bluuebunny/crossref_metadata_2025 huggingface dataset:
Removal of Toxic As (V) Ions by Adsorption onto Alginate and Carboxymethyl Cellulose Beads
Authors: Tiwari Alka , Dewangan Tulika , Bajpai A. K.
Published: May 2015

The removal of arsenic ions from dilute aqueous solutions using biopolymeric beads of crosslinked sodium alginate and carboxymethyl cellulose (CMC) as the adsorbent is reported in this paper. The biopolymeric alginate and carboxymethyl cellulose beads were prepared and characterized by FTIR spectra. On the surfaces of the prepared beads were performed static and dynamic adsorption studies of arsenic ions at fixed pH and ionic strength of the aqueous metal ion solutions. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. The dynamic nature of adsorption was quantified in terms of several kinetic constants such as rate constant for adsorption (k1) and Lagergreen rate constant (Kad).

The influence of various experimental parameters such as solid to liquid ratio, pH, temperature, presence of salts and chemical composition of biopolymeric beads were investigated on the adsorption of arsenic ions.
Multi‐Channel Piezoelectric Quartz Crystal Sensor with Principal Component Analysis and Back‐Propagation Neural Network for Organic Pollutants from Petrochemical Plants
Authors: Chen Chiao‐Chen , Shih Jeng‐Shong
Published: May 2015

A multi‐channel piezoelectric quartz crystal gas sensor comprising arrays coated with various organic materials and a home‐made computer interface for data processing were prepared and employed to detect six kinds of common organic pollutants from petrochemical plants including benzene, styrene, chloroform, octane, hexene and hexyne. The principal component analysis (PCA) method was employed to select six kinds of appropriate coating materials for these organic pollutants from 22 adsorbents onto piezoelectric crystals. After performing a PCA assay, six representative coating materials, namely Polyisobutylene, Poly(dimethylsiloxane) (SE30), 4‐tert‐Butylcalix[6]arene, Cholesteryl chloroformate, C60‐Polyphenyl acetylene (C60‐PPA) and Ag(I)/cryptand‐2,2/Ethylene diamine/NH3/Polyvinyl chloride were selected. Moreover, effects of coating load of adsorbents and concentration of pollutants were also investigated. Three kinds of recognition techniques including 2D PCA score map, radar plot and back‐propagation neural network (BPN) were employed for qualitative analysis of these organic pollutants, and a quantitative analysis method could be established by creating calibration curves for each organic pollutant. This homemade multi‐channel piezoelectric quartz crystal gas sensor showed a good detection limit of 0.068‐1.127 mg/L for these organic pollutants. The multi‐channel piezoelectric gas sensor exhibited good reproducibility with a relative standard deviation (RSD) of 1.1‐9.6%. Furthermore, this multi‐channel piezoelectric crystal detection system with BPN recognition technique was also utilized to successfully distinguish and identify each component of the mixture of organic gas samples. Multivariate linear regression (MLR) analysis was employed to quantitatively compute the concentration of species in the organic mixtures.
Direct Electron Transfer of Hemoglobin on a Carbon Ionic Liquid Electrode with TiO2 Nanopatricle as Enhancer
Authors: Sun Wei , Li Xiao‐Qing , Jiao Kui
Published: May 2015

Room temperature ionic liquids (RTILs) N‐butylpyridinium hexafluorophosphate (BPPF6) modified carbon paste electrode (CILE) was fabricated and applied to adsorb the hemoglobin (Hb) and TiO2 nanoparticles on the electrode surface step by step to form a Hb modified electrode noted as TiO2/Hb/CILE. UV‐Vis and FT‐IR spectra showed that Hb in the film retained its native conformations. Cyclic voltammetric experiments indicated that a pair of well‐defined quasi‐reversible redox peaks appeared with the formal potential (E0′) located at −0.251 V (vs. SCE) at pH 7.0 phosphate buffer solution (PBS), which was the characteristic of heme Fe(III)/Fe(II) redox couples. Electrochemical parameters of the Hb in the film such as the electron transfer coefficient (α), the electron transfer number (n) and the standard electron transfer rate constant (ks) were estimated as 0.469, 0.87 and 0.635 s−1, respectively.
Simultaneous Determination of Cd(II), Cu(II), Pb(II) and Zn(II) in Human Plasma by Potentiometric Stripping Analysis
Authors: Wang Shu‐Jie , Zheng Hao , Ye Bao‐Xian
Published: May 2015

In this paper, Potentiometric Stripping Analysis (PSA) was simultaneously used to determine the concentrations of trace metals (Zn, Cd, Pb and Cu) in human plasma. The metal ions were concentrated as their amalgams on the glassy carbon surface of a working electrode that was previously coated with a thin mercury film and then stripped by a suitable oxidant. The selection of the experimental conditions was made by using the experimental‐designed methodology. The optimum conditions of the method includes a 0.2 M HAc‐NaAc buffer mixture (pH 4.5) as supporting electrolyte, and an electrolysis potential of‐1220 mV. The limits of detection (LOD) were obtained 1 μg L−1 for Zn(II) and Pb(II), 0.5 μg L−1 for Cu(II) and 2 μg L−1 for Cd(II) in the studied medium. The good recoveries were obtained for the analysis in human plasma. The method was applied to blood samples, using the method of standard additions and the results were compared with Inductively Coupled Plasma‐Atomic Emission Spectrometry (ICP‐AES) as reference method. Furthermore, a simple digestion protocol of samples is investigated compared to the conventional digestion method.
QSPR Study of the Distribution Coefficient Property for Hydantoin and 5‐Arylidene Derivatives. A Genetic Algorithm Application for the Variable Selection in the MLR and PLS Methods
Authors: Riahi Siavash , Pourbasheer Eslam , Ganjali Mohammad Reza , Norouzi Parviz , Moghaddam Ali Zeraatkar
Published: May 2015

