bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Flavonoid Glycosides from Neolitsea Sericea var. Aurata via the General Method and HPLC‐SPE‐NMR
Authors: Lam Sio‐Hong , Chen Chien‐Kuang , Wang Jeng‐Shu , Lee Shoei‐Sheng 
Published: May 2015

AbstractSix flavonoid rhamnosides (1‐2, 4‐7) were separated from the water‐soluble non‐alkaloidal portion of the EtOH extract of the leaves of Neolitsea sericea var. aurata using various chromatographic techniques including Sephadex LH‐20, centrifugal partition chromatography, and RP‐18 Lobar. One additional compound (3) besides these six was identified by application of HPLC‐SPE‐NMR in a flavonoid rich fraction. The latter approach consumed only 1.5 mg of samples, theoretically equivalent to 0.2 g of dry leaves. This study demonstrates that HPLC‐SPE‐NMR has great advantage over the general methods on the aspects of manpower, research time, amounts of plant materials, and consumables in separation and characterization of natural products.
BF3‐OEt2‐Mediated Rearrangement of (4‐Phenylpiperidin‐4‐Yl)‐Arylmethanols
Authors: Chang Meng‐Yang , Wu Tsun‐Cheng , Lin Shiang‐Tsern 
Published: May 2015

AbstractSynthesis of several 4‐benzhydrylidenepiperidine analogs has been established starting from different (4‐phenylpiperidin‐4‐yl)‐arylmethanols via boron trifluoride etherate mediated rearrangement. The possible rearranged mechanism was proposed. Boron trifluoride etherate‐mediated rearrangement of the related derivatives was also examined. It presents a novel rearrangement reaction catalyzed by boron trifluoride etherate and broadens the scope of application.
Liquid‐Liquid Microextraction Coupled with High Performance Liquid Chromatography for Determination of Palladium
Authors: Dong Yan‐Jie 
Published: May 2015

AbstractLiquid‐liquid microextraction (LLME) coupled with high performance liquid chromatography (HPLC) for the analysis of palladium is described. The analytes were extracted from a 10.0 mL aqueous sample into organic phase. The extraction time was 20 min. Factors such as pH in aqueous phase, extraction times, and stirring rate were optimised. The method was applied for determination of palladium in mixture samples. The linearity range was from 1.0 to 100 nM and the detection limit was 0.12 nM. Relative standard deviations (%, n = 5) were 0.41 to 0.74. All experiments were carried out at room temperature, 35±0.2 °C.
Simultaneous Separation of Four Types of Steroid Hormones by Micellar Electrokinetic Chromatography with Cetyltrimethylammonium Bromide
Authors: Chang Lin‐Chau , Chiu Tai‐Chia , Lee Shoei‐Sheng , Kuo Ching‐Hua , Chang Tien‐Chun 
Published: May 2015

AbstractMicellar electrokinetic chromatography (MEKC) using a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was applied to simultaneous separation of four types of hydrophobic steroid hormones including androgens, estrogens, progestins, and glucocorticoids. Various parameters, such as the concentration of CTAB, type and proportion of organic modifiers, and sample matrix have been demonstrated to be important with respect to the separation resolution, analysis time, and repeatability. Successful separation of cortisone, hydrocortisone, estriol, testosterone, estrone, progesterone, and estradiol was achieved at −25 kV using 100 mM Tris‐boric acid buffer (pH 9.0) containing 40 mM CTAB and 20% 2‐propanol using ultraviolet (UV) absorption detection. For estrogen compounds which possess intrinsic fluorescence, detection limits at the sub μM level could be achieved with laser‐induced fluorescence (LIF) detection. Two kinds of pharmaceutical preparations were analyzed using the developed method, and the results were in good agreement with the label claims.
Reductive Dehalogenation of Arylhalides and Alkylhalides with Zinc in THF Saturated Aqueous Ammonium Chloride
Authors: Hekmatshoar Rahim , Sajadi Sodeh , Heravi Majid M. 
Published: May 2015

