bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: An Efficient Method of Synthesis of Isoxazolidine‐Fused β‐Lactams via Base‐Promoted Cyclization—Ring Opening of Carbamoylspirocyclopropane Isoxazolidines.
Authors: Tran Tung Q. , Savinkov Ruslan S. , Diev Vyacheslav V. , Starova Galina L. , Molchanov Alexander P. 
Published: October 2013

AbstractA novel type of β‐lactame derivatives (IV) can be synthesized by base‐promoted cyclization‐cyclopropane ring opening of isoxazolidines (III) which in turn are readily prepared by 1,3‐dipolar cycloaddition of C‐carbamoyl nitrones (I) with methylenecyclopropanes (II).
ChemInform Abstract: Synthesis and Biological Evaluation of Novel Bis[1,2,4]triazolo[3,4‐b][1,3,4]oxadiazoles.
Authors: Reddy Ch. Sanjeeva , Devi M. Vani , Kumar G. Rajesh , Sunitha M. , Nagaraj A. 
Published: October 2013

AbstractNewly synthesized title compounds (VII) are screened for their activity against a panel of Gram‐positive bacteria.
ChemInform Abstract: Synthesis and Spectra Characteristics of Novel 3‐(para‐Bromophenyl)‐7‐(substituted vinyl) Coumarins.
Authors: Wang Lingyun , Zou Hanxun , Ye Decheng , Cao Derong 
Published: October 2013

AbstractNovel coumarin derivatives (I) are synthesized via Perkin condensation and Wittig olefination.
ChemInform Abstract: Chiral Organic Contact Ion Pairs in Metal‐Free Catalytic Enantioselective Oxidative Cross‐Dehydrogenative Coupling of Tertiary Amines to Ketones.
Authors: Zhang Gen , Ma Yunxia , Wang Shoulei , Kong Weidong , Wang Rui 
Published: October 2013

AbstractThis novel, efficient, and environmentally friendly title reaction affords tetrahydroisoquinoline derivatives from simple starting materials and under mild conditions in satisfactory yields with good diastereo‐ and enantioselectivities.
ChemInform Abstract: Synthesis of Fluorine‐Containing Multisubstituted Phenanthridines by Rhodium‐Catalyzed Alkyne [2 + 2 + 2] Cycloaddition and Tandem sp2 C—H Difluoromethylenation.
Authors: Li Yajun , Zhu Jiangtao , Zhang Lisi , Wu Yongming , Gong Yuefa 
Published: October 2013

AbstractPhenanthridines (III) and (V) are obtained by Rh‐catalyzed diyne cycloaddition reactions, offering a mild and direct method for the construction of multisubstituted phenanthridines with good functional group tolerance.
ChemInform Abstract: Contrasting Behavior of NBS Towards 1,4‐Dihydrobenzothieno[3,2‐b]pyridine 5,5‐Dioxides and 4,5‐Dihydro‐1H‐indeno[1,2‐b]pyridines.
Authors: Sobolev Arkadij , et al. et al. 
Published: October 2013

AbstractBenzothienopyridine dioxides (I) react with NBS under mild conditions to yield fully aromatized products (II) directly whereas the analogous indenones (III) give stable bromides (IV) which are not prone to dehydrobromination.
ChemInform Abstract: Stereoselective Synthesis of 2,5‐Disubstituted Morpholines Using a Palladium‐Catalyzed Hydroamination Reaction.
Authors: McGhee Alicia , Cochran Brian M. , Stenmark Torrey A. , Michael Forrest E. 
Published: October 2013

AbstractThe regioselective opening of aziridines (I) with allyl alcohol proceeds readily in the presence of a Lewis acid.
ChemInform Abstract: Synthesis of Novel 2,4‐Disubstituted 3H‐Pyrido[3,2‐e][1,4]diazepin‐5‐ones and 2,4‐Disubstituted 3H‐Pyrido[2,3‐e][1,4]diazepin‐5‐ones Derivatives via Regioselective Thionation and Nucleophilic Substitutions Reactions.
Authors: El Bouakher Abderrahman , Prie Gildas , Aadil Mina , Akssira Mohamed , Viaud‐Massuard Marie‐Claude 
Published: October 2013

