bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereoselective Synthesis of Tetrahydrofurans via the Palladium‐Catalyzed Reaction of Aryl Bromides with γ‐Hydroxy Alkenes: Evidence for an Unusual Intramolecular Olefin Insertion into a Pd(Ar)(OR) Intermediate.
Authors: Wolfe John P. , Rossi Michael A. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Cation Radical [3 + 2] Cycloaddition of Chalcone Epoxides: A Facile Synthesis of Highly Substituted Tetrahydrofurans.
Authors: Huo Congde , Jia Xiaodong , Zhang Wei , Yang Li , Lue Jianming , Liu Zhong‐Li 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Convenient Approach to the Synthesis of Fused Acetal Derivatives by Tetrabutylammonium Peroxydisulfate‐Mediated Oxidative Cycloaddition of 1,3‐Dicarbonyl Compounds to Cyclic Enol Ethers: A Rebuttal.
Authors: Jadhav Vidyadhar , Park Min Young , Kim Yong Hae 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis and X‐Ray Diffraction Study of 2‐(2‐Acyl‐1‐phenylethenyl)pyrroles.
Authors: Stepanova Z. V. , Sobenina L. N. , Mikhaleva A. I. , Ushakov I. A. , Elokhina V. N. , Vorontsov I. I. , Antipin M. Yu. , Trofimov B. A. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A New Series of Potent Oxindole Inhibitors of CDK2.
Authors: Luk Kin‐Chun , Simcox Mary Ellen , Schutt Andy , Rowan Karen , Thompson Thelma , Chen Yi , Kammlott Ursula , DePinto Wanda , Dunten Pete , Dermatakis Apos 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Ionic Liquid as an Efficient Promoting Medium for Fixation of CO2: Clean Synthesis of α‐Methylene Cyclic Carbonates from CO2 and Propargyl Alcohols Catalyzed by Metal Salts under Mild Conditions.
Authors: Gu Yanlong , Shi Feng , Deng Youquan 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis and in vitro Cytotoxicity of 5‐Substituted 2‐Cyanoimino‐4‐imidazodinone and 2‐Cyanoimino‐4‐pyrimidinone Derivatives.
Authors: Chern Jyh‐Haur , Shia Kak‐Shan , Chang Chung‐Ming , Lee Chung‐Chi , Lee Yen‐Chun , Tai Chia‐Liang , Lin Ying‐Ting , Chang Chih‐Shiang , Tseng Huan‐Yi 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Microwave‐Assisted Synthesis of Sterically Hindered 3‐(5‐Tetrazolyl)pyridines.
Authors: Bliznets Igor V. , Vasil'ev Andrei A. , Shorshnev Sergey V. , Stepanov Aleksandr E. , Lukyanov Sergey M. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
CAN‐Mediated Cyclization of Epoxypropyl Cinnamyl Ethers: A Facile Stereoselective Synthesis of Tetrahydropyran Derivatives.
Authors: Nair Vijay , Balagopal Lakshmi , Rajan Roshini , Deepthi Ani , Mohanan Kishor , Rath Nigam P. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 2‐(2‐Naphthyl)quinolines from Z‐3‐(2‐Naphthyl)‐3‐chloro‐2‐propenal.
Authors: Vashkevich E. V. , Potkin V. I. , Kozlov N. G. , Skakovskii E. D. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Facile Route to Pyrrolo[3′,4′:3,4]pyrido[1,2‐a]benzimidazoles: Novel Heterocyclic Derivatives.