A quantitative structure‐property relationship (QSPR) analysis has been performed on the 5‐arylidene derivatives of hydantoin. Modeling the distribution coefficient property of these compounds as a function of the theoretically derived descriptors was established by multiple linear regressions (MLR) and partial least squares (PLS) regression. The genetic algorithm (GA) was used for the selection of variables, which resulted in the best‐fitted models. After the selection of the variables, the MLR and PLS methods were applied with a leave‐one‐out cross validation, for building the regression models. The predictive quality of the QSPR models was tested for an external prediction set of 9 compounds randomly chosen among 48 compounds. The PLS regression method was applied to model the structure‐distribution coefficient relationship more accurately. This is, to the best of our knowledge, the first report of a QSPR study with distribution coefficient (log D65, octanol/water) relationships. However, the results surprisingly demonstrated almost identical qualities for the MLR and PLS modelings, according to the squared regression coefficients R2, which were 0.975 and 0.976 for MLR and PLS, respectively.
Synthesis of α,α′‐Bis(Substituted Benzylidene)Cycloalkanones Catalyzed by Amino‐Functionalized Ionic Liquid
Authors: Kang Li‐Qin , Song Gong‐Hua , Wang Jia‐Yi , Wei Bang‐Guo
Published: May 2015

Condensation of aromatic aldehydes with cyclopentanone and cyclohexanone using amino‐functionalized ionic liquid, 1‐aminoethyl‐3‐methyl tetrafluoroborate as solvent and catalyst was successfully performed for preparation of α,α′‐bis(substituted benzylidene)cycloalkanones. The catalyst can be recovered and reused for at least three times without apparently lose of activity. The process is simple, environmentally benign and proceeds in excellent yields.
Anticancer Drug Modified GCFE, for the Study of Its In‐Vivo Interaction Mechanism
Authors: Tiwari Sweety , Pitre Krishna Sadashiv
Published: May 2015

An anticancer drug (Adriamycin) modified Glassy Carbon Fiber Electrode (GCFE) has been prepared to study its interaction with ds‐DNA. The redox reaction of Adriamycin molecules at the chemically modified GCFE helps in understanding the in‐vivo mechanism of action of this anti cancer drug.

The modified electrode has been fabricated by the adsorption of Adriamycin on GCFE surface. The results of Differential Pulse Voltammetric (DPV) analysis in acetate buffer of pH 4.5 ± 0.1, showed that the interaction between DNA guanine and adenine bases and electrode surface, is easily detected. A suitable mechanism for the oxidation and reduction of Adriamycin in‐situ intercalated in ds‐DNA immobilized on to the GCFE surface has been explained. The drug‐DNA complex formation at GCFE surface has also been studied.

The prepared modified electrode is of utmost relevance because the mechanism of interaction of DNA‐Adriamycin at charged interfaces is parallel to the in‐vivo DNA‐Adriamycin complex reaction, where the nucleic acid is in close contact with charged phospholipid membranes and proteins. The interaction studies of Adriamycin at modified GCFE using DPV method help in understanding the DNA‐Adriamycin reaction mechanism.
A Facile Synthesis of 2,2,4‐Trisubstituted‐1,2‐Dihydroquinolines Catalyzed by Zinc Triflate under Solvent‐Free Conditions
Authors: Kundu Dhiman , Kundu Shrishnu Kumar , Majee Adinath , Hajra Alakananda
Published: May 2015

An efficient process has been developed for the synthesis of 2,2,4‐trisubstituted‐1,2‐dihydroquinolines in good yields through a simple one‐pot condensation between anilines and ketones in the presence of zinc triflate as a catalyst at room temperature under solvent‐free conditions.
A Mixed Solvothermal Route to Synthesis of Dice‐Like PbS
Authors: Zhang X. H. , Jia C. , Chen Y. Q. , Su Y. , Zhou H. Y.
Published: May 2015

The authors developed a simple solvothermal route to synthesis of PbS nanocrystals in the mild binary mixed solvent made of diethylenetriamine (DETA) and water. Two kinds of PbS nanostructures (dice‐like and cubic) have been successfully synthesized in the binary mixed solvothermal system at 150 °C by changing the sulfur source. The products were characterized by X‐ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The results show that the as‐prepared dice‐like PbS crystals have a hole on each of their faces. To elucidate the relationship between reaction systems and the morphologies of the final products, the authors also investigated the crystal growth by using different sulfur source. Based on the experimental results, the possible growth mechanism of the dice‐like PbS crystals was proposed.
Enhanced Removal of Cu(II) and Pb(II) from Aqueous Solutions by Pretreated Biomass of Fusarium Solani
Authors: Bhatti Haq Nawaz , Samin Ghufrana , Hanif Muhammad Asif
Published: May 2015

This study investigated the feasibility of Fusarium solani biomass as a biosorbent for Cu(II) and Pb(II) removal from aqueous solutions. Batch sorption experiments were carried out for Cu(II) and Pb(II) to quantify the sorption kinetics, pH, biosorbent dose and pretreatment of F. solani biomass. Biomass metal uptake clearly competed with protons present in the aqueous medium, making pH an important variable in the process. The maximum biosorption by F. solani biomass was obtained with solutions having pH 5 for both metal ions. An enhanced Cu(II) removal (96.53%) was observed for aluminum hydroxide pretreated biomass. Maximum Pb(II) removal (95.48%) was observed with native biomass. Time dependence experiments for the metal ions uptake showed that adsorption equilibrium reached almost 240 min after metal addition. The kinetic studies showed that the biosorption process followed the pseudo second‐order rate model for Cu(II) and Pb(II). The equilibrium data fitted well to the Langmiur isotherm model.
Facile Synthesis of 3(2H)‐Pyridazinones and 2(3H)‐Furanones of Anticipated Biological Activities
Authors: Morsy J. M.
Published: May 2015

3‐Aroyl‐2‐arylpropionic acids 2a‐e were utilized to synthesize 3(2H)‐pyridazinones 3a‐e and 2(3H)‐furanones 6 through reaction with hydrazine hydrate and freshly distilled acetic anhydride, respectively, in the hope of obtaining new 3(2H)‐pyridazinones with no ulcerogenic side effect or with negligible general side effects as those currently used NSAIDS as well as biologically active 2(3H)‐furanones.
FT‐IR Studies of Plasticization of Propylene Carbonate and Ethylene Carbonate in PEO‐NaSCN Polymer Electrolytes
Authors: Zhang Hu‐Cheng , Wang Jian‐Ji
Published: May 2015