AbstractThe synthesis of the title compounds (VI) as potentially pharmacologically relevant structures is detailed.
ChemInform Abstract: New Phosphine Oxide Aziridinyl Phosphonates as Chiral Lewis Bases for the Abramov‐Type Phosphonylation of Aldehydes.
Authors: Dogan Oezdemir , Isci Muhammet , Aygun Muhittin 
Published: October 2013

AbstractNewly synthesized chiral aziridine bisphosphonates are examined for the phosphonylation of aldehydes.
ChemInform Abstract: Potassium tert‐Butoxide‐Mediated Synthesis of Unsymmetrical Diaryl Ethers, Sulfides and Selenides from Aryl Bromides.
Authors: Kumar Amit , Bhakuni Bhagat Singh , Prasad Ch. Durga , Kumar Shailesh , Kumar Sangit 
Published: October 2013

AbstractKOtBu In DMSO can be efficiently used for the synthesis of unsymmetrical diaryl sulfides and selenides from diaryl dichalcogenides and aryl bromides.
ChemInform Abstract: Synthesis of 2,6‐Disubstituted Pyridin‐3‐yl C‐2′‐Deoxyribonucleosides Through Chemoselective Transformations of Bromo‐chloropyridine C‐Nucleosides.
Authors: Kubelka Tomas , Slavetinska Lenka , Eigner Vaclav , Hocek Michal 
Published: October 2013

AbstractStandard Pd‐catalyzed cross‐coupling reactions proceed chemoselectively at the position of the bromine, whereas nucleophilic substitutions are unselective.
Design and Generation of Highly Diverse Fluorinated Fragment Libraries and their Efficient Screening with Improved 19F NMR Methodology
Authors: Vulpetti Anna , Dalvit Claudio 
Published: October 2013

AbstractFragment screening performed with 19F NMR spectroscopy is becoming increasingly popular in drug discovery projects. With this approach, libraries of fluorinated fragments are first screened using the direct‐mode format of the assay. The choice of fluorinated motifs present in the library is fundamental in order to ensure a large coverage of chemical space and local environment of fluorine (LEF). Mono‐ and poly‐fluorinated fragments to be included in the libraries for screening are selected from both in‐house and commercial collections, and those that are ad hoc designed and synthesized. Additional fluorinated motifs to be included in the libraries derive from the fragmentation of compounds in development and launched on the market, and compounds contained in other databases (such as Integrity, PDB and ChEMBL). Complex mixtures of highly diverse fluorine motifs can be rapidly screened and deconvoluted in the same NMR tube with a novel on the fly combined procedure for the identification of the active molecule(s). Issues and problems encountered in the design, generation and screening of diverse fragment libraries of fluorinated compounds with 19F NMR spectroscopy are analyzed and technical solutions are provided to overcome them. The versatile screening methodology described here can be efficiently applied in laboratories with limited NMR setup and could potentially lead to the increasing role of 19F NMR in the hit identification and lead optimization phases of drug discovery projects.
Evaluation of endobronchial ultrasound‐guided fine‐needle aspirations (EBUS‐FNA): Correlation with adequacy and histologic follow‐up
Authors: Karunamurthy Arivarasan , Cai Guoping , Dacic Sanja , Khalbuss Walid E. , Pantanowitz Liron , Monaco Sara E. 
Published: October 2013

BACKGROUNDEndobronchial ultrasound‐guided fine‐needle aspiration (EBUS‐FNA) is a minimally invasive modality for diagnosing mediastinal lesions. When determining adequacy, EBUS‐FNAs are evaluated for diagnostic material or sufficient lymphoid tissue. In this study, the authors evaluated their experience with EBUS‐FNAs and correlated the findings with adequacy and histologic follow‐up.METHODSEBUS‐FNAs were retrospectively reviewed over a 3‐year period and correlated with the clinicopathologic findings, adequacy, and histologic follow‐up.RESULTSIn total, 593 EBUS‐FNAs were obtained from 356 patients, including 420 (71%) satisfactory (SAT) cases, 107 (18%) less than optimal (LTO) cases, and 66 (11%) unsatisfactory (UNSAT) cases. The overall diagnostic yield was 71%, and the mediastinal (N2) lymph nodes had better yield (72%) than the peripheral intrapulmonary and hilar (N1) lymph nodes (64%). Histologic follow‐up was available in 203 cases (34%), and malignancy was identified in 7 UNSAT cases (23%), 6 LTO‐negative cases (11%), and 4 SAT cases (3%) with a negative cytologic diagnosis. In the suboptimal cases with follow‐up, 79% were benign and 21% were malignant on follow‐up, including 25 (14%) with fibrosis or hyalinization. The sensitivity, specificity, and positive and negative predictive values in the study were 80%, 100%, 100%, and 95%, respectively.CONCLUSIONSThe current data demonstrated that EBUS‐FNA has good sensitivity, high specificity, and a higher diagnostic yield for N2 lymph nodes compared with N1 lymph nodes. The data also illustrate the finding that suboptimal cases have a greater risk of false‐negative diagnoses and a 21% chance of malignancy, including processes with fibrosis or hyalinization. Cancer (Cancer Cytopathol) 2014;122:23–32. © 2013 American Cancer Society.
A new efficient method for synaptic vesicle quantification reveals differences between medial prefrontal cortex perforated and nonperforated synapses
Authors: Nava Nicoletta , Chen Fenghua , Wegener Gregers , Popoli Maurizio , Nyengaard Jens Randel 
Published: October 2013

