bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Properties, and Evolution Mechanism of Morphology Tunable InPO4 Crystals
Authors: Lin Xin‐Hong , Wang Ya‐Chen , Su Yu‐Han , Yang Chung‐Sung
Published: May 2015

In the synthesis of InPO4 crystals, using F127 [(EO)106(PO)70(EO)106] as a structure‐directing template, a morphology tunable progress was observed during the crystal evolution. By verifying the initial pH from 1.0 to 12.0, the morphology is evolved from single crystal, through sub‐micro crystallites, and finally to crystalline nanoparticles. The most influential factors in the morphology evolution are the initial pH level, the participation of surfactant‐template F127, and the change in pH during the reaction.
Refractive Index and Density Measurements for Selected Binary Protic‐Protic, Aprotic‐Aprotic, and Aprotic‐Protic Systems at Temperatures from 298.15 K to 308.15 K
Authors: El‐Dossoki Farid I.
Published: May 2015

The refractive indices (n) and the densities (ρ) of: (1) protic‐protic solvent mixtures (methanol‐ethanol, methanol‐porpanol, methanol‐butanol and ethanol‐water), (2) aprotic‐aprotic solvent mixtures (acetonitrile‐dimethylformamide, acetonitrile‐dimethylsulphoxide, and acetonitrile‐1,4‐dioxane) and (3) aprotic‐protic solvent mixtures (dimethylformamide, acetonitrile with water and some aliphatic alcohols) were measured experimentally at different temperatures (25, 30 and 35 °C). From the values of the measured refractive indices and densities, the excess refractive indices (nE), molar refractions (R), atomic polarization (PA), molar volumes (V), solvated radii (r) and polarizabilities (α) of the mixed solvents were calculated.

The results show that the solvent‐solvent interaction reaches maximum value at a definite mole fraction (x) of each solvent depending on its nature. Also, the excess refractive indices, densities and atomic polarizations are found to decrease as the temperature increases. On the other hand, the molar volumes, solvated radii, molar refractions and polarizabilities are found to increase as the temperature increases.
Synthesis of New Reagent Benzyloxybenzaldehydethiosemicarbazone (BBTSC): Selective, Sensitive and Extractive Spectrophotometric Determination of Pd(II) in Water Samples and Synthetic Mixtures
Authors: Narayana Suvarapu Lakshmi , Reddy Koduru Janardhan , Reddy Somala Adi Narayana , Kumar Jyothi Rajesh , Reddy Ammireddy Varada
Published: May 2015

A new reagent, benzyloxybenzaldehydethiosemicarbazone (BBTSC) was synthesized and a new method was developed for the simple, highly selective and extractive spectrophotometric determination of palladium(II) with BBTSC at wave length 365 nm. The metal ion formed a yellow colored complex with BBTSC in acetate buffer of pH 5.0, which was easily extractable into cyclohexanol with 1:1 (Metal: Ligand) composition. The method obeys Beer's law in the range of 5–60 ppm. The molar absorptivity and Sandell's sensitivity were found to be 0.4 × 104 Lt. mol−1 cm−1 and 0.02661 μg cm−2, respectively. The correlation co‐efficient of the Pd(II)‐BBTSC complex was 0.9657, which indicated an excellent linearity between the two variables. The repeatability of the method was checked by finding the relative standard deviation (RSD) (n = 10), which was 0.321% and its detection limit 0.016875 μg.mL−1. The instability constant of the method was calculated by Asmus' method as 3.5714 × 10−4. The interfering effect of various cations and anions were also studied. The proposed method was successfully applied for the determination of palladium(II) in synthetic and water samples. The results were compared with those obtained using an atomic absorption spectrophotometer, testing the validity of the method.
Development a New Method for the Determination of Chloropromazine in Trace Amounts by Fast Fourier Continuous Cyclic Voltammetry at an Au Microelectrode in a Flowing System
Authors: Norouzi Parviz , Ganjali Mohammad Reza , Farokhi Rohallah
Published: May 2015

In this study a new technique has been developed for the determination of chloropromazine in flow‐injection systems. The technique, named fast Fourier transformation continuous cyclic voltammetry (FFTCV), basically illustrates the benefits of sensitivity, selectivity, simplicity and low detection limit.

It is also important to refer to the positive points, presented only by the use of this technique. Firstly, it is no longer necessary to remove the oxygen from the test solution. Furthermore, the quick determination of any such compound in many chromatographic methods is possible. Thirdly, the corresponding detection limit is of sub‐nanomolar level. Additionally, a special computer based numerical method is also introduced for the calculation of the analyte signal and noise reduction. The electrode response was calculated in accordance with the partial and total charge exchanges on the electrode surface, after the background current subtraction from that of noise. The integration range of currents was set for all the potential scan ranges, including oxidation and reduction of Au surface electrode, to obtain a sensitive determination.

The performed experiments aimed at measuring the effects of different parameters on the method sensitivity. In the end of these measurements, it was concluded that the method was linear for the concentration range of 0.32–31900 pg/mL (r = 0.996) with a limit of detection and quantitation 0.1 and 0.32 pg/mL, respectively. For the achievement of these optimum results, the parameter values were set to 100 V/s for the scan rate, 0.4 s for accumulation time, 800 mV for accumulation potential and 2 for the pH.
NMR Studies of a Series of Shikimic Acid Derivatives
Authors: Zhang Ping , Huang Jian , Chen Fen‐Er
Published: May 2015

The investigations of the 1H and 13C resonances of a series of 9 shikimic acid derivatives were carried out using one‐ and two‐dimensional methods. 1H and 13C spectral data were assigned by DEPT, 1H‐1H COSY, HSQC, HMBC, and the stereo configuration was confirmed by 1D selective NOESY experiments.
An Improved Synthesis of Ceramide for Constructing α‐Galactosyl Ceramide Analogs
Authors: Yeh Chien‐Hung , Pan Si‐Der , Chen Shao‐Wei , Fu Zhi‐Wei , Chiang Li‐Wu , Yu Chung‐Shan
Published: May 2015