Authors: Tereshchenko Alexander D. , Tolmachev Andrey A. , Tverdokhlebov Anton V. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Facile Synthesis of 6‐Aryl‐1‐methyl‐3‐n‐propyl‐6,7‐dihydro‐1H‐pyrazolo [4,3‐d]pyrimidin‐7‐ones.
Authors: Reddy N. Ram , Reddy G. Mahesh , Reddy P. Pratap 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Palladium‐Catalyzed Regiospecific Tandem Allylation of 2‐Aminophenols Using 2‐Butene‐1,4‐diol.
Authors: Yang Shyh‐Chyun , Lai Hwe‐Chen , Tsai Yan‐Chiu 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Selective Preparation of 1,3‐Butadienyl Phosphines, 1‐Iodo‐ and 1,4‐Diiodo‐butadienyl Phosphine Oxides via Zirconocene‐Mediated Cross‐Coupling of Alkynylphosphines.
Authors: Xi Zhenfeng , Zhang Wenxiong , Takahashi Tamotsu 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Efficient Synthesis of O‐, S‐, N‐ and C‐Glycosides of 2‐Amino‐2‐deoxy‐D‐glucopyranose from Glycosyl Iodides.
Authors: Miquel Nicolas , Vignando Stefano , Russo Giovanni , Lay Luigi 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Highly Stereoselective Synthesis of Aristeromycin Through Dihydroxylation of 4‐Aryl‐1‐azido‐2‐cyclopentenes.
Authors: Ainai Takauki , Wang Yong‐Gang , Tokoro Yuko , Kobayashi Yuichi 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Biosynthetic Capacities of Actinomycetes. Part 30. Lactonamycin Z, an Antibiotic and Antitumor Compound Produced by Streptomyces sanglieri Strain AK 623.
Authors: Hoeltzel Alexandra , Dieter Anke , Schmid Dietmar G. , Brown Rose , Goodfellow Michael , Beil Winfried , Jung Guenther , Fiedler Hans‐Peter 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Isolation, Structure and HIV‐1 Integrase Inhibitory Activity of Exophillic Acid, a Novel Fungal Metabolite from Exophiala pisciphila.
Authors: Ondeyka John G. , Zink Deborah L. , Dombrowski Anne W. , Polishook Jon D. , Felock Peter J. , Hazuda Daria J. , Singh Sheo B. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Stereodivergent and Reiterative Synthesis of Bistetrahydrofuran Ring Cores of Annonaceous Acetogenins.
Authors: Kojima Naoto , Maezaki Naoyoshi , Tominaga Hiroaki , Yanai Minori , Urabe Daisuke , Tanaka Tetsuaki 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Recent Developments in the Use of N‐Heterocyclic Carbenes: Applications in Catalysis
Authors: Kissling Rebecca M. , Viciu Mihai S. , Grasa Gabriela A. , Germaneau Romain F. , Gueveli Tatyana , Pasareanu Marie‐Christiane , Navarro‐Fernandez Oscar , Nolan Steven P. 
Published: June 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Polarographic Behavior of Gemfibrozil in the Presence of Dissolved Oxygen and Its Analytical Application
Authors: Xu Maotian , Song Junfeng , Guo Wei , Li Ning 
Published: June 2004