ABSTRACTCommunication between neurons is mediated by the release of neurotransmitter‐containing vesicles from presynaptic terminals. Quantitative characterization of synaptic vesicles can be highly valuable for understanding mechanisms underlying synaptic function and plasticity. We performed a quantitative ultrastructural analysis of cortical excitatory synapses by mean of a new, efficient method, as an alternative to three‐dimensional (3D) reconstruction. Based on a hierarchical sampling strategy and unequivocal identification of the region of interest, serial sections from excitatory synapses of medial prefrontal cortex (mPFC) of six Sprague‐Dawley rats were acquired with a transmission electron microscope. Unbiased estimates of total 3D volume of synaptic terminals were obtained through the Cavalieri estimator, and adequate correction factors for vesicle profile number estimation were applied for final vesicle quantification. Our analysis was based on 79 excitatory synapses, nonperforated (NPSs) and perforated (PSs) subtypes. We found that total number of docked and reserve‐pool vesicles in PSs significantly exceeded that in NPSs (by, respectively, 77% and 78%). These differences were found to be related to changes in size between the two subtypes (active zone area by 86%; bouton volume by 105%) rather than to postsynaptic density shape. Positive significant correlations were found between number of docked and reserve‐pool vesicles, active zone area and docked vesicles, and bouton volume and reserve pool vesicles. Our method confirmed the large size of mPFC PSs and a linear correlation between presynaptic features of typical hippocampal synapses. Moreover, a greater number of docked vesicles in PSs may promote a high synaptic strength of these synapses. J. Comp. Neurol. 522:284–297, 2014. © 2013 Wiley Periodicals, Inc.
Scalable, privacy preserving radio‐frequency identification protocol for the internet of things
Authors: Asadpour Mahdi , Dashti Mohammad Torabi 
Published: October 2013

SummaryIt is now possible to embed radio‐frequency identification tags into almost any physical device. However, issues regarding privacy remain a concern and limit their widespread use. We propose a scalable anonymous radio‐frequency identification authentication protocol using what we refer to as anonymous tickets. These tickets uniquely identify tags and are reusable. This considerably strengthens its non‐traceability and requires just search/query time, with minimal storage overhead on the back‐end system. We formally prove the protocol and compare the performance of the proposed protocol with selected works found in literature. Copyright © 2013 John Wiley & Sons, Ltd.
Helical Self‐Assembly of Optically Active Phthalocyanine Derivatives: Effect of ZnO Coordination Bond on Morphology and Handedness of Nanostructures
Authors: Zhang Congcong , Jing Lu , Lin Sha , Hao Zijuan , Tian Jing , Zhang Xiaomei , Zhu Peihua 
Published: October 2013

AbstractTwo optically active phthalocyanine derivatives with eight peripheral chiral (S)‐4′‐(2‐methylbutoxy)biphenyl moieties on the β‐position of the phthalocyanine ring are synthesized. The circular dichroism (CD) spectra show signals in the Q absorption region for both compounds 1 and 2 in chloroform solution, indicating the effective chiral‐information transfer from the peripheral chiral (S)‐4′‐(2‐methylbutoxy)biphenyl side chains to the phthalocyanine chromophore at the molecular level. Their self‐assembling properties are further investigated by using electronic absorption and Fourier transform infrared spectroscopy, transmission electronic microscopy, scanning electronic microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Experimental results reveal the effect of the metal‐coordination bond on molecular packing models in these nanostructures, which in turn results in the self‐assembled nanostructures with different morphologies, from nanosheets for 1 to helical nanofibers for 2. In addition, good semiconducting properties of the nanostructures fabricated from phthalocyanine derivatives 1 and 2 are revealed by current–voltage measurements.
Quantification of Hydrogen Sulfide and Methanethiol and the Study of Their Scavenging by Biocides of the Isothiazolone Family
Authors: Frerot Eric , Bagnoud Alain , Cicchetti Esmeralda 
Published: October 2013