The FT‐IR spectra of poly(ethylene oxide) (PEO)‐based gel polymer electrolytes (GPEs), PEO‐NaSCN‐propylene carbonate (PC) and PEO‐NaSCN‐ethylene carbonate (EC), were measured at room temperature. Along with the FT‐IR spectra of NaSCN‐PC, PEO‐PC, and PEO‐EC, the interactions in the GPEs and the plasticizations of PC and EC are revealed. It is shown that the coordination of ether oxygen in PEO with NaSCN is the preferential solvation, whereas the interactions of PC and EC with NaSCN are relatively weak in the GPEs. However, both PC and EC play an important role in inhibiting the formation of crystalline complexes and high ionic aggregations, in addition to the ability of transformation of PEO from crystal to amorphism. It is further observed that EC exhibits the stronger ability to transform PEO crystalline into amorphism than PC when the plasticizer content in PEO is more than 25%, and also the far stronger ability to decompose the crystalline complexes, in particular, in polymer electrolytes with high salt content.
Synthesis and Structural Characterisation of Derivatives of Tricyclo[5.2.1.02,6]Dec‐8‐Ene‐3,5‐Dione with an Expected Antimicrobial Activity
Authors: Struga Marta , Krawiecka Mariola , Kossakowski Jerzy , Stefańska Joanna , Miroslaw Barbara , Koziol Anna E.
Published: May 2015

Anhydrides, imides, N‐ethylimides, N‐hydroxyimides and N‐aminoimides of 1,4,5,6‐tetramethyl‐bicyclo[5.2.1.02,6]hept‐5‐ene‐2,3‐dicarboxylic acid, 1,4,5,6,7‐pentamethyl‐bicyclo[5.2.1.02,6]hept‐5‐ene‐2,3‐dicarboxylic acid and 7‐ethyl‐1,4,5,6‐tetramethyl‐bicyclo[5.2.1.02,6]hept‐5‐ene‐2,3‐dicarboxylic acid were obtained. Antimicrobial activity of the newly obtained derivatives was tested against selected Gram‐positive and Gram‐negative bacteria and fungi of the Candida species. The structures of obtained compounds and their antimicrobial activity were compared. Structure of 1b, 2b and 1e were determined by an X‐ray analysis.
Fe3+‐Montmorillonite: An Efficient Solid Catalyst for One‐Pot Synthesis of Decahydroacridine Derivatives
Authors: Luo Haitang , Kang Yuru , Nie Hongyun , Yang Liming
Published: May 2015

Fe3+‐montmorillonite was used as a solid acidic catalyst for the synthesis of decahydroacridine derivatives through the condensation of aromatic aldehydes, dimedone and aniline in ethanol. The influence of reaction time, reaction temperature, and the amount of catalyst were studied. All the compounds were characterized by IR, Mp, 1H NMR and 13C NMR analysis.
Sesquiterpenoids‐Related Metabolites from the Soft Coral Sinularia sp.
Authors: Su Jui‐Hsin , Hsieh Chi‐Hua , Lo Ching‐Li , Huang Chiung‐Yao , Dai Chang‐Feng , Kuo Yao‐Haur , Sheu Jyh‐Horng
Published: May 2015

Two new sesquiterpenoids, sinularioperoxide E (1), ethyl 5‐[(2′S,5′E)‐2′, 6′‐dimethylocta‐5′,7′‐dienyl]furan‐3‐carboxylate (3), and a new C11 terpenoid‐related carboxylic acid, (3S,6E)‐3,7‐dimethyl‐nona‐6,8‐dienoic acid (2) were isolated from a Formosan soft coral Sinularia sp. The structures of 1‐3 were elucidated on the basis of extensive spectroscopic analyses and by comparison of the spectral data with those of the related metabolites.
Substitute Effect on the Structure, Stability of Valence Isomers and Aromaticity of 1‐H‐Boratabenzene
Authors: Ghiasi Reza , Yadegari Neda
Published: May 2015

Density functional theory (B3LYP) calculations were performed on the Me and F substituted valence isomeric forms of 1‐H‐boratabenzene. The calculations revealed that the planar benzene analog is the lowest energy isomer. Its aromaticity is analyzed in the light of the nucleus‐independent chemical shift (NICS) and shows that aromaticity increases in F substituted, but decreases in Me substituted. These calculations indicate substitution of BH with BMe and BF doesn't cause significant variation in bond length.
Synthesis and In Vivo Anticonvulsant Screening of Coumarin Incorporated Schiff Bases of 1,3,4‐Oxadiazoles
Authors: Siddiqui Nadeem , Bhat Mashooq A. , Khan Suroor A. , Ahsan Waquar , Alam M. Shamsher
Published: May 2015

A series of coumarin incorporated Schiff bases of 1,3,4‐oxadiazoles (1‐18) was synthesized. The structures of the synthesized compounds were confirmed on the basis of spectral data and elemental analysis. The anticonvulsant and neurotoxicity was studied by maximal electroshock seizure (MES) and rotorod method, respectively. A majority of the compounds were active in MES test. All the compounds were less neurotoxic than the standard drug phenytoin.
Study on Determination of Triterpenoids in Chaenomeles by High Performance Liquid Chromatography and Sample Preparation with Matrix Solid Phase Dispersion
Authors: Li Yin‐Ke , Fan Peng , Xu Yi‐Ran , Huang Yun , Hu Qiu‐Fen
Published: May 2015

A new method for the simultaneous determination of the major triterpenoids in Chaenomeles (Chinese medicinal herb) by high performance liquid chromatography (HPLC) and sample preparation with matrix solid phase dispersion (MSPD) was developed. A 0.1 g of sample was placed into an agate mortar and gently blended with 0.4 g silica gel to obtain a homogeneous mixture. This mixture was introduced into a Teflon cartridge, and the triterpenoids fraction was eluted from the cartridge with dichloromethane‐acetone (85:15). The residue was dissolved with methanol after the evaporation of the solvent (dichloromethane and acetone). The triterpenoids were separated on a ZORBAX Stable Bound (4.6 mm × 100 mm, 1.8 μm) C18 column by gradient elution with acetonitrile and water as the mobile phase and detected with evaporative light scattering detection. This method provides good reproducibility and sensitivity for the quantification of seven major triterpenoids, namely erythodiol, betulin, acetyl ursolic acid, ursolic acid, oleanolic acid, betulinic acid, pomolic acid, respectively. The relative standard derivations of overall intra‐day variations were less than 2.0%, and the relative standard derivations of inter‐day variations were less than 2.5%. The standard recoveries (three different concentrations of markers: 0.1, 0.5 and 2.0 mg) ranged from 97‐103%. The results demonstrate that this method is simple, sensitive, selective, and suitable for the quality control of this commonly used Chinese medicinal herb.
Oxidative Aromatization of 1,3,5‐Trisubstituted 4,5‐Dihydro‐1H‐Pyrazoles Efficiently by Tetrabromine‐1,3,5,7‐Tetrazatricyclo[3.3.1.13,7]Decane Complex, Br4‐Tatcd, as a Novel Reagent both Under Microwave Irradiation and at Room Temperature
Authors: Azarifar Davood , Khosravi Kaveh
Published: May 2015