AbstractThe polarographic behavior of gemfibrozil is investigated in 0.2 mol L−1 KH2PO4‐Na2HPO4 (pH 5.8±0.1)‐8% ethanol supporting electrolyte in the absence and the presence of dissolved oxygen. The results demonstrate that the polarographic reduction peak at ca. −1.17 V is a catalytic hydrogen wave after deaeration, and the enhanced reduction peak in the presence of dissolved oxygen is the so‐called parallel catalytic hydrogen wave. Based on the parallel catalytic hydrogen wave, a novel method has been developed for the determination of gemfibrozil by single sweep polarography. Calibration plot is linear in the range of 1.8×10−7–2.4×10−6 mol L−1 and detection limit is 9.0×10−8 mol L−1. The proposed method is applied to the direct determination of the gemfibrozil in pharmaceutical preparations. The proposed method is simpler, faster and more sensitive than the known methods for gemfibrozil analyses.
Voltammetric Determination of Platinum in Plant Material
Authors: Kowalska Joanna , Huszal Sylwester , Sawicki Marek G. , Asztemborska Monika , Stryjewska Ewa , Szalacha Elzbieta , Golimowski Jerzy , Gawronski Stanislaw W. 
Published: June 2004

AbstractA very sensitive procedure for the determination of platinum in hydroponically cultivated plant samples (Sinapis alba L and Lolium perenne) is presented. A microwave digestion with HNO3, HClO4 and HCl acids with additional UV irradiation is followed by the platinum determination by adsorptive stripping voltammetry at hanging mercury drop electrode. The influence of HNO3 acid on voltammetric determination of platinum is discussed. For validation of the obtained results the recovery of Pt was examined and the Pt determination by ICP MS was carried out. The highest platinum amounts were found in the roots of the plants, nevertheless the effective transport of platinum to the steams and leaves was also observed.
Electrocatalytic Reduction of Oxygen at Multi‐Walled Carbon Nanotubes and Cobalt Porphyrin Modified Glassy Carbon Electrode
Authors: Qu Jianying , Shen Yan , Qu Xiaohu , Dong Shaojun 
Published: June 2004

AbstractThe multi‐walled carbon nanotubes (MWNTs) modified glassy carbon electrode exhibited electrocatalytic activity to the reduction of oxygen in 0.1 M HAc‐NaAc (pH 3.8) buffer solution. Further modification with cobalt porphyrin film on the MWNTs by adsorption, the resulted modified electrode showed more efficient catalytic activity to O2 reduction. The reduction peak potential of O2 is shifted much more positively to 0.12 V (vs. Ag/AgCl), and the peak current is increased greatly. Cyclic voltammetry (CV), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), were used to characterize the material and the modified film on electrode surface. Electrochemical experiments gave the total number of electron transfer for oxygen reduction as about 3, which indicated a co‐exist process of 2 electrons and 4 electrons for reduction of oxygen at this modified electrode. Meanwhile, the catalytic activities of the multilayer film (MWNTs/CoTMPyP)n prepared by layer‐by‐layer method were investigated, and the results showed that the peak current of O2 reduction increased and the peak potential shifted to a positive direction with the increase of layer numbers.
Monitoring of drugs and metabolites in body fluids by capillary electrophoresis with XeHg lamp‐based and laser‐induced fluorescence detection
Authors: Caslavska Jitka , Thormann Wolfgang 
Published: June 2004

AbstractCommercial capillary electrophoresis instrumentation with XeHg lamp‐based and laser induced fluorescence (LIF) detection is employed for analysis of urinary 3,4‐methylenedioxymethamphetamine (MDMA, Ecstasy) and its major metabolites, urinary metabolites of acetylsalicylic acid, urinary benzoylecgonine in an immunoassay format, and albendazole sulfoxide and albendazole sulfone in plasma. For the examples studied, the data suggest that the lamp‐based detector can be employed for the monitoring of pharmacological and toxicological relevant solute concentrations, and thus represents an attractive alternative to LIF detection.
High‐density lipoproteins contribute to the α‐1‐globulin zone in capillary electrophoresis of human serum proteins
Authors: Luraschi Paola , Pagani Anna , Infusino Ilenia , Moraschinelli Irene , Franzini Carlo 
Published: June 2004

Abstractα‐1‐Antitrypsin (AAT) and α‐1‐acid glycoprotein (AAG) are reported to be the main proteins contributing to the α‐1‐globulin capillary zone electrophoresis (CZE) zone, but the sum (AAT + AAG) showed lower than the α‐1‐globulin. We investigated the role of high‐density lipoprotein (HDL), an additional protein migrating in the α‐1‐globulin zone, as a possible cause for such a gap. In a set of 98 sera we measured the α‐1‐globulin with a dedicated clinical capillary electrophoresis system, and AAT, AAG and apolipoprotein A‐1 (ApoA) by immunonephelometry. The α‐1‐globulin were consistently higher than the sum (AAT + AAG), by (mean value ± standard deviation) 1.70 ± 0.88 g/L in 49 sera with low ApoA, and by 3.59 ± 0.75 g/L in 49 sera with high ApoA. Corresponding figures in the comparison α‐1‐globulin/(AAT + AAG + ApoA) were reduced to 1.08 ± 0.77 g/L and 1.67 ± 0.70 g/L. It is concluded that HDL significantly contribute to the CZE α‐1‐globulin zone, but do not completely explain the differences between the electrophoretic and the immunochemical measurements. However, CZE α‐1‐globulin measurements give information about increases of the two major acute phase proteins comparable to specific protein measurements.
Fenofibrate and fenofibric acid analysis by capillary electrophoresis
Authors: Shihabi Zak K. 
Published: June 2004