AbstractA sensitive analytical method for the quantification of malodourous hydrogen sulfide (H2S) and methanethiol (CH3SH) was developed and validated. The method consisted of solid‐phase microextraction with concomitant in‐fibre derivatisation of the mercaptan using N‐ethylmaleimide. The adducts were analysed by GC–MS using a triple quadrupole in the selected reaction monitoring mode. The limits of detection of solutions of H2S and CH3SH in water were 100 and 10 ng L−1, respectively, below their odour‐perception thresholds. The analytical method was used to show the scavenging effect of 1,2‐benzisothiazol‐3(2H)‐one (Proxel) and 2‐methyl‐4‐isothiazolinone. The mechanism by which H2S and CH3SH are trapped with Proxel was studied by ultraperformance liquid chromatography (UPLC)‐MS.
Mixed Co–Mn Oxide‐Catalysed Selective Aerobic Oxidation of Vanillyl Alcohol to Vanillin in Base‐Free Conditions
Authors: Jha Ajay , Patil Kashinath R. , Rode Chandrashekhar V. 
Published: October 2013

AbstractManganese‐doped cobalt mixed oxide (MnCo‐MO) catalyst was prepared by a solvothermal method. The as‐prepared catalyst was characterised by X‐ray photoelectron spectroscopy, H2 temperature‐programmed reduction, O2 temperature‐programmed oxidation and XRD. This catalyst gave 62 % conversion with 83 % selectivity to vanillin in 2 hours for the liquid‐phase air oxidation of vanillyl alcohol without using base. Three different types of metal oxides were observed in the prepared catalyst, which could be identified as Co3O4, Mn3O4 and CoMn2O4. Among these, the tetragonal phase of CoMn2O4 was found to be more active and selective for vanillyl alcohol oxidation than Co3O4 and Mn3O4. High‐resolution TEM characterisation revealed the morphology of MnCo‐MO nanorods with a particle size of 10 nm. Successful recycling of the catalyst was also established in this oxidation reaction.
Study on Oxidation State Dependent Electrocatalytic Ability for I−/I3− Redox Reaction of Reduced Graphene Oxides
Authors: Yeh Min‐Hsin , Lin Lu‐Yin , Huang Tzu‐Yen , Chuang Hui‐Min , Chu Chih‐Wei , Ho Kuo‐Chuan 
Published: October 2013

AbstractThe influence of oxidation states on electrocatalytic abilities for I3− reduction is discussed for reduced graphene oxide (rGO), which is a promising catalyst of counter electrodes for dye‐sensitized solar cells (DSSCs). The oxidation states of rGO can be controlled via a photothermal reduction process by varying exposure times. The results reveal that the rGO with lower oxidation state shows smaller charge transfer resistance at the electrode/electrolyte interface and better electrocatalytic ability attributed to higher standard heterogeneous rate constant (k0) and reasonable electrochemical surface area (Ae) for I3− reduction, both are quantitatively determined by a rotating disk electrode system using the KouteckýLevich equation.
Electrochemical Detection of TNT at Cobalt Phthalocyanine Mediated Screen‐Printed Electrodes and Application to Detection of Airborne Vapours
Authors: Caygill J. Sarah , Collyer Stuart D. , Holmes Joanne L. , Davis Frank , Higson Séamus P. J. 
Published: October 2013

AbstractWe describe the use of cobalt phthalocyanine as a mediator to improve the sensitivity for the electrochemical detection of TNT. Commercial screen‐printed electrodes containing cobalt phthalocyanine were employed for determination of TNT. Improved sensitivities compared to screen‐printed carbon electrodes without phthalocyanine were observed, current response for cyclic voltammetric measurements at modified electrodes being at least double that of unmodified electrodes. A synergistic effect between oxygen and TNT reduction was also observed. Correlation between TNT concentrations and sensor output was observed between 0–200 µM TNT. Initial proof‐of‐concept experiments combining electrochemical determinations, with the use of an air‐sampling cyclone, are also reported.
A nonconforming finite element method for the Stokes equations using the Crouzeix‐Raviart element for the velocity and the standard linear element for the pressure
Authors: Lamichhane Bishnu P. 
Published: October 2013

