bluuebunny/crossref_metadata_2025_split huggingface dataset:
Triiodide PVC Membrane Electrode Based on a Charge‐Transfer Complex of Iodine with Ditertbutyl‐Dicyclohexyl‐18‐Crown‐6
Authors: Khayatian Golamreza , Karoonian Fatemeh Salehi 
Published: May 2015

AbstractA new triiodide ion‐selective electrode based on a charge‐transfer complex of iodine with ditertbutyl‐dicyclohexyl‐18‐crown‐6 (t‐Bu)2DC18C6 as membrane carrier was prepared. The electrode has a linear dynamic range from 6.3 × 10−3‐5 × 10−6 with a Nernstian response of 58.6 ± 1 mV decade−1 and a detection limit of 1.3 × 10−6 M. The response time of the sensor was 25 s. The membrane could be used for two months without any divergence in potentials. The electrode exhibits an anti‐Hofmeistetr selectivity sequence with a preference for triiodide at pH 2.0‐10.0. The response mechanism of the electrode was investigated by Uv‐Vis spectroscopic technique. The electrode can be used for the determination of ascorbic acid in orange juice.
Dowex as Reusable Acidic Polymeric Catalyst in the Efficient and Regioselective Conversion of Epoxides into β‐Hydroxy Thiocyanates under Solvent Free Conditions
Authors: Kiasat Ali Reza , Fallah‐Mehrjardi Mehdi 
Published: May 2015

AbstractA convenient and efficient procedure for the regioselective ring opening of epoxides in the presence of Dowex (strongly acidic cationic exchange resin), as reusable eco‐friendly catalyst under solvent free conditions is described. Thus, several β‐hydroxy thiocyanates, useful intermediates toward pharmaceutical and biologically active molecules, are easily obtained in high isolated yields.
Mesoporous Molecular Sieve MCM‐41 as a Novel and Efficient Catalyst to Synthesis of 2‐Substituted Benzimidazoles
Authors: Heravi Majid M. , Baghernejad Bita , Oskooie Hossein A. , Malakooti R. 
Published: May 2015

Abstracto‐Phenylenediamine derivatives readily react with benzoyl chloride derivatives in the presence of MCM‐41 as catalyst to yield 2‐substituted benzimidazoles in very good yields.
Purification and Characterization of Lectins from Jute (Chorchorus olitorius) Leaves
Authors: Khan M. M. H. , Rahman A. T. M. Mijanur , Uddin Md. Salim , Khatun Shahanaz , Pervin F. , Absar N. 
Published: May 2015

AbstractThree lectins were isolated from an extract of jute leaves (Chorchorus olitorius) and purified by gel filtration on Sephadex G‐50 of the 100% ammonium sulfate saturated crude extract, followed by ion‐exchange chromatography on DEAE‐cellulose were designated as JLL‐1, JLL‐2 and JLL‐3. All the lectins were homogeneous as judged by SDS‐polyacrylamide slab gel electrophoresis and gave single bands. The molecular weights of the three lectins were estimated by the same method were 35000, 38000 and 42000, respectively. The lectins specifically agglutinated rat red blood cells. The agglutination of JLL‐1 was inhibited by D‐mannose/D‐glucose and their derivatives, whereas D‐galactose was found to be the potent inhibitor for the agglutination of JLL‐2 and JLL‐3. The lectins were glycoprotein in nature with a neutral sugar content of 1.3%, 1.2% and 0.8% for JLL‐1, JLL‐2 and JLL‐3, respectively. The hemagglutinating activity of JLL‐2 was also investigated after the treatment of physico‐chemical agents. The lectin showed maximum activity between the range of pH 7.2–8.0 and the range of temperature of 20‐30 °C. The activity of lectin decreased after treatment with a higher concentration of acetic acid and urea. In the presence EDTA the activity was inhibited while the presence of Ca+2, Mn+2 and K+ increased the activity of the lectin moderately.
Aluminium Nitrate/Silica Sulfuric Acid/Bromide Ion: As an Effective and Catalytic Oxidizing Media for the Selective Oxidation of Sulfides to Sulfoxides
Authors: Ghorbani‐Choghamarani Arash , Goudarziafshar Hamid , Hajjami Maryam , Soltani Jinoos 
Published: May 2015