Oxidation of 1,3,5‐trisubstituted 4,5‐dihydro‐1H‐pyrazoles to the corresponding pyrazoles has been achieved by utilizing tetrabromine‐1,3,5,7‐tetrazatricyclo[3.3.1.13,7]decane complex, Br4‐TATCD, in glacial acetic acid under microwave irradiation and conventional thermal condition at room temperature with excellent yields.
Synthesis of a Novel Type of Phosphoramidate Derivatives of 2‐Arylquinolone
Authors: Yuan Jin‐Wei , Chen Xiao‐Lan , Qu Ling‐Bo , Qu Zhi‐Bo , Zhou Ya‐Dong , Zhao Yu‐Fen
Published: May 2015

A novel type of phosphoramidate derivatives of 2‐arylquinolone were synthesized through a facile phosphorylated reaction for the first time. The structure of these compounds was elucidated by IR, HR MS, NMR and X‐ray. Synthesis and structural characterization of the titled compounds was discussed.
A 3D‐QSAR Study of Celebrex‐Based Pdk1 Inhibitors Using Comfa Method
Authors: Wang Wen‐Hung , Jena N. R. , Wang Yi‐Ching , Sun Ying‐Chieh
Published: May 2015

A 3D‐QSAR study of celebrex‐based compounds of PDK1 inhibitors using comparative molecular field analysis (CoMFA) was carried out. The structures of the compounds were obtained using quantum chemistry calculation. CoMFA calculations for a number of grouped subsets of compounds gave q2 values of correlation in the range from 0 to 0.8. The low q2 values should be mainly due to the narrow span of biological activity. Calculations for several subsets of 11–13 compounds gave high q2 values, with 0.5–0.8. Factors affecting the results of the calculations are discussed. Calculated results with high q2 values suggest that further chemical modifications of the compounds could lead to enhanced activity and could be an aid in the design of celebrex‐based cancer drugs.
Gelation of a Highly Fluorescent Urea‐Containing Triarylmelamine Derivative: 2,4,6‐Tris(p‐N′‐Octadecylureido‐Anilino)Triazine in Organic Solvents
Authors: Lu Cheng‐Chi , Su Shuenn‐Kung
Published: May 2015

A new gelator of urea‐containing triazine derivatives was synthesized and tested in order to explore the gelation potential in different organic solvents. This compound has been found to form organogels with a variety of organic solvents such as decalin and other solvents. The resulting thermo‐reversible gel was characterized by using the dropping ball method and a number of other instruments. The melting temperature of the gel increased with the gel concentration. The intermolecular hydrogen bonding of gelation was demonstrated through an FT‐IR spectrometer. UV‐Vis and fluorescence analysis showed that the gel displayed various optical effects in different organic solvents. The blue fluorescence of the gel in decalin and the quenched effect of gel in CHCl3 were displayed, respectively. Morphological features in decalin and CHCl3 were studied by applying atomic force microscopy (AFM), and the morphological features demonstrated that there were different aggregations in different solvents. In conductivity electrolyte experiments, the organogel electrolytes indicated high conductivity (σ) comparable to the corresponding NaClO4/THF solution. The conductivity of gel electrolytes was increased with electrolyte salt.
Electropolymerization of Methylene Blue on Carbon Ionic Liquid Electrode and Its Electrocatalysis to 3,4‐Dihydroxybenzoic Acid
Authors: Zhao Rui‐Jun , Jiang Qiang , Sun Wei , Jiao Kui
Published: May 2015

In this paper an ionic liquid modified carbon paste electrode (CILE) was prepared and methylene blue (MB) was electropolymerized on the CILE by using the cyclic voltammetric technique in the potential range from −1.0 V to 0.8 V (vs. SCE). A stable polymer film was obtained and exhibited a pair of redox peaks. The morphology and characteristics of poly(methylene blue) (PMB) film was studied by the techniques such as scanning electron microscopy and electrochemical impedance spectroscopy. This PMB modified CILE (PMB/CILE) showed excellent electrocatalytic response to 3,4‐dihydroxybenzoic acid with the increase of the electrochemical responses. The oxidation peak current had a linear relationship with 3,4‐dihydroxybenzoic acid concentration in the range of 5.0 × 10−4 ∼ 3.0 × 10−2 mol L−1 and the detection limit was 1.72 × 10−4 Mol L−1 (3 σ).
Synthesis of Novel 3‐Acetyl‐2‐Aryl‐5‐(3‐Aryl‐1‐Phenyl‐Pyrazol‐4‐yl)‐2,3‐Dihydro‐1,3,4‐Oxadiazoles
Authors: Li Cun‐Kui , Ma Yu‐Jie , Cao Ling‐Hua
Published: May 2015

A series of novel pyrazolyl‐substituted 1,3,4‐oxadiazole derivatives (4a‐4o) were prepared by cyclization of the intermediate N′‐((3‐aryl‐l‐phenyl‐pyrazol‐4‐yl)methylene)arylhydrazide with acetic anhydride. The structures of the new compounds were confirmed by IR, 1H NMR, MS and elemental analysis. Furthermore, preliminary bioassay of some of the title compounds indicated that they exhibited moderate inhibition against HIV‐1 PR.
Synthesis of Spiro‐Heterocycles with the Thiazolidinone Moiety from Nitrilimines
Authors: Dalloul Hany M.
Published: May 2015