In spite of numerous synthetic routes to ceramide analogs, relatively few reports of the direct coupling of the unprotected phytosphingosine with the activated palmitic acid via amide bond formation are available. After purification by HPLC, the chromatogram indicated some impurities had not been removed during previous column chromatography. With the pure ceramides in hand, derivatization with the amino group for constructing libraries could be realized.
A Novel Spectrophotometric Method for the Determination of Zolmitriptan in Pharmaceutical Formulations
Authors: Raza Asad , Ansari Tariq Mahmood , Niazi Shahida Begum
Published: May 2015

A simple, rapid, cost effective and extraction‐free spectrophotometric method has been developed for the determination of zolmitriptan in pharmaceutical raw and dosage forms. The method is based on the charge‐transfer reaction of zolmitriptan in acetonitrile medium with 0.2% 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone to form a colored product peaking at 555 nm. Beer's law is obeyed in the concentration range 10‐250 μg mL−1 with molar absorptivity of 1.7 × 103 L mole−1 cm−1. The effects of variables such as reagent concentration, time of reaction, color stability and interferences have been investigated to optimize the procedure. The results have been validated analytically and statistically. The proposed method has been successfully applied for the determination of zolmitriptan in pharmaceutical formulations. Results indicate that the method is accurate, precise and reproducible (relative standard deviation < 2%).
Charge Transfer Complex Role in the Formation of Chlorobenzene in the γ‐Irradiated Carbon Tetrachloride‐Benzene System
Authors: Sife‐Eldeen KH. A. , Ebraheem S.
Published: May 2015

The formation of carbon tetrachloride‐benzene charge transfer complex was confirmed by UV and NMR spectrometric studies. A change in UV spectrum of benzene is observed upon addition of carbon tetrachloride. Whereas the appearance of new bands supports the formation of charge transfer complex. NMR study shows that, chemical shift of benzene pmr signal depends on the CCl4‐C6H6 molar ratio. This observation is another criterion for the formation of benzene‐carbon tetrachloride charge transfer complex. Job's Continuous Variation method indicates that a 2:1 CCl4‐C6H6 charge transfer complex (2:1 CTC) is formed. The association constants (K2:1) of (2:1 CTC) was found to be 0.0197 M−2. The maximum concentration of (2:1 CTC) was found to be in samples with 2:1 CCl4‐C6H6 molar ratio (33% benzene mole). On the other hand the maximum yield of chlorobenzene was obtained, also, upon radiolysis of CCl4‐C6H6 samples at a 2:1 molar ratio (33% benzene mole). Therefore, it could be concluded that (2:1 CTC) participates in the formation of chlorobenzene upon radiolysis of the benzene‐carbon tetrachloride system. This conclusion was supported by the dependence of the chlorobenzene yield of a γ‐irradiated carbon tetrachloride‐benzene system (2:1 molar ratio) on irradiation time according to a third order kinetic equation with a very good linearity (R2 = 0.9977). Accordingly, the rate constant for the chlorobenzene formation under this condition was found to be ≈ 5.5 × 10−7 L2.mol−2.h−1. We propose a radiation chemical mechanism in which the 2:1 CTC plays a role in the formation of chlorobenzene.
Theoretical Study on the Intermolecular Interactions between 1,1‐Diamino‐2,2‐Dinitroethylene and H2O
Authors: Sun Xiao‐Qiao , Ju Xue‐Hai , Xu Xiao‐Juan , Fan Xiao‐Wei
Published: May 2015

The density functional method was applied to the study of 1,1‐diamino‐2,2‐dinitroethylene (Fox‐7)/H2O dimer. All the possible dimers (1, 2 and 3), as well as the monomers, were fully optimized with the DFT method at the B3LYP/6‐311++G** level. The basis set superposition errors (BSSE) are 4.62, 4.07 and 3.45 kJ/mol, and the zero point energy (ZPE) corrections for the interaction energies are 7.94, 5.66 and 6.40 kJ/mol for 1, 2 and 3, respectively. Dimer 1 is the most stable, judged by binding energy. After BSSE and ZPE corrections, the greatest corrected intermolecular interaction energy of dimer 1 was predicted to be −29.36 kJ/mol. The charge redistribution mainly occurs on the adjacent N–H··· O atoms and N–O··· H atoms between submolecules. The oxygen in the nitro group acts as a moderate hydrogen acceptor as compared to water oxygen. Based on the statistical thermodynamic method, the standard thermodynamic functions, heat capacities (C0P), entropies (S0T) and thermal corrections to enthalpy (H0T), and the changes of thermodynamic properties on going from monomer to dimer over the temperature range 200.00‐700.00 K were predicted. It is energetically or thermodynamically favorable for Fox‐7 to bind with H2O and to form dimer 1 at room temperature.
The Fock Matrix Analysis for Atomic Orbitals in Molecular Orbitals I. A New Look on the Covalent Bond in H2?
Authors: Hsu Wen‐Yi , Lee Hsing‐Yi , Wang Shao‐Pin , Chang Tse‐Chiang
Published: May 2015

The character of the molecular orbitals can be better accounted for in terms of molecular adapted atomic orbitals and the Fock matrix expanded in these atomic orbital sets. A clean‐cut and unique criterion for the diradicals and the covalent bonds can be given for the molecular orbitals in both restricted and unrestricted Hartree‐Fock wavefunctions. Instead of the picture that overlap charge migrates into the bonding region, the new analysis displays another picture that the charge densities for the electrons with α and β spins give rise to two opposite spin density shifts. If the α one shifts from atom A toward atom B then it is vice versa for the β one. The spin density shifts proceed until the bonding molecular orbitals form.
A Straightforward Method for the Synthesis of Functionalized Trisubstituted Alkenes through Na2S/Al2O3 Catalyzed Knoevenagel Condensation
Authors: Heravi Majid M. , Bakhtiari Khadijeh , Taheri Shima , Oskooie Hossein A.
Published: May 2015

Na2S/Al2O3 catalyzed the Knoevenagel condensation between an aldehyde and an active methylene compound to yield various trisubstituted alkenes.
An Efficient Synthesis of Sulfonylhydrazides and Sulfonylsemicarbazides by Utilizing Alumina as a Catalyst
Authors: Safaei‐Ghomi Javad
Published: May 2015