AbstractA low‐cost and highly effective zinc/THF‐saturated aqueous ammonium chloride has been developed for dehalogenation of arylhalides and alkylhalides in aqueous systems.
Optical Resolution of 5‐Oxo‐1‐Phenyl‐Pyrazolidine‐3‐Carboxylic Acid as a New Organocatalyst for Organic Reactions
Authors: Tzeng Zheng‐Hao , Yang Shuen‐Wen , Liu Pang‐Min , Chen Kwun‐Min 
Published: May 2015

AbstractOptical resolution of racemic 5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid 2 with L‐amino acid methyl ester via the diastereomers formation was investigated. Treatment of racemic 5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid 2 with L‐valine methyl ester gave diastereomers with a total yield of 86%. The diastereomeric dipeptides can be easily separated by flash column chromatography. Acidic cleavage of the derived diastereomers gave both the optically pure (+)‐(R)‐ and (‐)‐(S)‐5‐oxo‐1‐phenyl‐pyrazolidine‐3‐carboxylic acid ((+)‐(R)‐2 and (‐)‐(S)‐2) with a total yield of 94% and 95%, respectively.
Halocyclization of Methyl 2‐Alkynylbenzoates to Isocoumarins Using Cupric Halides
Authors: Chin Ling‐Yu , Lee Chia‐Ying , Lo Yu‐Hsiang , Wu Ming‐Jung 
Published: May 2015

AbstractTreatment of methyl 2‐alkynylbenzoates with two to three equivalents of CuX2 (X = Cl or Br) in refluxing acetonitrile gave isocoumarins 2 in good to excellent chemical yields.
Copper‐Catalyzed Amidation of Aryl Iodides in the Presence of Various Chelating Ligands
Authors: Hosseinzadeh Rahman , Golchoubian Hamid , Masoudi Mahtab 
Published: May 2015

AbstractN,N′‐Dibenzylethylenediamine is presented as a new, efficient, and versatile bidentate ligand suitable for the copper catalyzed formation of the C‐N bond. This bidentate ligand has been demonstrated to facilitate the copper catalyzed cross‐coupling reactions of aryl iodides with amides to afford the desired products in good to excellent yields.
Novel and Efficient Procedure for the Regiocontrolled Preparation of α‐(Phenylsulfanyl) Carbonyl Compounds
Authors: Lee Fa‐Yen , Zhu Jia‐Liang 
Published: May 2015

AbstractA new procedure for the regiocontrolled synthesis of α‐(phenylsulfanyl) carbonyl compounds has been developed, making use of lithium naphthalenide induced reductive sulfenylation of α‐cyano carbonyl compounds as a key operation. Through this protocol, a variety of á‐(phenylsulfanyl) carbonyl compounds has been prepared in moderate to high yields. The completely regioselective sulfenylation was observed in most of the cases.
Design and Synthesis of 1‐(6‐(2‐(2‐Arylethynyl)Phenyl)Hexyn‐5‐yl)Piperidin‐2‐Ones as Antitumor Agents that Induce Apoptotic Progress
Authors: Lin I‐Ling , Chen I‐Hsiang , Lin Chi‐Fong , Lo Yu‐Hsiang , Yang Sheng‐Huei , Lin Shinne‐Ren , Wu Ming‐Jung 
Published: May 2015

AbstractA series of 1‐(6‐(2‐(2‐arylethynyl)phenyl)hexyn‐5‐yl)piperidin‐2‐ones 2a‐j were synthesized and their antitumor activities were evaluated. Of these compounds, 1‐(6‐(2‐(2‐(4‐nitrophenyl)ethynyl)phenyl)hexyn‐5‐yl)piperidin‐2‐one (2j) showed the highest potency of growth inhibition activity, especially against the RPMI‐8226 (0.4 μM) and SR (0.02 μM) cell lines of human leukemia. Compound 2j also induced significant apoptotic progress in the cell cycle assay with the K‐562 cell line.
Vanadyl Sulfate (VOSO4.3H2O). An Efficient Catalyst for Acylation of Alcohols and Phenols under Solvent Free Condition
Authors: Oskooie Hossein A. , Baghernezhad Bita , Heravi Majid M. , Beheshtiha Y. Sh. 
Published: May 2015