The 2‐phenylimino‐1,3‐thiazolidin‐4‐one 2 was obtained by thermal cyclization of 4‐amino‐5‐phen‐yl‐3, 5‐thiaaza‐4‐pentenoic acid 1 using DCC as dehydration agent. Treatment of 2‐phenylimino‐1,3‐thiazolidin‐4‐one 2 with various hydrazonoyl halides 3 (nitrilimines 4 precursor) yielded 6‐aryl‐9‐phenyl‐8‐substituted‐1,4,6,7,9‐thiatetrazaspiro‐[4.4]non‐7‐en‐3‐ones 5a‐1. Both analytical and spectroscopic data of all the synthesized compounds are in full agreement with the proposed structures.
Synthesis of Arylhydrazines by Reaction of Arylbromides with DEAD via Sonochemical Barbier Reaction
Authors: Lee Adam Shih‐Yuan , Chung Ching‐Hui , Chu Shu‐Fang , Chang Yu‐Ting
Published: May 2015

A series of arylhydrazines was synthesized from the reaction mixture of Mg powder, 1,2‐dibromoethane, aryl bromide and DEAD (diethyl azodicarboxylate) in THF under ultrasound. This sonochemical Barbier reaction provides an efficient and inexpensive preparation method for synthesis of arylhydrazines.
Highly Efficient Method for Synthesis of Bis(Indolyl)Methanes Catalyzed by FeCl3−based Ionic Liquid
Authors: Veisi Hojat , Hemmati Saba , Veisi Hamed
Published: May 2015

A simple and highly efficient green protocol for synthesis of bis(indolyl)methanes was carried out by the reaction of indole with aldehydes and ketones in the presence of FeCl3−based ionic liquid. These liquids serve as efficient media as well as Lewis acid catalysts.
Synthesis and Characterization of Novel Stilbene Derivatives with 1,3,4‐Oxadiazole Unit
Authors: He Dao‐Hang , Zhu Yong‐Chuang , Yang Zhuo‐Ru , Hu Ai‐Xi
Published: May 2015

Four novel stilbene derivatives containing 1,3,4‐oxadiazole unit have been synthesized in four steps with overall yields (27∼35%). The synthetic route involved one‐step installation of 2,5‐di‐p‐tolyl‐1,3,4‐oxadiazol via the direct coupling of p‐toluic acid with hydrazine hydrate promoted by PPA, benzylic bromination, conventional phosphonate formation, and Wittig‐Horner olefination.
Preparation and Antibacterial Effect of Bamboo Charcoal/Ag on Staphylococcus Aureus and Pseudomonas Aeruginosa
Authors: Yang Fu‐Chu , Wu Kuo‐Hui , Lin Wen‐Po , Hu Ming‐Kuan , Sheu Tsung‐Sheng , Horng Deng‐Nan
Published: May 2015

Bamboo charcoal supporting silver (BC/Ag) was prepared by activation and chemical reduction. The BC/Ag composites were characterized by silver particle size and distribution, silver ion (Ag+) release and antibacterial properties. Scanning and transmission electron microscopy (SEM and TEM) showed that the Ag particles were distributed uniformly on the BC matrix. The Ag particle size was found to be less than 150 nm based on TEM. The Ag+ release increased initially which was followed by a marginal increase between the 8th and 24th hour. Composites contained higher amounts of silver exhibited a further rise in Ag+ release from the 24‐hours of storage in water. The antibacterial effects of the BC/Ag composite powders against Pseudomonas aeruginosa and Staphylococcus aureus were assessed from the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) method, and an excellent antibacterial performance was discovered.
An Efficient Synthesis of 14‐Aryl or Alkyl‐14H‐Dibenzo[a. j]Xanthenes Using Reusable HBF4‐SiO2 Catalyst Under Thermal and Solvent‐Free Conditions
Authors: Fu Gui‐Yun , Huang Yi‐Xiang , Chen Xiao‐Gang , Liu Xiao‐Ling
Published: May 2015

A simple and convenient procedure for the synthesis of 14‐aryl or alkyl‐14H‐dibenzo[a. j]xanthene derivatives is described through a one‐pot condensation of β‐naphthol with various aryl or alkyl aldehydes in the presence of HBF4‐SiO2 as the catalyst under thermal and solvent‐free conditions.
Synthesis of Novel Guanidinogalactosides
Authors: Yang Jin‐Feng , Cao Ling‐Hua
Published: May 2015

This paper involves the preparation of thioureas, which couple with per‐O‐acetylated galactosyl isothiocyanate 1 and 2‐aminobenzothiazole 2 to give incorporating galactosylthiourea derivatives 3. Nucleophilic addition of active primary amine to 3 in the presence of HgCl2 afforded the per‐O‐acetylated guanidinogalactoside 4a‐4d, 5a‐5d, 6a‐6d, 7a‐7d in good yield. These adducts were subjected to deacetylation in MeOH/NaOMe and furnished the corresponding unprotected guanidinogalactosides 8a‐8d, 9a‐9d, 10a‐10d, 11a‐11d. The structures of all newly synthesized compounds were established by IR, 1H NMR, MS and elemental analysis.
Brönsted Acidic Ionic Liquid as an Efficient Catalyst for Acetylation of Alcohols and Phenols
Authors: Hajipour Abdol R. , Khazdooz Leila , Ruoho Arnold E.
Published: May 2015

A novel Brönsted acidic room temperature ionic liquid (1‐H‐3‐methyl‐imidazolium bisulfate) is found to catalyze efficiently the acetylation of a wide rang of alcohols as well as phenols with acetic anhydride in good to excellent yields at 50°C under solvent‐free conditions. Products are easily isolated by extraction with ether and the protocol is mild and green, compared to the existing method based on toxic solvents.
Synthesis and Structure of Novel Thieno[2, 3‐d]Pyrimidine Derivatives Containing 1, 3, 4‐Oxadiazole Moiety
Authors: Ho Yuh‐Wen , Suen Maw‐Cherng
Published: May 2015

