bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Stereoselective Total Synthesis and Structural Elucidation of (‐)‐Indoxamycins A—F.
Authors: He Chi , Zhu Chenlong , Wang Bingnan , Ding Hanfeng 
Published: April 2015

AbstractNone of the compounds show significant cytotoxic activities against HT‐29 and A‐549 tumor cell lines.
ChemInform Abstract: Inorganic Molybdenum Octahedral Nanosized Cluster Units, Versatile Functional Building Block for Nanoarchitectonics
Authors: Cordier S. , Grasset F. , Molard Y. , Amela‐Cortes M. , Boukherroub R. , Ravaine S. , Mortier M. , Ohashi N. , Saito N. , Haneda H. 
Published: April 2015

AbstractReview: 125 refs.
ChemInform Abstract: Oxindole as Starting Material in Organic Synthesis
Authors: Ziarani Ghodsi Mohammadi , Gholamzadeh Parisa , Lashgari Negar , Hajiabbasi Parvin 
Published: April 2015

AbstractReview: advances in the use of oxindole as starting material in the synthesis of various organic compounds and drugs; 128 refs.
Synthesis and Properties of a Novel Pyridineoxazoline Containing Optically Active Helical Polymer as a Catalyst Ligand for Asymmetric Diels–Alder Reaction
Authors: Wang Heng , Li Na , Zhang Jie , Wan Xinhua 
Published: April 2015

AbstractA novel pyridineoxazoline (PyOx) containing helical polymer, poly{(–)‐(S)‐4‐tert‐butyl‐2‐[5‐(4‐tert‐butylphenyl)‐3‐vinylpyridin‐2‐yl]‐oxazoline} (PA), was designed and synthesized to approach the effect of chain conformation on the catalytic property. Its complex with Cu(OTf)2, i.e., Cu(II)-PA, was employed to catalyze the homogeneous Diels–Alder (D–A) reaction of alkenoyl pyridine N‐oxides with cyclopentadiene in tetrahydrofuran. Compared with the previously reported copper complex, Cu(II)-P1 (RSC Advances, 2015, 5, 2882), which was derived from a nonhelical poly[(–)‐(S)‐4‐tert‐butyl‐2‐(3‐vinylpyridin‐2‐yl)‐oxazoline], Cu(II)-PA exhibited a remarkably enhanced enantioselectivity and reaction rate. However, its enantioselectivity was lower than the Cu(II) complex of (–)‐(S)‐4‐tert‐butyl‐2‐[5‐(4‐tert‐butylphenyl)‐3‐vinylpyridin‐2‐yl]‐oxazoline (Cu(II)-A), a low molar mass model compound. Chirality 27:523–531, 2015. © 2015 Wiley Periodicals, Inc.
Development of Chiral Building Blocks Having a Bicyclo[3.3.0]Octane Framework Using a Diastereomeric Resolution‐Selective Deprotection
Authors: Tamura Masafumi , Oyamada Miki , Shirataki Yoshiaki 
Published: April 2015

AbstractA protocol is presented for an efficient and practical approach to the synthesis of enantiomerically pure bicyclo[3.3.0]octane derivatives from achiral Cs‐symmetric bicyclo[3.3.0]octane‐2,8‐dione using a diastereomeric resolution‐selective deprotection method. This method affords chiral building blocks having bicyclo[3.3.0]octane framework with the same site of diastereotopic carbonyl functional group. Chirality 27:364–369, 2015. © 2015 Wiley Periodicals, Inc.
Eucalyptol aus Eukalyptusöl
Authors: Neumann Wilma , Siehl Hans‐Ullrich , Zeller Klaus‐Peter , Berger Stefan , Sicker Dieter 
Published: April 2015