AbstractVarious types of sulfides are chemoselectively oxidized to the corresponding sulfoxides by treatment of Al(NO3)3.9H2O, silica sulfuric acid and a catalytic amount of NaBr in the presence of wet SiO2 (50% w/w) in CH2Cl2 at room temperature. The catalytic oxidation procedure is very simple and the products are easily isolated in good yields.
Multifunctional Catalysis of Heteropoly Acid: One‐Pot Synthesis of Quinolines from Nitroarene and Various Aldehydes in the Presence of Hydrazine
Authors: Hekmatshoar Rahim , Sajadi Sodeh , Sadjadi Samaheh , Heravi Majid M. , Beheshtiha Yahya S. , Bamoharram Fatemeh F. 
Published: May 2015

Abstract12‐Molybdophosphoric acid catalyzed transfer hydrogenation of nitroarene by hydrazine in a homogeneous phase. This catalytic system was applicable to one‐pot quinolines synthesis in the presence of various aldehydes in water. This method provides a new and efficient protocol in terms of mild reaction conditions, clean reaction profiles, small quantity of catalyst, and simple work‐up procedure.
A New Steroid Glycoside Derivative from Acorus Calamus L.
Authors: Dong Wei‐Wei , Jiao Wei , Deng Mei‐Cai , Yang Chun‐Bin , Yue Jian‐Min , Lu Run‐Hua 
Published: May 2015

AbstractA new steroid glycoside derivative, 4′‐O‐docosanoyl‐3‐O‐β‐D‐glucosyl‐sitosterol, along with six known steroids has been isolated from the ethanol extract of the rhizoma of Acorus calamus L. The structures of the new and known compounds were established on the basis of extensive 1D and 2D NMR spectral data.
Synthesis and Characterization of Novel Monoazo Naphthalimide Disperse Dyes Containing Carboxylic Acid Group with High Heat Fastness Properties
Authors: Kiakhani Moosa Sadeghi , Gharanjig Kamaladin , Arami Mokhtar , Mokhtari Javad , Mahmoodi Niyaz Mohammad 
Published: May 2015

AbstractA group of novel monoazo disperse dyes containing carboxylic acid‐1,8‐naphthalimide group has been synthesized. All intermediates and dyes were purified by recrystalization and the column chromatography method. The purified products were characterized by 1H NMR, 13C NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Spectrophotometric investigations of the synthesized dyes in different solvents were carried out in order to obtain their absorption maxima, molar extinction coefficients and solvatochromic effects. The absorption maxima of the synthesized dyes in acetone varied (513‐549 nm) and the molar extinction coefficient was (17405‐38939 l/mol cm). By changing the media from chloroform to DMF, the solvatochromism effect for all dyes increased. Dispersion of the synthesized dyes was prepared in water containing dispersing agent and applied to polyester fabrics. The dyed fabrics showed that all of the synthesized dyes were suitable for coloring polyester fibers, producing deep red to bluish red with very good fastness properties.
The Regiospecific Synthesis of Some New 3,5‐Disubstituted Isoxazoles
Authors: Edjlali Ladan 
Published: May 2015

AbstractThe compounds with isoxazole moiety have many pharmacological, biological and industrial applications, specifically their antiviral activity. In this research work, seven new compounds of 3,5‐disubstituted isoxazoles were synthesized. Propargyl alcohol (1) reacted with benzoyl chloride to give propargylphenylcarboxylate (2). Then, the aldehydes (3a‐3g) were converted to the related oximes (4a‐4g) and nitrileoxides in situ by NaOCl, consequently. Reaction of compound 2 with nitrileoxides in a [3+2] cycloaddition reaction gave regiospecifically isoxazoles (5a‐5g). 1H NMR, 13C NMR, FT‐IR, and elemental analyses confirmed the structure of the synthesized compounds.
Metal Hydrogen Sulfates M(HSO4)n: As Efficient Catalysts for the Synthesis of Quinoxalines in EtOH at Room Temperature
Authors: Niknam Khodabakhsh , Zolfigol Mohammad Ali , Tavakoli Ziba , Heydari Zahra 
Published: May 2015