The reaction of 5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2, 3‐d]pyrimidine carbohydrazide 5 with CS2 in the presence of pyridine afforded the 6‐(2, 3‐dihydro‐2‐mercapto‐1, 3, 4‐oxadiazol‐5‐yl)‐4‐methyl‐5‐(1‐pyrrolyl)‐2‐phenylthieno[2, 3‐d]pyrimidine 6, which reacted with methyl iodide in the presence of sodium methoxide to yield the 6‐(2‐methylthio‐1, 3, 4‐oxadiazol‐5‐yl)‐4‐methyl‐5‐(1‐pyrrolyl)‐2‐phenyl‐thieno[2, 3‐d]pyrimidine 7. The 6‐(2‐substituted‐1, 3, 4‐oxadiazol‐5‐yl)‐2‐phenylthieno[2, 3‐d]pyrimidine derivatives 9, 11 and 13 were obtained by the condensation of 6‐(2‐methylthio‐1, 3, 4‐oxadiazol‐5‐yl)‐2‐phenylthieno[2, 3‐d]pyrimidine 7 with appropriate secondary amines. The structure of the new compounds was substantiated from their IR, UV‐vis spectroscopy, 1H NMR, mass spectra, elemental analysis and X‐ray crystal analysis.
Surface Modifications and Optoelectronic Characterization of TiO2‐Nanoparticles: Design of New Photo‐Electronic Materials
Authors: Yoon Min‐Joong
Published: May 2015

TiO2 nanoparticles are of great current interest for applications in photo‐electronic materials including light‐energy conversion, artificial photosynthetic systems as well as photocatalysis. The success of these applications relies on the exciton recombination dynamics and visible‐light sensitivity of the TiO2 nanomaterials. Thus, in order to develop the highly efficient photo‐electronic materials absorbing visible light, different low dimensional TiO2 nanostructures such as nanodiscs, nanofibers and nanochains were synthesized, and thereafter their surfaces were modified by incorporating with Sn‐porphyrins and heteropoly acid. The optoelectronic properties of the surface‐modified nanomaterials were investigated with regard to the optical properties and the surface exciton dynamics by using both steady‐state and ultrafast time‐resolved laser spectroscopic techniques including single nanoparticle photoluminescence technique. These results were correlated with the photo‐electronic properties including photocatalytic activities and solar cell efficiencies, indicating that the electron transfer mechanism in the modified nanostructures may be similar to the “Z‐scheme” of the plant photosynthetic system so that both photocatalytic activity and solar cell efficiencies were synergistically enhanced by using two color illumination.
Association Equilibrium of Methylene Blue by Spectral Titration and Chemometrics Analysis: A Thermodynamic Study
Authors: Ghasemi Jahan B. , Miladi M.
Published: May 2015

The monomer‐dimer equilibrium of methylene blue (MB, Scheme I) has been investigated by means of UV‐Visible spectroscopy in aqueous solutions. The self aggregation of MB in water has been investigated by recording absorption spectra in the wavelength range of 450–750 nm, and in different ionic strengths using concentrated KCl solutions in the temperature range of 20–90°C. Chemometrics analysis of the spectral data gave a dimerization constant, individual spectra of the monomer and dimer forms of the dye molecule. The quantitative analysis of the data of the undefined mixture was carried out by simultaneous resolution of the overlapping spectral bands in the whole set of absorption spectra. The dimerization constants of MB determined by mathematical deconvolution of the thermometric spectral titration data show dependency on temperature variations. The concentration range of MB was 6.00 × 10−5‐3.00 × 10−4 M. Utilizing the van't Hoff relation, which describes the dependence of the equilibrium constant on temperature, the thermodynamics parameters ΔH° and ΔS° of the aggregation process were determined. The compensation effect was verified by the thermodynamics results of the dimerization process of the dye.
Preparation of NiO/MWNTs Nanocomposites by a Simple Chemical Precipitation Method
Authors: Liao Xiao‐Ning , Hu Chang‐Yuan , Wang Qiao‐Ling , Li Feng‐Yi
Published: May 2015

NiO/MWNTs nanocomposites have been prepared by a simple and efficient chemical precipitation method with the aid of sodium dodecyl sulfate (SDS). Hybrid materials were characterized by XRD, TEM, EDX, Zeta potential and FT‐IR techniques. Experimental results show that NiO nanoparticles with the size of less than 9 nm are well‐dispersed on the outside of MWNTs functionalized with SDS. Hydrogenated NiO/MWNTs hybrid materials exhibit good catalytic performance in the benzene hydrogenation reaction.
Three‐Component One‐Pot Synthesis of Indeno[2′,1′:5,6]Pyrido[2,3‐d]Pyrazole Derivatives in Aqueous Media
Authors: Shi Da‐Qing , Shi Jing‐Wen , Yao Hao
Published: May 2015

A series of indeno[2′,1′:5,6]pyrido[2,3‐d]pyrazoles was synthesized by the three‐component reaction of aldehyde, 5‐amino‐3‐methyl‐1‐phenylpyrazole and 1,3‐indenedione in the presence of SDS in aqueous media. The structures were characterized by IR, 1H NMR, high resolution mass spectra and were further confirmed by X‐ray diffraction analysis.
Metal Trifluoromethanesulfonate‐Catalyzed Regioselective Reductive Ring Opening of Benzylidene Acetals
Authors: Shie Chi‐Rung , Tzeng Zheng‐Hao , Wang Cheng‐Chung , Hung Shang‐Cheng
Published: May 2015

A systematic study of various metal trifluoromethanesulfonates as efficient catalysts in the regioselective reductive ring opening of benzylidene acetals is described, including the effects of solvents, reducing agents, and temperature. These catalysts are found to be effective in cleaving the 4,6‐O‐acetal rings of hexopyranosides at either O4 or O6, respectively. When used in conjunction with a 1 M solution of BH3·THF in THF without extra addition of any solvent, it affects the ring fission at the O6 position to generate the corresponding primary alcohols, whereas O4‐opening takes place in acetonitrile in the presence of dimethylethylsilane as the reductant leading to the secondary hydroxyl derivatives in high selectivity and yields. These methodologies can be applied to a wide range of substrates containing various functional groups.
Transition Metal Complexes of N‐(4,6‐Dimethoxypyrimidin‐2‐Ylcarbamothioyl)Benzamide: Design, Synthesis and Herbicidal Activity
Authors: Wu Ai‐Bin , Duan Li‐Ping
Published: May 2015