AbstractEucalyptol (1,8‐Cineol) ist ein cyclischer Monoterpenether und Hauptinhaltsstoff des ätherischen Eucalyptusöls, das aus Eukalyptusblättern durch Wasserdampfdestillation gewonnen wird. Eukalypten sind eine artenreiche anpassungsfähige Pflanzengattung. Der unbedachte Eukalyptus‐Anbau in warmen Ländern zeigte aber als Schattenseiten den enormen Wasserverbrauch und die verdrängende Wirkung als invasive Art auf einheimische Pflanzen. Das Öl und Eucalyptol selbst finden medizinische Anwendung. Überdosierung ist schädlich. Einige Kräuter und Gewürze, wie Basilikum und Kardamom, enthalten Eucalyptol als prägenden Aromaträger. Eucalyptol ist zwar achiral, aber spektroskopisch durchaus nicht einfach. Rohstoff für die Isolierung ist Eucalyptusöl, das destilliert und chromatografiert wird. Alle analytischen Spektren werden vollständig entweder im Hauptteil oder in der supporting information wiedergegeben und interpretiert.
Iridium‐ and Osmium‐decorated Reduced Graphenes as Promising Catalysts for Hydrogen Evolution
Authors: Lim Chee Shan , Sofer Zdeněk , Toh Rou Jun , Eng Alex Yong Sheng , Luxa Jan , Pumera Martin 
Published: April 2015

AbstractRenewable energy sources are highly sought after as a result of numerous worldwide problems concerning the environment and the shortage of energy. Currently, the focus in the field is on the development of catalysts that are able to provide water splitting catalysis and energy storage for the hydrogen evolution reaction (HER). While platinum is an excellent material for HER catalysis, it is costly and rare. In this work, we investigated the electrocatalytic abilities of various graphene–metal hybrids to replace platinum for the HER. The graphene materials were doped with 4f metals, namely, iridium, osmium, platinum and rhenium, as well as 3d metals, namely, cobalt, iron and manganese. We discovered that a few hybrids, in particular iridium‐ and osmium‐doped graphenes, have the potential to become competent electrocatalysts owing to their low costs and—more importantly—to their promising electrochemical performances towards the HER. One of the more noteworthy observations of this work is the superiority of these two hybrids over MoS2, a well‐known electrocatalyst for the HER.
Development and validation of receptor occupancy pharmacodynamic assays used in the clinical development of the monoclonal antibody vedolizumab
Authors: Wyant Tim , Estevam Jose , Yang Lili , Rosario Maria 
Published: April 2015

BackgroundVedolizumab is a monoclonal antibody approved for use in ulcerative colitis and Crohn's disease. By specifically binding to α4β7 integrin, vedolizumab prevents trafficking of lymphocytes to the gut, thereby interfering with disease pathology. During the clinical development program, the pharmacodynamic effect of vedolizumab was evaluated by 2 flow cytometry receptor occupancy assays: act‐1 (ACT‐1) and mucosal addressin cell adhesion molecule‐1 (MAdCAM‐1). Here we describe the development and validation of these assays.MethodsThe ACT‐1 assay is a receptor occupancy free‐site assay that uses a monoclonal antibody with the same binding epitope as vedolizumab to detect free (unbound) sites on α4β7 integrin. The MAdCAM‐1 assay used a soluble version of the natural ligand for α4β7 integrin to detect free sites. The assays were validated using a fit‐for‐purpose approach throughout the clinical development of vedolizumab.ResultsBoth the ACT‐1 assay and the MAdCAM‐1 assay demonstrated acceptable reproducibility and repeatability. The assays were sufficiently stable to allow for clinical use. During clinical testing the assays demonstrated that vedolizumab was able to saturate peripheral cells at all doses tested.ConclusionsTwo pharmacodynamic receptor occupancy assays were developed and validated to assess the effect of vedolizumab on peripheral blood cells. The results of these assays demonstrated the practical use of flow cytometry to examine pharmacodynamic response in clinical trials. © 2015 International Clinical Cytometry Society
The routine leukocyte differential flow cytometryHematoFlow™ method: A new flagging system for automatic validation
Authors: Allou Kaoutar , Vial Jean‐Philippe , Béné Marie C , Lacombe Francis 
Published: April 2015