AbstractA convenient method for the synthesis of quinoxalines catalysed by metal hydrogen sulfates by the reaction of 1,2‐diamino compounds and 1,2‐dicarbonyl compounds in ethanol as solvent at room temperature is reported.
A New Singular Matrix Method for Balancing Chemical Equations and Their Stability
Authors: Risteski Ice B. 
Published: May 2015

AbstractIn this work is given a new singular matrix method for balancing new classes of chemical equations which reduce to an n × n matrix. The method offered here is founded by virtue of the solution of a homogeneous matrix equation by using of Drazin pseudoinverse matrix. The method has been tested on many typical chemical equations and found to be very successful for the all equations in our extensive balancing research. This method works successfully without any limitations. Chemical equations treated here possess atoms with fractional oxidation numbers. Also, in the present work are analyzed some necessary and sufficient criteria for stability of chemical equations over stability of their reaction matrices.
Synthesis of Gold Nanosheets through Thermolysis of Mixtures of Long Chain 1‐Alkylimidazole and Hydrogen Tetrachloroaurate(III)
Authors: Hsu Shih‐Jen , Lin Ivan J. B. 
Published: May 2015

AbstractMicron‐sized gold nanosheets were produced through thermolysis of a mixture composed of 1‐octa‐decanylimidazole (C18‐im) and HAuCl4 in a molar ratio of 4:1 at 200 °C for 1 h. Effects of the molar ratio of [18‐im]/[HAuCl4], the reaction temperature, and the N‐alkylimidazole chain length were studied. Adjusting the molar ratio of [C18‐im]/[HAuCl4] can tune the morphology and size of the nanostructures; the effect of reaction temperature is minimum; while using long chain imidazole tends to favor the formation of nanosheets, using 1‐methylimidazole (C1‐im) produces micron‐sized polyhedra. The growth mechanism of these nanostructures was proposed. C18‐im functions both as a templating and capping agent and favors the growth of nanosheets. On the other hand, C1‐im functions only as a capping agent and thus favors the formation of polyhedra, especially octahedra.
Study on the Role of Metal Oxides in Desulphurization of Some Petroleum Fractions
Authors: Shakirullah M. , Ahmad Imtiaz , Ishaq M. , Ahmad Waqas 
Published: May 2015

AbstractMetal oxides are highly reactive towards the compounds of sulphur, particularly thioles. A comparative study was made of the desulphurization potential of various metal oxides such as MnO2, PbO2, ArO3, Al2O3, MgO2, ZnO2 and silica on reaction with Jhal Magsi crude oil and its distillate fractions, i.e., kerosene and diesel oil. The effect of time was also studied and the desulphurization was performed for time durations of one hour, three hours and six hours. The analysis of the residual fractions indicated that significant sulphur depletion occurred with lead oxide and manganese dioxide in the one‐hour and three‐hour reaction times in all three samples. Lead oxide (PbO2) brought about a maximum desulphurization of 60.28% in the case of crude oil, 54.54% in the case of diesel oil and 52.57% in the case of kerosene oil in a 01 h reaction time. Similarly, manganese oxide (MnO2) caused a maximum desulphurization of 58.55% in the case of crude oil, 49.38% in the case of diesel oil and 53.30% in case of kerosene oil in a 3 h reaction time. The rest of the metal oxides also exhibited good sulphur removal activity, but their performance is not as noteworthy as in the cases of PbO2 and MnO2.
Synthesis and Antiproliferative Activity of 6‐Ferrocenyl‐3‐Substituted 7H‐1,2,4‐Triazolo[3, 4‐b]‐1,3,4‐Thiadiazines
Authors: Han Yin , Wang Qin , Du Yu‐Ping , Lv Ming‐Hua , Hui Xin‐Ping 
Published: May 2015