Sulfonyl hydrazides and sulfonyl semicarbazides are readily prepared by the reacting of hydrazine derivatives with sulfonyl chlorides in the presence of basic alumina under solvent‐free conditions. Reaction of a sulfonyl chloride with t‐butylcarbazate, followed by hydrolysis provides the corresponding sulfonyl hydrazides in higher yield and shorter time than previously reported.
A New Ellagitannin from the Fruit of Phyllanthus Emblica L.
Authors: Yang Chun‐Bin , Zhang Fan , Deng Mei‐Cai , He Guang‐Yun , Yue Jian‐Min , Lu Run‐Hua
Published: May 2015

A new ellagitannin along with eight known compounds has been isolated from the ethanol extract of the fruit of Phyllanthus emblica L. The chemical structure of the new compound was established as Phyllanthunin (1) by HR‐ESI‐MS, 1D and 2D NMR spectroscopic analysis.
TBAF‐Mediated Dimerization Reaction of β,γ‐Unsaturated Arylketones
Authors: Chang Meng‐Yang , Hung Chin‐Yi , Lin Shiang‐Tsern
Published: May 2015

A simple and high‐yield method for the synthesis of several 1,5‐diaryl‐1,5‐dicarbonyl compounds has been established starting from TBAF‐mediated isomerization and dimerization reaction of β,γ‐unsaturated arylketones (allyl arylketones) with mono‐, di‐, and tri‐methoxy groups, which is derived from allylation of commercially available different benzaldehydes and followed by oxidation of the resulting secondary alcohols.
A Novel Inorganic Clathrate Generated through Arene‐Arene Interactions
Authors: Mao Shih‐Hsuan , Liu Shih‐An , Liao Fen‐Ling , Shiu Kom‐Bei
Published: May 2015

The direct mixing of CoCl2, sodium 2,6‐pyridinedicarboxylate (Na2(2,6‐pda)), KSCN, and 1,2‐bis(4‐pyridyl)ethane (bpye) in water at the ambient temperature afforded purple crystals readily. The crystal structure, as determined by X‐ray diffraction crystallography, consists of discrete inorganic [Co2(η3‐2,6‐pda)2(μ‐SCN)2(H2O)2] and organic bpye molecules. Adjacent dicobalt molecules are connected via intermolecular hydrogen bonds, to form one‐dimensional hydrophobic channels in the solid state, which serve as a host framework to incarcerate bpye guests inside. Every organic molecule attaches to four adjacent inorganic species via arene‐arene interactions. The facile approach in assembling the dicobalt and bpye molecules together into an inorganic clathrate is demonstrated.
Transfer Thermodynamics of Protein in Denaturing and Stabilizing Media
Authors: Chatterjee Someswar , Basumallick I.
Published: May 2015

Free energies of transfer (ΔGt) of RibonucleaseA (RNaseA) from water to aqueous solutions of urea (4 M, 6 M and 8 M), a protein denaturing solvent as well as ΔGt of RibonucleaseA, β‐Lactoglobulin, α‐Chymotripsin and ChymotrypsinogenA from water to aqueous glycerol (10%, 20%, 30% and 40%), a protein stabilizing solvent has been dissected into cavity term [ΔGt(cav)] and interaction term [ΔGt(int)]. The interaction free energy includes all types of interactions like hard‐soft, hydrogen bonding, electrostatic, etc. The cavity forming free energies have been calculated using the standard version of scaled particle theory (SPT) with well‐reported SPT parameters. It has been found that transfer free energies of cavity terms ΔGt(cav) for native protein from water to urea‐water and water to aqueous glycerol follow almost opposite trends. This primarily indicates there may be some correlation between cavity creation energies and protein denaturing and stabilizing ability of a solvent. The results are in agreement with those obtained from preferential binding coefficient studies in these media.
Ultrafast Spectroscopy Studies on Thickness Dependence of Acoustic Phonon Modes in Silver Nanoprisms
Authors: Yu Pyng , Shiu Ying‐Jen , Chen Yit‐Tsong , Lin Sheng‐Hsien
Published: May 2015

Time‐resolved transient absorption technique is used to investigate the thickness dependence of acoustic phonon modes of silver nanoprisms with two thicknesses, 7.8 ± 1.2 and 8.5 ± 0.69 nm, and a similar bisector length of 31.4 ∼ 31.6 nm. Coherent acoustic phonon signals are observed. A new acoustic phonon frequency within 7.81 cm−1 ∼ 11.7 cm−1 is found and this phonon mode is associated with the thickness of the nanoprism. Another phonon frequency between 1.95 cm−1 and 1.71 cm−1 is also observed, and its origin can be associated with the bisector length of the nanoprism.
Synthesis, Structure and Magnetic Properties of 1‐D Silver(I) Complexes with Benzoic Acids Bearing Ortho‐Imino Nitroxide and Para‐Nitronyl Nitroxide Radical Ligands
Authors: Lin Hsin‐Huang , Wei Ho‐Hsiang
Published: May 2015

Two new 1‐D silver(I) complexes, [Ag(I)1.5(IM‐oBA)(NO3)0.5] (1) and [Ag(I)(NIT‐pBA)] (2), (IM‐oBAH = 2‐(2‐carboxyphenyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazol‐1‐yloxyl, NIT‐pBAH = 2‐(4‐carboxyphenyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐3‐oxido‐H‐imidazol‐3‐ium‐1‐yloxyl) have been prepared and structurally characterized. Complexes 1 and 2 crystallized in the monoclinic space groups of C2/c and P21/c, respectively. In complex 1, the structure consists of trinuclear Ag(I) atoms with different linkages of IM‐oBA and nitrates. The trinuclear Ag(I) atoms are further coordinated to the neighbor IM‐oBA radicals via self‐assembly of the nitrogen atom of imine moiety and extended into formation of a polymeric chain. Complex 2 is constructed from a bis(carboxylato‐O,O')‐bridged centrosymmetric dimeric subunit and extended into a polymeric chain through self‐assembly coordination between metal ions and nitroxide groups of NIT‐pBA radicals. Temperature dependence of magnetic susceptibility measurements showed a weak ferromagnetic coupling between nitroxide radicals in 1 and 2 with J = 5.62 for 1 and 6.62 cm−1 for 2, respectively.
Heterodinuclear Replacement Complexation for Sensitive Determination of Iron Ion in Surface Water with Dibromocarboxyarsenazo
Authors: Zeng Teng , Pan Lu‐Ting , Gao Hong‐Wen
Published: May 2015