The complete blood cell count and white blood cell differential are the first step in the biological diagnosis of hematological diseases. Both are currently performed by automated instruments which control data and produce alerts. If such flags are activated, the automated differential cannot be validated and the operator must activate a visual blood smear review. Microscopic examination is still today the reference method despite its lack of sensitivity and reproducibility. The HematoFlow™ (Beckman Coulter) system is the first flow cytometry commercialized method designed for the routine differential. Using six markers in five colors and an automated gating strategy, it provides differentials proven to be reliable for 17 leukocyte subpopulations detection.Relying first on a retrospective analysis of 6,462 blood samples processed by HematoFlow™, thresholds were determined to detect the presence of immature granulocytes and/or blast cells. All possible gating strategy misclassifications of leukocyte subpopulations were then summarized in a systematic nomenclature leading to the development of an original flag system based on the detection of aberrant localization of cell events in specific new bivariate histograms. Ultimately, more than 50% of the results could be automatically validated using the HematoFlow™ system, without any false negative, thereby dramatically contributing to an important decrease of technicians’ workload. Moreover a noticeable help was given for smear review interpretation and new immunological flags led to the confirmation of blood disease after classical immunophenotyping.These results were confirmed in a second prospective study including 15,335 cases, where more than 50% of the results were automatically validated by this new flag system. MFC stands as being more and more essential for analyzing differentials in routine and this new flag system could greatly improve its implementation. © 2015 International Clinical Cytometry Society
Sc(OTf)3‐Catalysed [3+3] Annulation of Cyclopropane 1,1‐Diesters with Mercaptoacetaldehyde: A Facile Strategy for the Synthesis of Tetrahydrothiopyranols
Authors: Wang Hua‐Peng , Zhang Huan‐Huan , Hu Xiu‐Qin , Xu Peng‐Fei , Luo Yong‐Chun 
Published: April 2015

AbstractA catalytic [3+3] annulation of cyclopropane 1,1‐diesters with in‐situ‐generated mercaptoacetaldehyde for the synthesis of polyfunctionalized tetrahydrothiopyran derivatives has been developed. A ring‐opening/aldol cascade reaction catalysed by Sc(OTf)3 (10 mol‐%) gave a series of tetrahydrothiopyranols in good yields. Simple derivatization of the products gave some useful compounds.
Impact of Perforation on Hydraulic Fracture Initiation and Extension in Tight Natural Gas Reservoirs
Authors: Lei Xin , Zhang Shicheng , Xu Guoqing , Zou Yushi 
Published: April 2015

AbstractIn the exploitation of tight natural gas reservoirs, increasing the number of fractures to enlarge the stimulated reservoir volume is the key point. Furthermore, high breakdown pressure is the primary factor that causes the difficulty of hydraulic fracturing treatment in a tight gas reservoir. Both of these factors are related closely to the perforation strategy. However, the impact of perforation on hydraulic fracture initiation and extension in a tight gas reservoir has not yet been researched in an experimental way. We designed a piece of equipment that we refer to as a mini‐sized true tri‐axial hydraulic fracturing simulation system (8 cm×8 cm×10 cm) for the experiments. By using this equipment, we could simulate hydraulic fracturing using downhole drilling cores, which were acquired from the Erdos basin tight gas reservoir. We mainly examined the influence of the horizontal stress difference and spacing, density, and depth of perforation on the fracture patterns. Experimental results show that, in specimens without perforation, the number of fractures is less than that of the perforation specimens, and the direction of fractures is uncontrollable. In specimens with perforations, fractures initiate at the perforation points, which is conducive to forming fractures uniformly. The perforation spacing and horizontal stress difference strongly influence the interaction among fractures. The interaction among fractures is mitigated as the perforation spacing or the horizontal stress difference increases. The depth of perforation affects the fracture initiation. Factures are easier to initiate and propagate in deeper perforations. The existence of perforation could effectively reduce the breakdown pressure by approximately 18 %.
Was a Pyrimidine‐Pyrimidine Base Pair the Ancestor of Watson‐Crick Base Pairs? Insights from a Systematic Approach to the Origin of RNA
Authors: Cafferty Brian J. , Hud Nicholas V. 
Published: April 2015