AbstractFive new 6‐ferrocenyl‐3‐substituted 7H‐1,2,4‐triazolo[3, 4‐b]‐1,3,4‐thiadiazines (3a‐e) have been synthesized and characterized on the basis of elemental analyses and spectral data. The antiproliferative activities were examined in two human cell lines (BJ and HT 1080) with the acid phosphatase assay. The results showed that all compounds could reduce cell viability. The significant difference between the two cell lines was that fibrosarcoma HT 1080 cells could indeed be more susceptible to the compounds than the normal fibroblast BJ cells.
Supported Preyssler Nanoparticles in Synthesis of 1,3‐Diaryl‐5‐Spirohexahydropyrimidines
Authors: Heravi Majid M. , Sadjadi Samaheh , Sadjadi Sodeh , Oskooie Hossein A. , Shoar Rahim Hekmat , Bamoharram Fatemeh F. 
Published: May 2015

AbstractSilica‐supported Preyssler nanoparticles (H14[NaP5W30O110])/SiO2 are used as a new and recyclable catalyst for the preparation of 1,3‐diaryl‐5‐spirohexahydropyrimidines via a one‐pot condensation of anilines, formaldehyde, and cyclohexanone.
1,3–Dichloro‐5,5–Dimethylhydantoin (DCH) and Trichloromelamine (TCM) as Efficient Catalysts for the Chemoselective Trimethylsilylation of Hydroxyl Group with 1,1,1,3,3,3–Hexamethyldisilazane (HMDS) Under Mild Conditions
Authors: Ghorbani‐Choghamarani Arash , Amani Kamal , Zolfigol Mohammad Ali , Hajjami Maryam , Ayazi‐Nasrabadi Roia 
Published: May 2015

AbstractA highly convenient method for the trimethylsilylation of alcohols and phenols via treatment by hexamethyldisilazane in the presence of 1,3–dichloro‐5,5–dimethylhydantoin (DCH) and/or trichloromelamine (TCM) as a catalyst has been developed. A wide variety of hydroxyl groups were selectively protected in CH2Cl2/CH3CN under mild conditions.
Electrochemical Studies on the Interaction of Heparin with Phenosafranine and Its Analytical Application
Authors: Hui Ni , Sun Wei , Ding Ya‐Qin , Zhao Na , Jiao Kui 
Published: May 2015

AbstractThe interaction of phenosafranine (PSF) with a glycosaminoglycan of heparin (Hep) in aqueous solution was characterized by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) in this paper and further used for Hep detection. In pH 1.5 Britton‐Robinson (B‐R) buffer solution PSF had a well‐defined voltammetric reductive peak at −0.256 V (vs SCE), and the electrochemical response was faded by the addition of Hep. Cyclic voltammetric experiments indicated that the electrochemical behaviors of free PSF didn't change no matter whether Hep was presented in PSF solution or not. Based on the decrease of the peak current, a second order derivative linear sweep voltammetry was used to establish a sensitive electroanalytical method for Hep. The peak current was proportional to the concentration of Hep in the range of 0.7∼20.0 mg L−1, demonstrating that this method was suitable for routine Hep detection. Under optimal conditions, the linear regression equation for the Hep determination was ΔIp”(nA) = 46.30 C (mg L−1) + 343.31 (n = 11, γ = 0.991) with a detection limit of 0.08 mg L−1(3σ). The established method was further successfully applied to heparin sodium injection samples determination. The interaction mechanism was discussed based on the electrostatic attraction of the negatively charged Hep with the positively charged PSF, and the stoichiometry of Hep‐PSF was calculated by the voltammetric method.
Determination of Cr(VI) with Selective Sensing of Cr(VI) Anions by a PVC‐Membrane Electrode Based on Quinaldine Red
Authors: Yari Abdollah , Bagheri Habibollah 
Published: May 2015

AbstractA dichromate‐selective PVC‐membrane electrode based on Quinaldine Red (an acridinium derivative) is described. The electrode exhibits rapid (< 30 s) and linear response to the activity of Cr(VI) anions in the range of 5.2 × 10−6 −1.0 × 10−1 M dichromate with the limit of detection 2.5 × 10−6 Mof Cr2O72−. The sensor is used as an indicator electrode in potentiometric determination of Cr(VI) anions and is also suitable for end‐point indication in the titrations of proper metal ions with dichromate under laboratory conditions. The proposed electrode has been applied to the direct potentiometric determination of Cr(VI) anions in water samples with satisfactory results.
The Chemical Constituents of Polypodium Niponicum
Authors: Shen Tong , He Yi‐Lin , Wen Cheng‐Wu , Zheng Shang‐Zhen 
Published: May 2015