AbstractA capillary electrophoresis method has been developed to measure fenofibrate in capsules based on micellar electrokinetic capillary chromatography with detection at 280 nm using a borate buffer containing sodium dodecyl sulfate (SDS). However, the metabolite of this drug (fenofibric acid) in serum and whole blood was analyzed by capillary zone electrophoresis (CZE) in a borate‐carbonate buffer using acetonitrile stacking. The analysis is rapid, < 7 min with no interferences. Incubation of fenofibrate in whole blood caused hydrolysis of the ester bond with the release of fenofibric acid.
Conflicting results between electrophoresis methods of serum M‐proteins
Authors: Wuyts Birgitte , Bossuyt Xavier , Verhoef Gregor , Blanckaert Norbert , Delanghe Joris R. 
Published: June 2004

AbstractThe quantification of monoclonal immunoglobulins by protein electrophoresis has been helpful in determining the prognosis for the patient. In a 65‐year old man with documented IgG λ monoclonal gammopathy, a discrepancy in the detection and quantification of this M‐protein was found when studied by four different electrophoretic methods. On a high‐resolution agarose method with acid violet staining a prominent peak was seen in the fast γ‐region. A lower resolution agarose method using an amido black staining showed a small mid‐γ restriction, and no spike was detected by high‐resolution or lower resolution capillary zone electrophoresis. The discrepancy was not attributable to a migration in the β‐region leading to masking by transferrin or C3 peak, incorrect separation on CZE due to a high isoelectric point (pI > 8.5) or pentamerization of IgM M‐proteins. Therefore, other causes for discrepancies should be investigated.
Determination of aminothiols in body fluids, cells, and tissues by capillary electrophoresis
Authors: Bayle Christophe , Caussé Elisabeth , Couderc François 
Published: June 2004

AbstractOxidative stress is present in cardiovascular diseases and hyperhomocysteinemia, an independant risk factor for these diseases. It may play a role by inducing production of oxygen free radicals. Reduced glutathione is the most abundant intracellular low‐molecular‐weight thiol and plays an essential role in protecting cells from toxic species. The thiol‐containing compounds which are the most often considered in biological analysis, are homocysteine (Hcy), cysteine (Cys), glutathione (GSH), cysteinyl‐glycine (Cys‐Gly), γ‐glutamyl‐cysteine (γGlu‐Cys), and their derivatives. These aminothiols are present in body fluids or cells, associated with proteins or occur free (reduced and oxidized). These free forms may play a role in the pathogenesis of disease. Because Hcy (with Cys) exhibits pro‐oxidative properties and GSH (with Cys‐Gly) antioxidative properties, and because there is extensive interconversion between these metabolites, their simultaneous analysis in biological samples is necessary to examine their role in human disease. Capillary electrophoresis (CE) seems to be a solution to reach this goal. No extensive review reports the analysis of aminothiols using CE. This review describes the different CE approaches which have been used to separate and assay aminothiols, and the different obtained datas.
Analysis of organic components of smokeless gunpowders: High‐performance liquid chromatogaphyvs.micellar electrokinetic capillary chromatography
Authors: Cascio Orazio , Trettene Maristella , Bortolotti Federica , Milana Gabriella , Tagliaro Franco 
Published: June 2004