AbstractUncovering the origin of RNA is essential for understanding the origins of life. The persistent inability of chemists to identify a plausible prebiotic route to RNA polymers, along with the seemingly optimal structure of RNA for its functions in extant life, argue in favor of the hypothesis that RNA is a product of chemical or biological evolution. To understand the origin of RNA, we must consider which molecules could have originally acted in place of RNA’s substructures (i.e., nucleobases (the recognition units), ribose (a trifunctional connector), and phosphate (an ionized linker)) in the oldest ancestor of RNA (or proto‐RNA). Major challenges to uncovering the chemical structure of proto‐RNA include finding molecules that would have spontaneously undergone molecular selection and covalent assembly into an RNA‐like polymer, within the complex mixture of the “prebiotic soup” and without the aid of enzymes. In this review, we discuss progress towards identifying the recognition units of proto‐RNA and mechanisms by which the ancestral nucleobases might have been originally selected and incorporated into polymers. We consider possible proto‐nucleobases within the chemical space of the heterocycles defined by the purines and pyrimidines that have H, NH2, or O as exocyclic groups (which includes the extant nucleobases). Taking into account the results of numerous experiments that have explored nucleic acids with alternative backbones and noncanonical nucleobases, we are able to remove about half of these 81 molecules from candidacy as ancestral nucleobases. A particularly encouraging result of this approach is the identification of two molecules, 2,4,6‐triaminopyrimidine and barbituric acid, which look very promising as possible nucleobases of proto‐RNA.
Enhanced Thermal Stability of Inverted Polymer Solar Cells with Pentacene
Authors: Yang Feng , Kim Jae‐Hyoung , Ge Ziyi , Kim Yong‐Sang 
Published: April 2015

AbstractIn this study, we focused on the thermal stability of organic solar cells based on poly(3‐hexylthiophene) (P3HT) and (6,6)‐phenyl C61‐butyric acid methyl ester (PCBM), fabricated by blends of P3HT : PCBM : pentacene. Enhanced thermal stability of organic solar cells was achieved by introducing pentacene (Pc) into blends of P3HT : PCBM in organic solar cells with the structure indium tin oxide/ZnO/P3HT : PCBM : Pc/poly(3,4‐ethylenedioxythiophene) : polystyrene sulfonate/Ag (ITO/ZnO/P3HT : PCBM : Pc/PEDOT : PSS/Ag). The donor‐acceptor interfaces of devices with Pc were more stable than those without Pc in the active layer. During the thermal annealing process, the Pc in the P3HT : PCBM blends suppressed the crystallization of P3HT and PCBM, which was confirmed by optical microscopic images and UV‐visible absorption spectra. The power conversion efficiency (PCE) of the device with Pc was reduced to no less than 70 % of its original efficiency after keeping it at 120 °C for 24 hours, while that of the non‐Pc device was reduced to 13 % of its original efficiency after 24 hours at the same temperature. Based on these results, we propose a new Pc‐blended organic solar cell that has advantages in the thermal annealing process.
Effectiveness of a CBT Intervention for Persistent Insomnia and Hypnotic Dependency in an Outpatient Psychiatry Clinic
Authors: Taylor Hannah Lund , Rybarczyk Bruce D. , Nay William , Leszczyszyn David 
Published: April 2015