Transition metal (Cu(II), Zn(II), Co(II)) complexes of N‐(4,6‐dimethoxypyrimidin‐2‐ylcarbamothioyl)benzamide were prepared. The structures of all the newly synthesized complexes were identified by elemental analyses, IR, 1H NMR, XPS, MS and TG. Their herbicidal activities were evaluated against a variety of weeds. The preliminary results showed that the target complexes had moderate biological activities against both broad leaf weeds and monocotyledon plants. More importantly, the complexes exhibited some improved herbicidal activities over their non‐complexed counterparts. The present work provides a novel class of transition metal‐based derivatives with potent herbicidal activities for further optimization.
Kinetic Study of the Electro‐Catalytic Oxidation of Acetaldehyde on Copper Electrode
Authors: Karim‐Nezhad Ghasem , Hasanzadeh Mohammad , Saghatforoush Lotfali , Ershad Sohrab , Shadjou Nasrin
Published: May 2015

Electrocatalytic oxidation of acetaldehyde was investigated on a copper electrode in alkaline solution. The process of oxidation involved and its kinetics were established by using cyclic voltammetry and chronoamperometry techniques as well as steady state polarization measurements. It has been found that in the course of an anodic potential sweep the electro‐oxidation of acetaldehyde follows the formation of Cu(III) and is catalysed by this species through a mediated electron transfer mechanism. A mechanism based on the electrochemical generation of Cu(III) active sites and their subsequent consumption by the acetaldehyde in question was also investigated.
A Novel Spectrophotometric Method for the Determination of Levodopa with the Detection System of Potassium Ferricyanide‐Fe(III)
Authors: Guo Li , Zhang Yan , Li Quan‐Min
Published: May 2015

In this paper, a novel method has been established to determine levodopa with the detection system of potassium ferricyanide‐Fe(III). In the presence of potassium ferricyanide, it has been demonstrated that Fe(III) is reduced to Fe(II) by levodopa at pH 4.0. In addition, the in situ formed Fe(II) reacts with potassium ferricyanide to form soluble prussian blue (KFeIII[FeII(CN)6]). Beer's law is obeyed in the range of levodopa concentrations of 0.01–4.00 μg mL−1 at the maximal absorption wavelength of 735 nm. The linear regression equation is A = 0.0082 + 0.61365 C (μg mL−1) with a correlation coefficient of 0.9996. The detection limit (3σ/k) is 9 ng mL−1, and R.S.D. is 0.73% (n = 11). Moreover, the apparent molar absorption coefficient of indirect determination of levodopa is 1.2 × 105 Lmol−1cm−1. The parameters with regard to determination are optimized, and the reaction mechanism is discussed. This method has been successfully applied to determine levodopa in pharmaceutical, serum and urine samples. Analytical results obtained with this novel assay are satisfactory.
Green Regioselective Azidolysis of Epoxides Catalyzed by Multi‐Site Phase‐Transfer Catalyst
Authors: Kiasat Ali Reza , Mirzajani Roya , Shalbaf Haji , Tabatabaei Tahereh , Fallah‐Mehrjardi Mehdi
Published: May 2015

A facile synthesis of 1,2‐azidoalcohols from their epoxides using α,α',α”‐N‐hexakis(triethylammoniummethylene chloride)‐melamine as a multi‐site phase‐transfer catalyst in water was developed. By this eco‐friendly and highly atom‐economic method, a variety of 1,2‐azidoalcohols was obtained in high yields with excellent regioselectivity and in short reaction times. Application of this six‐site PTC in the ring opening of epoxides by cyanide, acetate and chloride anions was also studied. The catalyst can be recovered after completion of the reaction and can be recycled without affecting the catalytic property.
The Antimicrobial Activity, Mosquito Larvicidal Activity, Antioxidant Property and Tyrosinase Inhibition of Piper Betle
Authors: Row Li‐Ching Morgan , Ho Jiau‐Ching
Published: May 2015

The essential oil and methanolic and aqueous extracts of Piper betle L. were assayed for their antimicrobial activity, mosquito larvicidal activity, antioxidant property and mushroom tyrosinase inhibition. The methanolic and aquaous extracts showed strong activity against the yeasts: C. albicans, and M. pachydermatis. The crude essential oil exhibited a broad‐spectrum strong antimicrobial activity against all test organisms. The strongest activity was observed against C. albicans, followed by S. aureus and M. pachydermatis. The chemical composition of the essential oil and its fractions was analyzed by GC/MS analysis. Eugenol (36.2%), chavibetol acetate (16.9%), 4‐allylphenyl acetate (9.4%) and 4‐allylphenol (7.2%) were the main components, comprising 69.7% of the oil. The fractionation of the essential oil gave two fractions. Fraction I was rich in eugenol (71.3%) and fraction II in eugenol (46.4%), chavibetol acetate (19.4%) and 4‐allylphenyl acetate (11.8%). The essential oil exhibited the mosquito larvicidal activity with 2 h and 24 h LD50 value of 86 and 48 ppm, respectively. The methanolic extract of P. betle showed larvicidal activity with 2 h and 24 h LD50 value of 153 and 125 ppm, respectively, whereas the aqueous extract showed slight active. The individual antioxidant assays such as DPPH scavenging activity, chelating effect of ferrous ions and reducing power have been used. P. betle showed remarkable antioxidant activity in DPPH and reducing power assays. The activity observed can be attributed to the presence of the phenolic compounds. The essential oil exhibited concentration‐dependent inhibition of mushroom tyrosinase, giving an IC50 value of 126 ppm. The fraction I showed a strong inhibition of tyrosinase activity, giving an IC50 value of 115 ppm. The presence of 4‐allylphenolic components in the essential oil may play an important role in the inhibition of tyrosinase. In conclusion, the results presented here show that Piper betle essential oil could be considered as a natural antimicrobial, mosquito larvicidal, antioxidant and tyrosinase inhibition source.
Cloning and Expression of Chitinase A from Serratia Marcescens for Large‐Scale Preparation of N,N‐Diacetyl Chitobiose
Authors: Wu Yue‐Jin , Cheng Chih‐Yu , Li Yaw‐Kuen
Published: May 2015