Dibromocarboxyarsenazo (DBCA) was used to complex Fe and Cu ions at pH 6.22, and complexes Cu(DBCA) and Fe(DBCA) were formed. Fe ion replaced Cu competitively from its dinuclear complex Cu(DBCA)Cu to form the heterodinuclear complex, Cu(DBCA)Fe. The light‐absorption ratio variation approach has been applied to the direct determination of Fe ions with a high selectivity and good sensitivity using heterodinuclear replacement complexation. The limit of detection of Fe is only 2.5 ng/mL. The results from the analyses of five Huangpu River (Shanghai) cross‐section samples indicate that Fe ions are from 5.0 to 39.2 μg/L with the recovery rates between 85.5 and 111.5%.
The Fock Matrix Analysis for Atomic Orbitals in Molecular Orbitals II. The Electronic Structure of N2 Molecules
Authors: Hsu Wen‐Yi , Lee Hsing‐Yi , Wang Shao‐Pin , Chang Tse‐Chiang
Published: May 2015

Weinhold's natural hybrid orbitals can be chosen as the molecular adapted atomic orbitals to build the canonical molecular orbitals of N2 molecules. The molecular Fock matrix expanded in the natural hybrid orbitals can reveal deeper insight of the electronic structure and reaction of the N2 molecule. For example, the magnitude of Fab can signify the bonding character of the paired electrons as well as the diradical character of the unpaired electrons for both σ‐ and π‐types. Discarding the concept of the overlap between non‐orthogonal atomic orbitals, the different orbitals for different spins in the unrestricted Hartree‐Fock wavefunction reveal that there are three pairs of opposite spin density flows between two atoms, which proceed until the bonding molecular orbitals form.
Applications of Carbohydrate‐Gold Nanoparticles for Volumetric Flow Measurements Using an Opto‐Acoustic Technique
Authors: Yang Chan‐Yi , Wei Chen‐Wei , Lin Yen‐Ping , Tseng Hsiao‐Chien , Wu Ya‐Na , Chen Chia‐Chun , Shieh Dar‐Bin , Li Pai‐Chi
Published: May 2015

Gold nanoparticles with carbohydrate ligands attached on their surface have been synthesized and characterized with various techniques. The new nanoparticle conjugates have shown great potentials as a contrast agent for opto‐acoustic imaging. Hemocompatibility measurements of human blood for the carbohydrate‐gold nanoparticles have shown that the conjugates are feasible for in vivo testing. Preliminary quantitative flow measurements using the conjugates were also studied in this work based on the indicator‐dilution theory. In vitro phantom experiments were designed and conducted, and results were discussed.
Interaction of Bovine Serum Albumin with N‐(4‐Ethoxyphenyl)‐N′‐(4‐Antipyrinyl)Thiourea (EPAT) Using Spectroscopies
Authors: Cui Feng‐Ling , Cui Yan‐Rui , Wang Jun‐Li , Fan Jing , Li Jian‐Ping , Lu Yan
Published: May 2015

The interaction between N‐(4‐ethoxyphenyl)‐N′‐(4‐antipyrinyl)thiourea (EPAT) and bovine serum albumin (BSA) was studied by fluorescence spectroscopy in combination with UV absorption spectroscopy. The intrinsic fluorescence of bovine serum albumin was quenched by EPAT through a static quenching procedure. The binding constants of EPAT with BSA were estimated according to the fluorescence quenching results at different temperatures. The thermodynamic parameters: enthalpy change (ΔH) and entropy change (ΔS) were calculated to be −10.69 kJ/mol and 42.64 J·mol−1·K−1 according to thermodynamic equations, respectively, and indicating that the binding force was suggested to be mainly a hydrophobic force. The effect of common ions on the binding constant was also investigated. A new fluorescence spectroscopy assay of the proteins was presented in this paper. The determination results of the proteins in bovine serum by means of this method were very close to those obtained using Coomassie Brilliant Blue G‐250 colorimetry.
Synthesis of Endo,Endo‐2.9‐Dihydroxypentacyclo‐[8.4.0.03,8.04,14.07,11]Tetradeca‐5,12‐Diene
Authors: Chou Teh‐Chang , Lin Gerng‐Horng , Wu Sen‐Ching , Bahekar Sushilkumar S.
Published: May 2015

The title compound 30 was synthesized starting from the endo,syn,endo Diels‐Alder adduct 3a of hexahydro‐5,6,7,8‐tetrachloro‐9,9‐dimethoxy‐5,8‐methanonaphthalene‐1,4‐diol diacetate 6 and 1,2,3,4‐tetrachloro‐5,5‐dimethoxycyclopentadiene (TDCp) in six steps, keyed upon a symmetry‐allowed [4+4] photocyclization of decahydro‐11,12‐dioxo‐[1,4;5,8]dimethanoanthracene‐9,10‐diol diacetate 22. The epimeric monoacetate 26 related to 22 was also synthesized and their thermolysis and photolysis were investigated. Oxidation of diol 30 afforded hexacyclic bridged hemiacetal 31 as a result of transannular reaction. The structure of hemiacetal 31 was analyzed by single‐crystal X‐ray crystallography.
Synthesis, Crystal Structure and Density Functional Studies on 1N‐Phenyl‐3‐(2,4‐Dichlorophenyl)‐5‐(4‐Chlorophenyl)‐2‐Pyrazoline
Authors: Zhao Pu‐Su , Guo Huan‐Mei , Wang Xian , Jian Fang‐Fang
Published: May 2015

1N‐Phenyl‐3‐(2,4‐dichlorophenyl)‐5‐(4‐chlorophenyl)‐2‐pyrazoline has been synthesized and characterized by elemental analysis, IR, UV‐Vis and X‐ray single crystal diffraction. Density functional calculations have been carried out for the title compound by using the B3LYP method with a 6‐311G** basis set. The calculated results show that the predicted geometry can reproduce well the structural parameters. The electronic absorption spectra calculated in the gas phase are better than those calculated in EtOH solvent to model the experimental electronic spectra. Natural Bond Orbital (NBO) analyses suggest that the above electronic transitions are mainly assigned to π → π* transitions. On the basis of vibrational analyses, the thermodynamic properties of the compound at different temperatures have been calculated, revealing the correlations between C0p, m, S0m, H0m and temperature.
Synthesis and Characterization of Novel Organosoluble Polychloro Substituted Aromatic Poly(Ether Ketone)s
Authors: Sheng Shou‐Ri , Mao Xue‐Chun , Pei Xue‐Liang , Liu Xiao‐Ling , Song Cai‐Sheng
Published: May 2015