ObjectiveTo test cognitive‐behavioral therapy for insomnia (CBT‐I) in patients who not only receive psychiatric treatment in a outpatient psychiatry clinic but also continue to experience chronic insomnia despite receiving pharmacological treatment for sleep. CBT‐I included an optional module for discontinuing hypnotic medications.MethodPatients were randomized to 5 sessions of individual CBT‐I (n = 13) or treatment as usual (n = 10). Sleep parameters were assessed using sleep diaries at pre‐ and posttreatment. Questionnaires measuring depression, anxiety, and health‐related quality of life were also administered.ResultsCBT‐I was associated with significant improvement in sleep, with 46% obtaining normal global sleep ratings after treatment. However, no changes in secondary outcomes (depression, anxiety, quality of life) were obtained and no patients elected to discontinue their hypnotic medications.ConclusionsPatients with complex, chronic psychiatric conditions can obtain sleep improvements with CBT‐I beyond those obtained with pharmacotherapy alone; however, sleep interventions alone may not have the same effect on mental health outcomes in samples with more severe and chronic psychiatric symptoms and dependency on hypnotic medications.
Steady‐state pharmacokinetics and bioavailability of immediate‐release and extended‐release formulations of lamotrigine in elderly epilepsy patients: Use of stable isotope methodology
Authors: Polepally Akshanth R. , Remmel Rory P. , Brundage Richard C. , Leppik Ilo E. , Rarick John O. , Ramsay R. Eugene , Birnbaum Angela K. 
Published: April 2015

AbstractA classic 2‐period crossover bioavailability study was conducted to evaluate the relative and absolute bioavailability of immediate‐release (IR) and extended‐release (XR) lamotrigine formulations under steady‐state conditions in elderly patients with epilepsy. On treatment days, each subject's morning dose (IR or XR lamotrigine) was replaced with an intravenous 50‐mg dose of stable‐labeled lamotrigine. Lamotrigine concentrations were measured at 13 points between 0 and 96 hours. XR and IR lamotrigine formulations were similar with respect to steady‐state area under the concentration‐time curve from 0 to 24 hours (AUC0–24 h ss), average concentration (Cavg, ss), and trough concentration (Cτ, ss). A 33% lower fluctuation in concentrations with XR was observed relative to IR lamotrigine. The time to peak concentration (Tmax, ss) was delayed for XR lamotrigine (3.0 vs 1.3 hours) with lower peak concentration (15% lower). The absolute bioavailability for IR and XR formulations was 73% and 92%, respectively. The formulations were bioequivalent with respect to AUC0–24 h ss, Cτ, ss, and Cavg, ss indicating that it may be possible to switch directly from IR to XR lamotrigine without changes in the total daily dose.
Microbiological and chemical safety concerns regarding frozen fillets obtained from Pangasius sutchi and Nile tilapia exported to European countries
Authors: Kulawik Piotr , Migdał Władysław , Gambuś Florian , Cieślik Ewa , Özoğul Fatih , Tkaczewska Joanna , Szczurowska Katarzyna , Wałkowska Izabela 
Published: April 2015

AbstractBACKGROUNDMicrobiological and chemical safety concerns regarding frozen fillets from pangasius catfish (Pangasius hypophthalmus) exported to Poland, Germany and Ukraine and Nile tilapia (Oreochromis niloticus) exported to Poland and Germany were investigated by analyzing heavy metal residues, microbiological hazards, biogenic amines, and thiobarbituric acid (TBA) and total volatile basic nitrogen (TVB‐N) content.RESULTSThe heavy metal residues from all studied samples were far lower than the limits established by authorities. The most abundant biogenic amine found was histamine, with a maximum content of 9.6 mg 100 g−1, found in pangasius exported to Poland. The total viable counts were from 2.8 log cfu g−1 in pangasius exported to Ukraine to 4.3 log cfu g−1 in pangasius exported to Germany. Vibrio spp. were present in 70–80% of all studied pangasius groups, whereas there no Vibrio spp. were found in the studied tilapia samples. 30% of Pangasius fillets exported to Poland were contaminated with coagulase‐positive staphylococci. No E. coli was found in any of the studied samples. Although the results of TBA analysis differed significantly between studied groups, the malonic aldehyde content in all studied groups was still very low. The TVB‐N content in frozen fillets from pangasius was significantly lower than in frozen tilapia fillets.CONCLUSIONSWe reported that pangasius catfish frozen fillets were widely contaminated with Vibrio spp., which could prove hazardous for the final consumer if the fish is eaten raw or undercooked. The rest of the analysis showed no other reason for concern associated with Nile tilapia and Pangasius catfish frozen fillet consumption. © 2015 Society of Chemical Industry
Rate Constants and Activation Energies for Gas‐Phase Reactions of Three Cyclic Volatile Methyl Siloxanes with the Hydroxyl Radical
Authors: Safron Andreas , Strandell Michael , Kierkegaard Amelie , Macleod Matthew 
Published: April 2015

