardesjö Brita , Rönnblom Lars , Kämpe Olle , Lassmann Hans , Eloranta Maija‐Leena , Lobell Anna
Published: July 2009

EAE, an animal model for MS, is a Th17 and Th1‐cell‐mediated autoimmune disease, but the mechanisms leading to priming of encephalitogenic T cells in autoimmune neuroinflammation are poorly understood. To investigate the role of plasmacytoid DC (pDC) in the initiation of autoimmune Th17‐ and Th1‐cell responses and EAE, we depleted pDC with anti‐pDC Ag‐1 (anti‐PDCA1) mAb prior to immunization of C57BL/6 mice with myelin oligodendrocyte glycoprotein (MOG). pDC‐depleted mice developed less severe clinical and histopathological signs of EAE than control mice, which demonstrates a promoting role for pDC in the initiation of EAE. The levels of type I IFN were much lower in the sera from anti‐PDCA1‐treated mice. However, neutralization of type I IFN ameliorated the early phase of EAE but did not alter the severity of disease. Thus, only a minor part of the EAE‐promoting effect of pDC appears to be mediated by IFN‐α/β secretion. The numbers of MOG‐specific Th17 cells, but not Th1 cells, were lower in spleen from anti‐PDCA1‐treated mice compared with controls. In contrast, pDC depletion a week after MOG immunization resulted in more severe clinical signs of EAE. In conclusion, we demonstrate that pDC promote initiation of MOG‐induced Th17‐cell responses and EAE.
IL‐18 skews the invariant NKT‐cell population via autoreactive activation in atopic eczema
Authors: Lind Sara M. , Kuylenstierna Carlotta , Moll Markus , D. Jordö Emilie , Winqvist Ola , Lundeberg Lena , Karlsson Maria A. , T. Linder Maria , Johansson Catharina , Scheynius Annika , Sandberg Johan K. , Karlsson Mikael C. I.
Published: July 2009

Atopic eczema (AE) is a chronic relapsing inflammatory skin disease where the commensal yeast Malassezia can act as a microbial trigger factor. Malassezia activates human DC to produce IL‐18, an innate cytokine that is elevated in serum of AE patients; however, the precise role of IL‐18 in human AE etiology is unknown. Herein, we investigated the effect of IL‐18 on the human invariant NKT (iNKT) cell compartment in AE. We found that IL‐18 was a potent activator of human iNKT‐cells and promoted a pro‐inflammatory CD1d‐dependent response, even in the absence of exogenous ligands. Chronic activation via IL‐18 on the other hand was inhibitory and skewed the iNKT‐cell pool by selectively suppressing CD4+ iNKT‐cells. This was mimicked in AE patients where the proportion of CD4+ iNKT‐cells was reduced in peripheral blood and coincided with elevated plasma levels of IL‐18. Furthermore, a reduced CD4+ iNKT‐cell pool was associated with elevated IgE levels in plasma, and the plasma levels of IL‐18 correlated with both total IgE and disease severity in the AE patients. Based on these findings, we propose that IL‐18‐mediated activation and subsequent dysregulation of the CD1d‐restricted iNKT‐cells plays a role in the pathogenesis of human AE.