A novel monomer of tetrachloroterephthaloyl chloride (TCTPC) was prepared by the chlorination of terephthaloyl chloride catalyzed by ferric chloride at 175‐180 °C for 10 h, and confirmed by FTIR, MS and elemental analysis. A series of new polychloro substituted poly(aryl ether ketone)s with inherent viscosities of 0.58‐0.65 dL/g have been prepared from TCTPC with aromatic ether monomers by electrophilic Friedel‐Crafts acylation in the presence of DMF with anhydrous AlCl3 as a catalyst in 1,2‐dichloroethane. Glass‐transition temperatures of these polychlorinated polymers ranged from 267 to 280 °C by DSC. The degradation temperature at 5% weight loss by TGA in nitrogen for these polymers ranged from 486 to 534 °C, and the char yields at 700 °C were 54‐65%. The polymers having a weight‐average molecular weight in the range of 65,900‐79,300 are all amorphous and readily soluble in polar solvents such as DMF, DMSO and NMP at room temperature. All the polymers formed transparent, strong, and flexible films, with tensile strengths of 86.1‐99.7 MPa, Young's moduli of 2.32‐3.35 GPa, and elongations at break of 10‐15%.
Insulin Surface Acoustic Wave Immunosensor Based on Immobilized C60/Anti‐Insulin Antibody
Authors: Chang Hung‐Wei , Shih Jeng‐Shong
Published: May 2015

Immobilized fullerene C60/anti‐insulin antibody was prepared and applied in shear horizontal surface acoustic wave (SH‐SAW) immunosensors to detect insulin in aqueous solutions. The immobilizations of anti‐insulin onto fullerene were studied through a C60/PVC coated SH‐SAW sensor system in liquid. The partially irreversible frequency response for an anti‐insulin antibody was observed by the desorption study, which implied that fullerene could chemically react with anti‐insulin. C60/anti‐insulin coating materials were successfully prepared and identified with an FTIR spectrometer. The C60/anti‐insulin coated SH‐SAW immunosensors were developed and applied for detection of insulin in aqueous solutions. Within the range of normal human insulin concentration, the SH‐SAW immunosensors immobilized with C60/anti‐insulin exhibited linear frequency responses to the concentration of insulin with a sensitivity of 130 Hz/pM. The SH‐SAW immunosensor immobilized with C60/anti‐insulin showed a detection limit of 0.58 pM for insulin in aqueous solution. The interference of various common bio‐species in human blood, e.g. urea, ascorbic acid, tyrosine, and metal ions, to the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was investigated. These common bio‐species interferences showed nearly no interference to the SAW immunosensors coated with C60/anti‐insulin. The reproducibility of the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was also investigated and is discussed.
Preparation of 1H‐1,2,3‐Triazoles by Cuprous Ion Mediated Cycloaddition of Terminal Alkyne and Sodium Azide
Authors: Lu Li‐Hui , Wu Jia‐Hao , Yang Chia‐Hsi
Published: May 2015

1H‐1,2,3‐triazoles can be prepared in good yield by the reaction of terminal alkyne and sodium azide in the presence of cuprous chloride at a temperature higher than 70°C. The alkyne is unactivated and the reaction has to be carried out under inert gas. At room temperature, the reaction first gives a Cu(I)‐azide complex which is converted to a Cu‐alkyne complex when the temperature is raised to higher than 70°C. The reaction of Cu(I)‐alkyne complex and azide ion dissociated from or coordinated to Cu(I) then gives 1H‐1,2,3‐triazoles.
Bis‐Bromine‐1,4‐Diazabicyclo[2.2.2]Octane (Br2‐DABCO) as an Efficient Promoter for One‐Pot Conversion of N‐Arylglycines to N‐Arylsydnones in the Presence of NaNO2/Ac2O Under Neutral Conditions
Authors: Ghasemnejad‐Bosra Hassan , Haghdadi Mina , Khanmohammade Omid , Gholipour Abdoreza M. , Asghari Gharibreza
Published: May 2015

Bis‐Bromin‐1,4‐diazabicyclo[2.2.2]octane (Br2‐DABCO)‐promoted one‐pot conversion of various N‐arylglycines to sydnones using a combination of NaNO2 and Ac2O has been achieved efficiently through N‐nitrosation followed by cyclization in high yields (90‐96%) under mild and neutral conditions.
Increased Conversion to 2,4,6‐Triarylpyrylium Salt: Aldol Cyclotrimerization of Acetophenone in BMImPF6 Ionic Liquid
Authors: Chuang Po‐Neng , Wu Tsao‐Dong , Liu Ling‐Kang
Published: May 2015

Substituted acetophenone 1 in BMImPF6 ionic liquid, heated at 120 °C for 24 h, produces β‐methylchalcone 2, triarylbenzene 3, and triarylpyrylium salt 4. BMImPF6 catalyzes the self‐aldol condensation of 1, whose cyclotrimerization gives an increased conversion to 4 at the expense of 3 normally obtained from the cyclotrimerization of 1 in common organic solvent.
Magnolol Encapsulated by Liposome in Inhibiting Smooth Muscle Cell Proliferation
Authors: Chen Calvin Yu‐Chian , Wu Chieh‐Hsi
Published: May 2015

Magnolol, a pure compound extracted from Magnolia officinalis, encapsulated by liposome was investigated for inhibiting vascular smooth muscle cell (VSMC) proliferation leading to restenosis by Percutaneous Transluminal Coronary Angioplasty (PTCA). 1,2‐Diacyl‐Sn‐glycero‐3‐phosphocholine (EPC) and 1,2‐dipalmitoyl‐Sn‐glycero‐3‐phosphocholine (DPPC) liposomes were utilized to encapsulate the magnolol in this study. The inhibitory efficiency of the liposome encapsulated magnolol on cell viability was higher than the pure magnolol. EPC liposome was found to have higher efficiency in inhibiting VSMCs than DPPC. The diameters of EPC and DPPC liposome which encapsulated magnolol became larger than pure EPC and DPPC liposomes. The photos from transmission electron microscopy (TEM) were demonstrated that the EPC and DPPC liposomes could be interfered by magnolol to form a homogeneous liposome. Addition of cholesterol to EPC and DPPC liposome could reduce the liposome diameter.
Computational Study of Hydrogen Bonding in Substituted Phenol‐Acetonitrile‐Water Clusters
Authors: José Cotuá V. , Sandra Cotes O. , Fernando Castro G. , Pedro Castro P. , Liadys Mora L.
Published: May 2015