AbstractThree new steroids named as shuilongguine I (1), shuilongguine II (2) and shuilongguine III (3), together with eleven known compounds were isolated from Polypodium niponicum (Chinese name “Shuilonggu”, Berberidaceae). Their structures were deduced by spectroscopic methods and 2D NMR experiments.
Simultaneous Determination of Total Nitrogen and Metal Elements in Tobaccos by High Performance Ion Chromatography
Authors: Cai Ji‐Bao , Wang Su‐Fang , Tang Ping‐Ping , Su Qing‐De 
Published: May 2015

AbstractA simple method, developed primarily for simultaneous determination of total nitrogen and inorganic cations by high performance ion chromatographic (HPIC), was optimized for digestion of flue‐cured tobaccos, and compared with the traditional Kjeldahl method and atomic absorption spectrometry (AAS). Nitrogen determination by either Dumas method or Kjeldahl method is time‐consuming and tedious. Metal elements determination by either inductively coupled plasma‐mass spectrometry (ICP‐MS) or AAS may be more expensive and requires specialist equipment. The use of HPIC to simultaneous determine total nitrogen as ammonium ion and metal elements as inorganic cations after sample digestion significantly improves the speed of the analysis compared with the conventional methods. The cation‐exchange column and suppressed conductivity detector was used for determination of ammonium and inorganic cations in the presence of the elevated levels of sulfuric acid found in digested sample. The propsoed digestion method was accurate and precise, and required little investment. The determination of ammonium and inorganic cations was linear from 15 pg·L−1 up to 25 ng·L−1. The results obtained by the HPIC method were compared with those for the conventional methods approach for the determination of total nitrogen and metal elements. The application of the HPIC method is also demonstrated for a variety of other plant samples matrices.
Synthesis of Polynucleotide Modified Gold Nanoparticles as a High Potent Anti‐Cancer Drug Carrier
Authors: Wu Ching‐Ming , Wu Ping‐Ching , Wang Yun‐Han , Li Tsung‐Ju , Yang Li‐Xing , Wu Ya‐Na , Yang Hsi‐Yuan , Shieh Dar‐Bin 
Published: May 2015

AbstractGold nanoparticles have been developed for the photoacoustic imaging, delivery of genes and laser induced photothermal therapy. In this study, we have developed oligonucleotide conjugated gold nanoparticles as the carrier for simultaneous DNA and anti‐cancer nucleoside delivery. The polynucleotidenanoparticle complex presented higher capacity in carrying 5‐FU anti‐cancer compounds than the original gold particles. The hydrodynamic size of the gold nanoparticles increased from 25 to 35 nm with an increase in the negative surface charge from −9.58 to 21.66 mV after polynucleotide conjugation and drug loading. A positive association between environmental pH and drug release was observed in PBS, which implied their potential use in the controlled localized drug release in the lower GI tract. The MTT assay revealed dose dependent cytotoxicity to colon cancer cell line than free compounds. These results suggest the potential use of this new polynucleotide‐gold nanoparticles complex as the environmental controlled anti‐cancer nanocapsule, especially suitable for per oral colon cancer chemotherapy.
Zeolite Nanoparticle Modified Carbon Paste Electrode as a Biosensor for Simultaneous Determination of Dopamine and Tryptophan
Authors: Balal Khalilzadeh , Mohammad Hasanzadeh , Bahareh Bakhoday , Ali Babaei , Maryam Hajjizadeh , Mozhgan Zendehdel 
Published: May 2015