AbstractAlcohols and phenols were efficiently acylated with acetic anhydride in the presence of vanadyl sulfate (VOSO4.3H2O) at room temperature in high yields.
Simultaneous Spectrophotometric Determination of Zinc and Nickel in Water Samples by Mean Centering of Ratio Kinetic Profiles
Authors: Madrakian Tayyebeh , Moein Roshanak , Bahram Morteza 
Published: May 2015

AbstractThe mean centering of ratio kinetic profiles method was used for the simultaneous determination of binary mixtures of Ni(II) and Zn(II) in water samples, without prior separation steps. The method is based on the difference in the rate of the reaction of Ni(II) and Zn(II) with xylenol orange at pH 5.3. The method allows rapid and accurate determination of Ni(II) and Zn(II). The analytical characteristics of the methods for the simultaneous determination of binary mixtures of Ni(II) and Zn(II) were calculated. The linear range was 0.025‐2.400 μg mL−1 and 0.025‐2.20 μg mL−1 for Zn(II) and Ni(II), respectively. Interference effects of common anions and cations were studied, and the method was successfully applied to the simultaneous determination of Zn(II) and Ni(II) in water samples.
Voltammetric Determination of Adrenaline Using a Poly(1‐Methylpyrrole) Modified Glassy Carbon Electrode
Authors: Aslanoglu Mehmet , Kutluay Aysegul , Karabulut Serpil , Abbasoglu Sultan 
Published: May 2015

AbstractA voltammetric method using a poly(1‐methylpyrrole) modified glassy carbon electrode was developed for the quantification of adrenaline. The modified electrode exhibited stable and sensitive current responses towards adrenaline. Compared with a bare GCE, the modified electrode exhibits a remarkable shift of the oxidation potentials of adrenaline in the cathodic direction and a drastic enhancement of the anodic current response. The separation between anodic and cathodic peak potentials (ΔEp) for adrenaline is 30 mV in 0.1 M phosphate buffer solution (PBS) at pH 4.0 at modified glassy carbon electrodes. The linear current response was obtained in the range of 7.5 × 10−7 to 2.0 × 10−4 M with a detection limit of 1.68 × 10−7 M for adrenaline by square wave voltammetry. The poly(1‐methypyrrole)/GCE was also effective to simultaneously determine adrenaline, ascorbic acid and uric acid in a mixture and resolved the overlapping anodic peaks of these three species into three well‐defined voltammetric peaks in cyclic voltammetry. The modified electrode has been successfully applied for the determination of adrenaline in pharmaceuticals. The proposed method showed excellent stability and reproducibility.
Kinetic Spectrophotometric Analysis and Spectrofluorimetric Analysis of Ciprofloxacin Hydrochloride and Norfloxacin in Pharmaceutical Preparations Using 4‐Chloro‐7‐Nitrobenzo‐2‐Oxa‐1,3‐Diazole (NBD‐Cl)
Authors: Abdel‐Hay Mohamed H. , Hassan Ekram M. , Gazy Azza A. , Belal Tarek S. 
Published: May 2015