The calculations for a water‐acetonitrile‐substituted phenols system and the comparison with the experimental parameters will be given. Here we study change in the nature of the interactions into the system with donor and acceptor electron substituents on the phenolic ring, the structures, relative energies and harmonic frequencies. The conformers showed a significant difference in the OH and CN band shift depending on the type of the hydrogen bond formed and the position of the substituent on the phenolic ring. The cyclical hydrogen bonds between water‐acetonitrile and substituted phenol OH are important evidence of the relative stability in the system under study.
Preparation and Application of Cholesteryl‐Benzo‐15‐Crown‐5/Cholesteryl Mixed Liquid Crystals
Authors: Shen Ya‐Chi , Shih Jeng‐Shong
Published: May 2015

Various mixed liquid crystals containing crown ether‐cholesteryl liquid crystal, benzo‐15‐crown‐5‐COO‐C27H45 (B15C5‐COOCh), with various common cholesteric liquid crystals, e.g., cholesteryl chloride, cholesteryl benzoate and cholesteryl palmitate, were prepared and studied using polarizing microscopy and differential scanning calorimetry. Investigating the concentration effect of B15C5‐COOCh in mixed liquid crystals revealed that the addition of B15C5‐COOCh resulted in wider phase transition temperature ranges of these cholesteryl liquid crystals. The stability of these B15C5‐COOCh/cholesteryl mixed liquid crystals was studied using comprehensive graphic molecular modeling computer programs (Insight II and Discover) to calculate their molecular energy and stability energy. The effect of salts, e.g. Na+, Co3+, Y3+ and La3+, on the transition temperature range of the mixed liquid crystals was also investigated. The crown ether cholesteric liquid crystal B15C5‐COOCh was applied both as a surfactant and an ion transport carrier to transport metal ions through liquid membranes. Cholesteryl benzo‐15‐crown‐5 exhibited distinctive characteristics of a surfactant and the critical micellar concentration (CMC) of the surfactant was investigated by the pyrene fluorescence probe method. Cholesteryl benzo‐15‐crown‐5 was successfully applied as a good ion transport carrier (Ionophore) to transport various metal ions, e.g. Li+, Na+, La3+, Fe3+ and Co3+, through organic liquid membranes. The transport ability of the cholesteryl benzo‐15‐crown‐5 surfactant for these metal ions was in the order: Co3+ ≥ Li+ > Fe3+ > Na+ > La3+.
Study on the Binding Characteristic of Methamidophos‐Specific Molecularly Imprinted Polymer and the Interactions between Template and Monomers
Authors: Shen Zhong‐Lan , Zhu Xiao‐Lan , Yang Jun , Cai Ji‐Bao , Su Qing‐De
Published: May 2015

A new molecularly imprinted polymer (MIP) was prepared using methamidophos (MAP) as the template molecule based on non‐covalent interaction. The complexes formed between template and monomers before polymerization were characterized by 1H NMR titration test, FT‐IR and UV spectrometry study. These studies indicated that a 1:2 molecular complex formed dominantly between MAP and functional monomers. A model mainly involving cooperative hydrogen interaction was proposed by exact placement of functional groups. Association constant was estimated to be 2.894 × 106 L2/mol2. When the initial concentration of MAP was 1.0 mmol L−1, the affinity capacity of MIP was 4.23 times that of NIP. The binding performance of MIP was modeled with the Freundlich isotherm (FI) and the total number of binding sites was calculated to be 33.97 μmol/g. The MIP showed great homogeneity with a heterogeneity index of m = 0.7356. The specificity of MIP was investigated by single‐analyte binding and molecularly imprinted solid‐phase extraction (MISPE) assays using MAP and other structurally related organophorous pesticides (OPPs). The results indicated that the MIP had a marked preference for MAP.
The Method for Analysis of Hydrocarbon Mixtures C1‐C5 by Capillary Column Gas Chromatography
Authors: Yang Feng‐Ke , Zhang Zhan‐Tao , Chen Fang
Published: May 2015

This study was carried out to determine low‐boiling point hydrocarbon mixtures C1‐C5 using gas chromatography supplied with a flame ionization detector (FID) and a low‐pole capillary column. The temperature of the column reached −30 centigrade and all components eluted within 4 minutes. Sufficient resolution was available for the components with low retentions. The limits of the relative standard deviations (RSD) were from 0.19% to 2.40%. The method was found to be suitable for the determination of natural gas, petroleum, environmental quality, etc.
H3PW12O40/SiO2: An Eco‐Friendly Alternative for the Stereo‐, Regio‐ and Chemoselective Claisen‐Schmidt Condensation
Authors: Mirjalili Bibi Fatemeh , Zaghaghi Zahra
Published: May 2015

H3PW12O40/SiO2 or (PW/SiO2) promotes the regio‐, stereo‐ and chemoselective Claisen‐Schmidt condensation with improved yields.
Synthesis and ABTS Radical, MMP‐1 Inhibitory Activity of CAPE Analogues
Authors: Chiang Chih‐Chia , Hsu Ling‐Yih , Chang Tsu‐Chung , Tsai Hou‐Jen
Published: May 2015

In the photoaging process of skin, the ultraviolet (UV)‐induced reactive oxygen species (ROS) is the key regulator of matrix metalloproteinase (MMPs) expression. In this study, a series of Caffeic acid phenethyl ester (CAPE) analogues were synthesized by conjugating the group VI elements (selenium, sulfur, oxygen)‐containing aliphatic alcohols to polyphenolic acids. Their biological activities were evaluated by in vitro testing of their radical scavenging activity the of ABTS [2,2′‐azinobis‐(3‐ethyl‐benzothiazoline‐6‐sulfonic acid)] radical and inhibitory effect against the matrix metalloproteinase‐1 (MMP‐1) activity of collagen degradation and cytotoxicity of a human dermal fibroblast skin cell. Our results suggest these compounds displayed moderate anti‐free radical, potent MMP‐1 inhibitory, and low cytotoxic activities.
PEG‐N2O4 System as an Efficient Reagent both for the Rapid Oxidation of Urazoles and 1,4‐Dihydropyridines under Nonaqueous Conditions
Authors: Zolfigol Mohammad Ali , Ghaemi Ezat , Madrakian Elaheh , Niknam Khodabakhsh
Published: May 2015