AbstractA new chemically modified electrode is constructed based on an iron(III) doped zeolite modified carbon paste electrode (Fe3+Y/ZCME). The electrode was evaluated as a sensor for sub‐micromolar determination of tryptophan (Trp) and dopamine (DA). The measurements were carried out using the differential pulse voltammetry (DPV) method in a phosphate buffer solution with pH = 5. The prepared modified electrode shows voltametric responses with high sensitivity and stability for DA and Trp in optimal conditions. The analytical performance of this sensor has been evaluated for detection of DA and Trp in human serum.
Chloroferrate(III) Ionic Liquid as Recyclable Catalyst for the Acetylation of Alcohols and Phenols and for 1,1‐Diacylation of Aldehydes
Authors: Wang Dong‐Sheng , Li Gui‐Yun , Peng Yan‐Qing 
Published: May 2015

AbstractA Lewis acidic ionic liquid, [bmim][FeCl4], was employed to catalyze acetylation of alcohols and phenols, and the conversion of aldehydes to corresponding 1,1‐diacetates without conventional organic solvents. The catalyst is easily available, water‐tolerant, recoverable and easy to handle.
Vapour Phase Hydrogenation of Cinnamaldehyde over Nano Ni and Ni/SiMCM‐41 Catalysts
Authors: Jao Kuang‐Yu , Liu Kang‐Wen , Yang You‐Hsiang , Ko An‐Nan 
Published: May 2015

AbstractNi nanoparticles (Ni(1) and Ni(2)) and Ni loaded SiMCM‐41 (15Ni/SiMCM‐41) were prepared and characterized with XRD, TEM, N2 adsorption, CO chemisorption, and H2‐TPR. The Ni specific surface area followed the order of 15Ni/SiMCM‐41 > Ni(1) >> Ni(2), whereas the Ni particle size exhibited the opposite trend. These catalysts were utilized for vapour phase hydrogenation of cinnamaldehyde at 1 atm and 200 °C in a fixed‐bed, down flow reactor. The main products include hydrocinnamaldehyde, styrene, ethylbenzene, and 2‐phenyl‐1‐propanol. The catalytic activity decreased in the same order as that of Ni specific surface areas. The SiMCM‐41 support possessed very large surface area, leading to enhanced dispersion and specific surface area of Ni nanoparticles. As a result, the 15Ni/SiMCM‐41 catalyst exhibited the highest activity. Based on the investigation of reaction pathways, it is important to emphasize that both hydrogenation and hydroelimination of formaldehyde (hydrodeformylation) occur in the vapour phase reaction.
Solution Structure and Model Membrane Interactions of P‐113, a Clinically Active Antimicrobial Peptide Derived from Human Saliva
Authors: Yip Bak‐Sau , Chen Heng‐Li , Cheng Hsi‐Tsung , Wu Jiun‐Ming , Cheng Jya‐Wei 
Published: May 2015

AbstractP‐113, AKRHHGYKRKFH‐NH2, was derived from human saliva and found to possess clinical activity against fungus infections in HIV patients with oral candidiasis. We have determined the solution structure of P‐113 bound to membrane‐mimetic SDS micelles by two‐dimensional NMR methods. The SDS micelle‐bound structure of P‐113 adopts an α‐helical segment and the positively charged residues are clustered together to form a hydrophilic patch. A variety of biophysical and biochemical experiments, including circular dichroism, fluorescence spectroscopy and microcalorimetry, were used to show that P‐113 interacted with negatively charged phospholipid vesicles and induced dye release from these vesicles. However, its dye leakage efficiency is much less than the results of previously reported antimicrobial peptides. These results suggest that the antimicrobial activity of P‐113, unlike other antimicrobial peptides, may act not only through binding to and destabilization of the microbial membrane but also through a specific protein receptor on the microbial cell surface.
Cyanoacetanilides Intermediates in Heterocyclic Synthesis. Part 5: Preparation of Hitherto Unknown 5‐Aminopyrazole and Pyrazolo[1,5‐a]pyrimidine Derivatives Containing Sulfamoyl Moiety
Authors: Ammar Yousry A. , Aly Mohsen M. , Al‐Sehemi Abd Allah G. , Salem Mohamed A. , El‐Gaby Mohamed S. A. 
Published: May 2015

AbstractNovel 5‐aminopyrazole and pyrazolo[1,5‐a]pyrimidine derivatives have been synthesized from the readily accessible cyanoacetanilide derivative (2).