AbstractSimple, reliable, sensitive and accurate kinetic spectrophotometric and spectrofluorimetric methods were proposed for the determination of ciprofloxacin hydrochloride (CPX) and norfloxacin (NRX) in pure form and in pharmaceuticals. The methods are based on coupling the studied drugs with 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD‐Cl) in the presence of alkaline borate buffer. Spectrophotometric measurement was achieved by recording the absorbance at 477 nm after a fixed time of 20 and 15 min on a water bath adjusted at 70 ± 1 °C for CPX and NRX, respectively. The same product exhibited emission peaks at 540 nm. The different experimental parameters affecting the development and stability of the color were carefully studied and optimized. The absorbance concentration plots were linear over the ranges 3‐18 and 2.5‐15.0 μg/mL for CPX and NRX, respectively, while the fluorescence concentration plots were linear over the ranges 0.06‐0.36 and 0.05‐0.30 μg/mL for CPX and NRX, respectively. The limit of detection of the kinetic method was about 0.2 μg/mL for both drugs while the fluorescence measurement enabled their detection at a concentration of about 0.012 μg/mL. The proposed methods were successfully applied for the assay of the two drugs in their commercial products. The results obtained were statistically compared with those obtained by reference HPLC and spectrophotometric methods. The stoichiometry of the reaction was determined and the reaction pathway was postulated.
Cytotoxic Activity of Capnellene‐8β, 10α‐Diol Derivatives from a Taiwanese Soft Coral Capnella sp.
Authors: Shen Ya‐Ching , Tzeng Guo‐Lin , Kuo Yau‐Haur , Khalil Ashraf Taha 
Published: May 2015

AbstractThe sesquiterpene capnellene‐8β, 10α‐diol (1) was isolated from non‐polar extract of the soft coral Capnella sp. Ten acylation products of capnellene‐8β, 10α‐diol were prepared: 10α‐hydroxy‐8β‐O‐benzoylcapnellene (2), 10α‐hydroxy‐8β‐O‐p‐toluoylcapnellene (3), 10α‐hydroxy‐8β‐O‐4‐chlorobenzoyl‐capnellene (4), 10α‐hydroxy‐8β‐O‐2‐furoylcapnellene (5), 10α‐hydroxy‐8β‐O‐2‐thiophenoylcapnellene (6), 10α‐hydroxy‐8β‐O‐4‐fluorobenzoylcapnellene (7), 10α‐hydroxy‐8β‐O‐4‐propylbenzoylcapnellene (8), 10α‐hydroxy‐8β‐O‐cinnamoylcapnellene (9), 10α‐hydroxy‐8β‐O‐4‐nitrobenzoylcapnellene (10), and 10α‐hydroxy‐8β‐O‐4‐anisoylcapnellene (11). The structures of capnellene‐8β, 10α‐diol as well as its derivatives were established through standard spectroscopic analysis. The in vitro cytotoxic activities of the eleven compounds were evaluated against Hela, KB, Daoy, and WiDr human tumor cell lines.
Pyridinium Iodochloride: An Efficient Reagent for Iodination of Hydroxylated Aromatic Ketones and Aldehydes
Authors: Khansole Sandeep V. , Mokle Shyam S. , Sayyed Mudassar A. , Vibhute Yeshwant B. 
Published: May 2015

AbstractDirect iodination of several reactive aromatic compounds like hydroxy substituted acetophenones and aldehydes with pyridinium iodochloride (PyICl) proceeded smoothly to afford the corresponding aromatic iodides in good to excellent yield. Pyridinium iodochloride has been found to be an efficient solid iodinating reagent with no hazardous effect and it can be handled safely.
Hypervalent Iodine(III) Sulfonate Reagent Mediated Synthesis of 4‐Aryl‐2‐Phenyloxazoles in Ionic Liquid
Authors: Cheng Hui‐Ting , Hou Rei‐Sheu , Wang Huey‐Min , Chen Ling‐Ching 
Published: May 2015

AbstractA new and efficient method for the synthesis of 4‐aryl‐2‐phenyloxazoles is described which is based upon the reaction of α‐[(2,4‐dinitrobenzene)sulfonyl]oxy ketone intermediates with benzamide in ionic liquid.
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

AbstractThe 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

AbstractA 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

AbstractRoom 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

AbstractIn 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

AbstractA 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

AbstractCondensation 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

AbstractAn 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

AbstractAn 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.