N2O4 was easily impregnated on polyethyleneglycol to give a stable reagent. Polyethyleneglycol‐N2O4 (PEG‐N2O4) system was used as an effective oxidizing agent for the oxidation of urazoles and bis‐urazoles to their corresponding triazolinediones and also for the aromatization of 1,4‐dihydropyridines into the corresponding pyridine derivatives under mild conditions at room temperature with good to excellent yields.
Monte Carlo Simulation of Microemulsion Phase Transitions by Solvent Accessible Surface Area
Authors: Behjatmanesh‐Ardakani Reza , Karimi Mohammad Ali , Nikfetrat Mehdi
Published: May 2015

Results of lattice Monte Carlo simulation are presented for the behavior of a mixture of oil‐water‐amphiphile in different conditions. For the first time, the phase transitions between different types of microemulsion are modeled, in a qualitative manner, using the concept of solvent accessible surface area. All of the simulations are run in canonical (N, V, T) ensemble. Simple cubic lattices with the dimension of 50 have been used to avoid any size or surface effects of the boxes. Periodic boundary conditions and excluded volumes are used to mimic the box of simulation as a bulk of solution. All of the results are in good qualitative agreement with previous theoretical and experimental results.
Prediction of GC Retention Indexes for Insect‐Produced Methyl‐Substituted Alkanes Using a Wavelet Neural Network
Authors: Atabati Morteza , Zarei Kobra
Published: May 2015

A quantitative structure‐property relationship (QSPR) study based on the wavelet neural network (WNN) technique was performed for the prediction of gas chromatography retention indexes of methyl‐substituted alkanes produced by insects. In addition to the simple structural descriptors, semi‐empirical quantum chemical calculations at the AM1 (Austin Model 1) level were used to find the optimum 3D geometry of the studied molecules and a numbers of descriptors were calculated with HyperChem and Dragon software. A stepwise MLR (Multiple Linear Regression) method was used to select the best descriptors, and the selected descriptors were used as input neurons in a wavelet neural network model. The average relative error was 2.2%.
Synthesis of (3,5‐Aryl/methyl‐1H‐Pyrazol‐1‐yl)‐(5‐Arylamino‐2H‐1,2,3‐Triazol‐4‐yl)Methanone
Authors: Cao Zi‐Ping , Quan Bin , Dong Heng‐Shan
Published: May 2015

Some new (3,5‐aryl/methyl‐1H‐pyrazol‐1‐yl)‐(5‐arylamino‐2H‐1,2,3‐triazol‐4‐yl)methanones were synthesized and characterized by 1HNMR, 13C NMR, MS, IR spectra data and elemental analyses or high resolution mass spectra (HRMS). During the procedure, Dimroth rearrangement was used in this synthesis.
Contributions of a Surface Hydrophobic Cluster to the Folding and Structural Stability of Ubiquitin
Authors: Chen Rita P.‐Y. , Liang Fu‐Cheng , Lee Chung‐Tien , Zerella Rosa , Chan Sunney I.
Published: May 2015

The role of the small exterior hydrophobic cluster (SEHC) in the strand region of the N‐terminal β‐hairpin of ubiquitin on the structural stability and the folding/unfolding kinetics of the protein have been examined. We introduce a Phe→Ala substitution at residue 4 in the strand region of the N‐terminal β‐hairpin of the ubiquitin. A peptide with the same amino acid sequence as the first 21 residues of the mutated ubiquitin has also been synthesized. The F4A mutation unfolds the hairpin structure of the peptide segment without disruption of the turn. The same mutation does not seem to affect the overall structure, but the stability of the mutated full‐length protein decreases by approx. 2 kcal/mol. Kinetically, the entire hairpin structure is implicated in the transition state during folding of the wild type protein. The rate of refolding is retarded by the F4A mutation in ∼80% of the protein molecules. The F4A substitution also increases the unfolding rate of the protein by 10 fold. Thus the hydrophobic side‐chain of Phe‐4 not only contributes to the stability of the hairpin, but also to the stability of the entire protein by forming a cluster together with the hydrophobic residues on the C‐terminal strand.
Synthesis and Structural Characterization of One‐Dimensional Cadmium(II) Coordination Polymers Containing Polydentate Nitrogen Ligands
Authors: Suen Maw‐Cherng , Wang Ju‐Chun
Published: May 2015

The reactions of Cd(NO3)2·4H2O with NH4SCN and 2,4‐dpa (2,4‐dpa = 2,4‐dipyridineamine) in CH3OH afforded the one‐dimensional coordination polymer [Cd(NCS)2(2,4‐dpa)2]n, 1, while reaction of Cd(NO3)2·4H2O with NH4SCN and PmPa (PmPa = 2‐(1‐piperazinyl)pyrimidine) in CH3OH gave complex of the type [Cd(NCS)2(PmPa)2]n, 2. Each of the 2,4‐dpa ligand in complex 1 is coordinated to the Cd2+ metal center through pyridyl nitrogen atoms to form the one‐dimensional chain structures. The distorted {CdN4S2} octahedral coordination geometry around Cd2+ center is completed by pairs of bidentate thiocyanato ligands. Complex 2 has the 1‐D arrangement constructed through one‐dimensional double μ(N,S) end‐to‐end bridging thiocyanato groups bridged Cd(II) chains interconnected through PmPa ligands.
AC Impedance Studies on the Relationship between the Fractal Characteristics and Electrochemical Properties of Poly(Para‐Phenylene) Film
Authors: Chen Wan , Liang Cheng‐Hao , Yie Yang , Wu Bo
Published: May 2015