AbstractThe aim of the present study was to verify the analytical performances of high‐performance liquid chromatography (HPLC) and micellar electrokinetic capillary chromatography (MEKC) for the separation and qualitative determination of a selected group of organic components of smokeless gunpowders. The HPLC method was based on a gradient reversed‐phase elution with a mobile phase composed of 0.17 MH3PO4/methanol; detection was performed by UV absorption at the wavelengths of 220, 254, and 270 nm. The MEKC experiments were carried out by using uncoated fused‐silica capillaries (50 μm inside diameter, 50 cm effective length) and a running buffer composed of 10 mMsodium tetraborate at pH 9.24 added with 25 mMsodium dodecyl sulfate (SDS); the applied voltage was 25 kV; detection was either at a fixed wavelength UV of 214 nm or with a diode‐array detector operating in the wavelength range from 190 to 350 nm. Both reversed‐phase HPLC and MEKC techniques succeeded in resolving the tested standard mixtures of organic components of smokeless powders. Although the sequence of elution of the different analytes was slightly different between HPLC and MEKC, a statistical analysis based on the Spearman's rank correlation test showed that the two separation patterns were highly correlated. HPLC and MEKC were comparable in terms of elution/migration time precision, whereas MEKC showed higher reproducibility of peak areas. The interfacing of capillary electrophoresis with diode array UV detection provided distinct UV spectra of the individual analytes, thus improving, on the detection side, the analytical selectivity and identification power of capillary electrophoresis.
Stacking and low‐temperature technique in nonaqueous capillary electrophoresis for the analysis of 3,4‐methylenedioxymethamphetamine
Authors: Tsai Chih‐Hsin , Fang Ching , Liu Ju‐Tsung , Lin Cheng‐Huang 
Published: June 2004

AbstractLow‐temperature and ambient‐temperature nonaqueous stacking techniques in capillary electrophoresis (CE) are described for the first time. A low‐temperature bath was used to control the temperature from ambient to subzero degrees, by which a novel hyphenated method, low‐temperature bath‐nonaqueous capillary electrophoresis stacking (LTB‐NACE stacking) is demonstrated. 3,4‐Methylenedioxymethamphetamine (3,4‐MDMA) was determined at a concentration of 4.7×10−6 M (at a 92.1% confidence level) by normal nonaqueous capillary zone electrophoresis (NACZE) and this was improved to 2.6×10−8 M and 5.0×10−9 M, respectively, when the NACZE stacking and LTB‐NACZE stacking techniques were applied. The content of 3,4‐MDMA in an illicit drug and a suspect urine sample was readily detected. Upon application of the LTB to the separation of isomers the resolution (R) for the separation of 2,3‐/3,4‐MDMA was improved from 0.6 (LTB, 22°C) to 1.6 (LTB, −55°C) and for (+)3,4‐MDMA/(−)3,4‐MDMA, from 0.4 (LTB, 25°C) to 1.0 (LTB, −10°C).
Capillary electrophoresis and mass spectrometry for screening of metabolic disorders in newborns
Authors: Šenk Petr , Kozák Libor , Foret František 
Published: June 2004

AbstractClinical analyses always represent a challenge for the sensitivity and selectivity of the analytical techniques. Of the most critical are the techniques required for the quick determination of the disease state and application of the proper treatment in newborns. This short critical review overviews the present state of the art of the use of mass spectrometry and capillary electrophoresis for screening of metabolic disorders in newborns.
Determination of salbutamol enantiomers in human urine using heptakis(2,3‐di‐O‐acetyl‐6‐O‐sulfo)‐β‐cyclodextrin in nonaqueous capillary electrophoresis
Authors: Servais Anne‐Catherine , Chiap Patrice , Hubert Philippe , Crommen Jacques , Fillet Marianne 
Published: June 2004