ABSTRACTReaction with hydroxyl radicals (OH) is the major pathway for removal of cyclic volatile methyl siloxanes (cVMS) from air. We present new measurements of second‐order rate constants for reactions of the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) with OH determined at temperatures between 313 and 353 K. Our measurements were made using the method of relative rates with cyclohexane as a reference substance and were conducted in a 140‐mL gas‐phase reaction chamber with online mass spectrometry analysis. When extrapolated to 298 K, our measured reaction rate constants of D4 and D5 with the OH radical are 1.9 × 10−12 (95% confidence interval (CI): (1.7–2.2) × 10−12) and 2.6 × 10−12 (CI: (2.3–2.9) × 10−12) cm3 molecule−1 s−1, respectively, which are 1.9× and 1.7× faster than previous measurements. Our measured rate constant for D6 is 2.8 × 10−12 (CI: (2.5–3.2) × 10−12) cm3 molecule−1 s−1 and to our knowledge there are no comparable laboratory measurements in the literature. Reaction rates for D5 were 33% higher than for D4 (CI: 30–37%), whereas the rates for D6 were only 8% higher than for D5 (CI: 5–10%). The activation energies of the reactions of D4, D5, and D6 with OH were not statistically different and had a value of 4300 ± 2800 J/mol.
The use of isoprene as a novel dopant in negative ion atmospheric pressure photoionization mass spectrometry coupled to high‐performance liquid chromatography
Authors: Dousty Faezeh , O'Brien Rob 
Published: April 2015

RationaleAs in the case with positive ion atmospheric pressure photoionization (PI‐APPI), the addition of dopants significantly improves the sensitivity of negative ion APPI (NI‐APPI). However, the research on dopant‐assisted‐NI‐APPI has been quite limited compared to the studies on dopant‐assisted PI‐APPI. This work presents the potential of isoprene as a novel dopant for NI‐APPI.MethodsThirteen compounds, possessing suitable gas‐phase ion energetic properties in order to make stable negative ions, were selected. Dopants were continuously introduced into a tee junction prior to the ion source through a fused‐silica capillary, while analytes were directly injected into the same tee. Then both were mixed with the continuous solvent from high‐performance liquid chromatography (HPLC), nebulized, and entered the source. The nebulized stream was analyzed by APPI tandem quadrupole mass spectrometry in the negative ion mode.ResultsThe results obtained using isoprene were compared with those obtained by using toluene as a dopant and dopant‐free NI‐APPI. Isoprene enhanced the ionization intensities of the studied compounds, which were found to be comparable and, in some cases, more effective than toluene. The mechanisms leading to the observed set of negative analyte ions were also discussed. Because in NI‐APPI, thermal electrons, which are produced during the photoionization of a dopant, are considered the main reagent ions, both isoprene and toluene promoted the ionization of analytes through the same mechanisms, as expected.ConclusionsIsoprene was shown to perform well as a novel dopant for NI‐APPI. Isoprene has a high photoabsorption cross section in the VUV region; therefore, its photoionization leads to a highly effective production of thermal electrons, which further promotes the ionization of analytes. In addition, isoprene is environmentally benign and less toxic compared to currently used dopants. Copyright © 2015 John Wiley & Sons, Ltd.