The effects of experimental conditions on the fractal structure of electrosynthetic polyparaphenylene films were studied by electrochemical impedance spectroscopy. The results indicate that, at the potential range (0‐0.6 V), the film surface fractal dimension rises while the corresponding charge transfer resistances Rct decrease as charge increases. This is consistent with the oxidized behavior of the conducting polymer. As for the degradation of electrolytes, scanning electron microscopy observations of poly(para‐pheneylene) (PPP) film provide evidence of the close relationship between the degradation of electrolytes and the film morphology, also in good agreement with the electrochemical impedance results interpretation. The X‐ray photoelectron spectroscopic analysis results present that the relative oxygen content ratio (O/C) of the films increases with the times the electrolyte is used, which reveals that the degradation of the electrolyte may result in a compact and passivation PPP film.
Synthesis and Molecular Structure of New S‐Nucleosides of 5‐(4‐Pyridyl)‐4‐Aryl‐4H‐1,2,4‐Triazole‐3‐Thiols
Authors: Zhang Huan‐Huan , Hu Xiu‐Qin , Fan Gui‐Fang , Xu Peng‐Fei
Published: May 2015

The synthesis of some new S‐nucleosides of 5‐(4‐pyridyl)‐4‐aryl‐4H‐1,2,4‐triazole‐3‐thiols (4a‐n) is described. Direct glycosylation of (4a‐n) with tetra‐O‐acetyl‐α‐D‐glucopyranosyl bromide in the presence of potassium hydroxide followed by deacetylation using dry ammonia in methanol gave the corresponding 3‐S‐(ñ‐D‐glucopyranosyl)‐5‐(4‐pyridyl)‐4‐aryl‐4H‐1,2,4‐triazoles (6a‐n) in good yields. All the compounds were fully characterized by means of 1HNMR, 13C NMR spectra and elemental analyses. To assist in the interpretation of the spectroscopic data, the crystal structure of 3‐S‐(2′,3′,4′,6′‐tetra‐O‐acetyl‐β‐D‐glucopyranosyl)‐5‐(4‐pyridyl)‐4‐phenyl‐4H‐1,2,4‐triazole (5a) was determined by X‐ray diffraction.
Synthesis of 2‐[4‐(Imidazolin‐2‐Ylideneamino)Benzyl]‐Indan‐1‐Ones as Novel Potent Prostacyclin Antagonists
Authors: Chern Ching‐Yuh , Yek Yung‐Lee , Chen Yu‐Lin , Kan Wai‐Ming
Published: May 2015

Prostacyclin is involved in many pathological conditions, such as sensitization of inflammation induced pain and isovolumetic distention. Therefore, antagonism of prostacyclin action may be useful in the alleviation of these conditions. In this study, novel potent prostacyclin antagonists, 2‐[4‐(imidazolin‐2‐ylideneamino)benzyl]‐indan‐1‐ones were synthesized from their respective substituted indanones in three steps. The construction of the amino‐imidazole moiety of these derivatives is achieved by using in situ generation of chloro‐imidazole and reaction with their respective anilines. Thus, these N‐substituted 2‐imidazolines can be prepared safely and efficiently. Moreover, these compounds show potent prostacyclin antagonistic activity by inhibition of prostacyclin agonist induced ERK1/2 phosphorylation in human erythroleukemia cells. Moreover, we observed an increase in activity with the increase in electro‐donating property of the substitution on the indanone aromatic ring. Prostacyclin antagonists with increased potency may be designed based on these findings. These compounds may also be invaluable tools for the study of the physiological functions of prostacyclin.
Silica Sulfuric Acid and Al(HSO4)3: As Efficient Catalysts for the Formylation of Alcohols by Using Ethyl Formate under Heterogeneous Conditions
Authors: Zolfigol Mohammad Ali , Chehardoli Gholamabbas , Dehghanian Mina , Niknam Khodabakhsh , Shirini Farhad , Khoramabadi‐Zad Ahmad
Published: May 2015

A mixture of ethyl formate and a catalytic amount of silica sulfuric acid or Al(HSO4)3 as suitable formylating systems can formylate various alcohols to their corresponding formate ester derivatives under mild, nearly neutral and heterogeneous conditions at room temperature with good to excellent yields.
A Convenient and Versatile Method for the Preparation of α‐Hydroxymethyl Ketone Derivatives from the Corresponding Allyl Silyl Ethers or Allyl Carboxylates
Authors: Hon Yung‐Son , Wong Ying‐Chieh , Wu Kuo‐Jui
Published: May 2015

The ozonolysis of 1‐substituted allyl silyl ethers or 1‐substituted allyl carboxylates followed by treatment with bases gave the corresponding α‐silyloxymethyl‐ or α‐acyloxymethyl‐ketones in good yields. It is proposed to proceed via the corresponding α‐silyloxy‐ or α‐acyloxyaldehydes intermediates followed by 1,4‐group migration. The results of theoretical calculations are applicable to explain the experimental results.
Ethyl Xanthate and Propyl Xanthate as Activators and Inhibitors of Mushroom Tyrosinase in Different Concentrations
Authors: Saboury A. A. , Alijanianzadeh M.
Published: May 2015

The effect of ethyl xanthate(I) and propyl xanthate(II) on the kinetics of hydroxylation by mushroom tyrosinase (MT) has been investigated at 20°C in 10 mM phosphate buffer solution, pH 6.8. 4‐[(4‐Methyl‐phenyl)azo]‐phenol (MePAPh) was used as a synthetic substrate for the enzyme for cresolase reaction. The results show that ethyl xanthate and propyl xanthate can activate or inhibit the cresolase activity of mushroom tyrosinase depending on the concentration of these effectors. Both I and II act uncompetitive at relatively high concentrations (20‐50 μM). The inhibition constant (Ki) values for I and II are 13.8 and 11 μM, respectively. However, both I and II act as activators at relatively low concentrations (0‐11.5 μM). Activation of the enzyme in low concentrations of xanthates arises from increasing the affinity of binding for the substrate as well as increasing the enzyme catalytic constant. The activation constant (Ka) values for I and II are 1.88 and 2.68 μM, respectively. The enzyme has two distinct sites for both effectors. The first one is a high‐affinity activation site and the other is a low‐affinity inhibition site.
Synthesis of Polysubstituted Quinolines Using Cyanuric Chloride as a Catalyst Under Aqueous Conditions
Authors: Bandgar Babasaheb P. , More Parmeshwar. E. , Kamble Vinod T.
Published: May 2015

A mild, eco‐friendly and efficient route for the synthesis of quinolines and polycyclic quinolines via Friedländer annulation using cyanuric chloride as a catalyst under aqueous conditions is described.