AbstractNonaqueous capillary electrophoresis (NACE) was successfully applied to the resolution and the determination of salbutamol enantiomers in urine samples using heptakis(2,3‐di‐O‐acetyl‐6‐O‐sulfo)‐β‐cyclodextrin (HDAS‐β‐CD). After optimization of the electrophoretic parameters, namely the background electrolyte (BGE) composition and the HDAS‐β‐CD concentration, salbutamol enantiomers were completely resolved using a BGE made up of 10 mM ammonium formate and 15 mM HDAS‐β‐CD in methanol acidified with 0.75 M formic acid. Isoprenaline was selected as internal standard. Solid‐phase extraction (SPE) was used for sample cleanup prior to the CE separation. Different sorbents involving polar, nonpolar interactions or dual retention mechanisms were evaluated and extraction cartridges containing both nonpolar and strong cation‐exchange functionalities were finally selected. Salbutamol enantiomers recoveries from urine samples were determined. The method was then successfully validated using a new approach based on accuracy profiles over a concentration range from 375 to 7500 ng/mL for each enantiomer.
Capillary and microelectrophoretic separations of ligase detection reaction products produced from low‐abundant point mutations in genomic DNA
Authors: Thomas Gloria , Sinville Rondedrick , Sutton Shelby , Farquar Hannah , Hammer Robert P. , Soper Steven A. , Cheng Yu‐Wei , Barany Francis 
Published: June 2004

AbstractCapillary gel electrophoresis (CGE) and polymer‐based microelectrophoretic platforms were investigated to analyze low‐abundant point mutations in certain gene fragments with high diagnostic value for colorectal cancers. The electrophoretic separations were carried out on single‐stranded DNA (ssDNA) products generated from an allele‐specific ligation assay (ligase detection reaction, LDR), which was used to screen for a single base mutation at codon 12 in the K‐ras oncogene. The presence of the mutation generated a ssDNA fragment that was >40 base pairs (bp) in length, while the primers used for the ligation assay were <30 bp in length. Various separation matrices were investigated, with the success of the matrix assessed by its ability to resolve the ligation product from the large molar excess of unligated primers when the mutant allele was lower in copy number compared to the wild‐type allele. Using CGE, LDR product models (44 and 51 bp) could be analyzed in a cross‐linked polyacrylamide gel with a 1000‐fold molar excess of LDR primers (25 bp) in ∼45 min. However, when using linear polyacrylamide gels, these same fragments could not be detected due to significant electrokinetic biasing during injection. A poly(methylmethacrylate) (PMMA) microchip of 3.5 cm effective column length was used with a 4% linear polyacrylamide gel to analyze the products generated from an LDR. When the reaction contained a 100‐fold molar excess of wild‐type DNA compared to a G12.2D mutant allele, the 44 bp ligation product could be effectively resolved from unligated primers in under 120 s, nearly 17 times faster than the CGE format. In addition, sample cleanup was simplified using the microchip format by not requiring desalting of the LDR prior to loading.
Characterization of the interaction between human complement protein C4 and a single‐chain variable fragment antibody by capillary electrophoresis and surface plasmon resonance
Authors: Seifar Reza M. , Cool Robbert H. , Quax Wim J. , Bischoff Rainer 
Published: June 2004

AbstractImmunoaffinity capillary electrophoresis and surface plasmon resonance have been used for the characterization of the interaction between two large‐sized proteins, the human complement protein C4 and the single‐chain variable fragment C43. The rather high kinetic rate constants as determined by surface plasmon resonance pointed out that a capillary electrophoresis method had to be applied, in which the labeled C4 is preincubated with C43 before injection and the same concentration of C43 is included in the running buffer. Analysis of the concentration dependence of the small mobility shift of the fluorescent C4 signal upon binding of C43 resulted in a dissociation constant that was comparable to the one obtained with surface plasmon resonance. This study is one of the few examples where capillary electrophoresis is successfully used to characterize the interaction between large proteins.