The gene of Serratia marcescens chitinase A (chiA) was cloned by PCR. The complete gene was constructed into a pRSET vector and expressed in Escherichia coli. The recombinant enzyme was purified to > 90% homogeneity by hydrophobic interaction chromatography followed by ion‐exchange separation. Measured with an electrospray‐ionization mass spectrometer, the molecular mass of the protein was 58,607 Da, consistent with a theoretical calculation of the deduced protein without the signal peptide. The recombinant enzyme was characterized and tested for the preparation of chitobiose. In general, the recombinant Chtinase A exhibited an exo‐type catalytic activity toward colloidal chitin and released both N‐acetylglucosamine and N,N‐diacetyl chitobiose as products. After extensive testing, we produced N,N‐diacetyl chitobiose as the predominant product when the enzymatic reaction was performed in sodium acetate buffer at pH 5.5; under such conditions, an enzymatic process is established for the production of the disaccharide on a 100‐g scale.
Interactions of Human Serum Albumin with Phenothiazine Drugs: Insights from Fluorescence Spectroscopic Studies
Authors: Bai Hai‐Xin , Liu Xiao‐Hua , Yang Fan , Yang Xiu‐Rong
Published: May 2015

This study was based on the use of fluorescence quenching and differentiation between static and dynamic quenching, as well as energy transfer for distance measurements. The interactions of human serum albumin with phenothiazine drugs, i.e. phenothiazine, chlorpromazine, perphenazine and promethazine, were studied and extrapolated important information on quenching mechanism, types of interaction force, binding‐site number and distance between Trp214 in HSA and the bound drugs. This study has great significance in methodology and understanding the protein‐drug interaction mechanism.
Synthesis, Structural Characterization and Thermal Stability of [Mn(3‐bpd)2(NCS)2(H2O)2]·2H2O (1) and {[Mn(bpe)(NCS)2(H2O)2]·(3‐bpd)·(bpe)·H2O}n (2) from One‐Pot Crystallization
Authors: Liu Chuan‐Yien , Lee Gene‐Hsiang , Wang Hsin‐Ta
Published: May 2015

Two supramolecular architectures, [Mn(3‐bpd)2(NCS)2(H2O)2]·2H2O (1) and {[Mn(bpe)(NCS)2(H2O)2]·(3‐bpd)·(bpe)·H2O}n (2) [bpe = 1,2‐bis(4‐pyridyl)ethylene and 3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene] have been synthesized and characterized by spectroscopic, elemental and single crystal X‐ray diffraction analyses. Compound 1 crystallizes in the monoclinic system, space group P21/c, with chemical formula C26H28Mn N10O4S2, a = 9.1360(6), b = 9.7490(6), c = 17.776(1) Å, β = 93.212(1)°, and Z = 2 while compound 2 crystallizes in the orthorhombic system, space group P212121, with chemical formula C38H36Mn1N10O3S2, a = 14.1902(6), b = 15.4569(7), c = 18.2838(8) Å, α = β = γ = 90°, and Z = 4. Structural determination reveals that the coordination geometry at Mn(II) in compound 1 or 2 is a distorted octahedral which consists of two nitrogen donors of two NCS−ligands, two oxygen donors of two water molecules, and two nitrogen donors of two 3‐bpd ligands for 1 and two dpe ligands for 2, respectively. The two 3‐bpd ligands in 1 adopt a monodentate binding mode and the dpe in 2 adopts a bismonodentate bridging mode to connect the Mn(II) ions forming a 1D chain‐like coordination polymer. Both the π‐π stacking interactions between the coordinated and the free pyridyl‐based ligands and intermolecular hydrogen bonds among the coordinated and the crystallized water molecules and the free pyridyl‐based ligands play an important role in construction of these 3D supramolecular architectures.
The Nitrogen‐Assisted Triphenylphosphine Displacement of 3‐Hydroxypyridine and 3‐Aminopyridine Ligands in Palladium(II) Complexes: Crystal Structures of [Pd(PPh3)Br]2{μ,η2‐C5H3N(OH)}2 and [Pd(PPh3)Br]2{μ,η2‐C5H3N(NH2)}2
Authors: Yih Kuang‐Hway , Wang Hsiao‐Fen , Huang Keh‐Feng , Kwan Chang‐Chi , Lee Gene‐Hsiang
Published: May 2015

Treatment of Pd(PPh3)4 with 2‐bromo‐3‐hydroxypyridine [C5H3N(OH)Br] and 3‐amino‐2‐bromopyridine [C5H3N(NH2)Br] in dichloromethane at ambient temperature cause the oxidative addition reaction to produce the palladium complex [Pd(PPh3)2{η1‐C5H3N(OH)}(Br)], 2 and [Pd(PPh3)2{η1‐C5H3N(NH2)}(Br)], 3, by substituting two triphenylphosphine ligands, respectively. In dichloromethane solution of complexes 2 and 3 at ambient temperature for 3 days, it undergo displacement of the triphenylphosphine ligand to form the dipalladium complexes [Pd(PPh3)Br]2{μ,η2‐C5H3N(OH)}2, 4 and [Pd(PPh3)Br]2{μ,η2‐C5H3N(NH2)}2, 5, in which the two 3‐hydroxypyridine and 3‐aminopyridine ligands coordinated through carbon to one metal center and bridging the other metal through nitrogen atom, respectively. Complexes 4 and 5 are characterized by X‐ray diffraction analyses.
Investigation of Electrochemical Copolymerization of 1‐Naphthylamineaniline in the Presence of Various Organic Sulfonic Acids
Authors: Massoumi Bakhshali , Aghili Hakimeh , Entezami Aliakbar
Published: May 2015

The electrochemical and electro activity properties of poly(aniline‐co‐1‐naphthylamine) thin films have been investigated in the presence of various organic sulfonic acids. Homo and copolymer thin films are synthesized electrochemically, under cyclic voltammetric conditions in aqueous solution of organic sulfonic acids (1 M), viz p‐toluene‐sulfonic acid (P‐TSA), methane‐sulfonic acid (MSA), 5‐sulfosalicylic acid (5‐SSA), camphor‐sulfonic acid (CSA) and dodecylbenzene‐sulfonic acid (DBSA) (0.25 M) on glass carbon (GC) electrode at room temperature. The cyclic voltammograms (CVs) show that the current densities are strongly influenced by the size and acidity of the organic acids which are present in electrolyte. Electocopolymerization was carried out at different ratios of NPA to ANI (0.07, 0.05, 0.03, 0.02, 0.014). The formation of copolymer was proved by cyclic voltammogram study.