SUMMARYWe present a finite element method for Stokes equations using the Crouzeix‐Raviart element for the velocity and the continuous linear element for the pressure. We show that the inf‐sup condition is satisfied for this pair. Two numerical experiments are presented to support the theoretical results. Copyright © 2013 John Wiley & Sons, Ltd.
THE IMPACT OF THE EURO CRISIS ON THE FINANCIAL PERFORMANCE OF EUROPEAN AND NORTH AMERICAN FIRMS
Authors: Filbeck Greg , Louie Kenneth , Zhao Xin 
Published: October 2013

AbstractIn this paper, we investigate the impact of the changes in European percentage sales before and after the Euro crisis for both US‐based and European‐based companies, both overall and across industries. We find that larger firms are associated with a decrease in return on assets (ROAs) in the post‐crisis era; the largtest of these large firms are associated with an increase in ROAs after the crisis. In addition, European (North American) headquartered companies experience a statistically significant decrease (increase) in European sales after controlling for the additional control variables such as industry. Overall, we note that companies which have lower European sales and strategically move their sales out of Europe after crisis experienced an increase in ROA. This result is robust after controlling for endogeneity issues. Copyright © 2013 John Wiley & Sons, Ltd.
Rapid determination of quetiapine in blood by gas chromatography–mass spectrometry. Application to post‐mortem cases
Authors: López‐Guarnido Olga , Tabernero María Jesús , Hernández Antonio F. , Rodrigo Lourdes , Bermejo Ana M. 
Published: October 2013

ABSTRACTA simple, fast and sensitive method for the determination of quetiapine in human blood has been developed and validated. The method involved a basic liquid–liquid extraction procedure and subsequent analysis by gas chromatography–mass spectrometry, previous derivatization with bis(trimethylsilyl)‐trifluoro‐acetamide and chorotrimethylsilane (99 : 1). The methods of validation included linearity with a correlation coefficient > 0.99 over the range 0.02–1 µg ml–1, intra‐ and interday precision (always < 12%) and accuracy (mean relative error always < 12%) to meet the bioanalytical acceptance criteria. The limit of detection was 0.005 µg ml–1. The procedure was further applied to post mortems from the Institute of Legal Medicine, University of Santiago de Compostela. Copyright © 2013 John Wiley & Sons, Ltd.
A Canonical EF‐Loop Directs Ca2+‐Sensitivity in Phospholipase C‐η2
Authors: Popovics Petra , Lu Jin , Nadia Kamil L. , Morgan Kevin , Millar Robert P. , Schmid Ralf , Blindauer Claudia A. , Stewart Alan J. 
Published: October 2013

ABSTRACTPhospholipase C‐η (PLCη) enzymes are a class of phosphatidylinositol 4,5‐bisphosphate‐hydrolyzing enzymes involved in intracellular signaling. PLCη2 can sense Ca2+ (stimulated by ∼1 µM free Ca2+) suggesting that it can amplify transient Ca2+ signals. PLCη enzymes possess an EF‐hand domain composed of two EF‐loops; a canonical 12‐residue loop (EF‐loop 1) and a non‐canonical 13‐residue loop (EF‐loop 2). Ca2+‐binding to synthetic peptides corresponding to EF‐loops 1 and 2 of PLCη2 and EF‐loop 1 of calmodulin (as a control) was examined by 2D‐[1H,1H] TOCSY NMR. Both PLCη2 EF‐loop peptides bound Ca2+ in a similar manner to that of the canonical calmodulin EF‐loop 1, particularly at their N‐terminus. A molecular model of the PLCη2 EF‐hand domain, constructed based upon the structure of calmodulin, suggested both EF‐loops may participate in Ca2+‐binding. To determine whether the EF‐hand is responsible for Ca2+‐sensing, inositol phosphate accumulation was measured in COS7 cells transiently expressing wild‐type or mutant PLCη2 proteins. Addition of 70 µM monensin (a Na+/H+ antiporter that increases intracellular Ca2+) induced a 4‐ to 7‐fold increase in wild‐type PLCη2 activity. In permeabilized cells, PLCη2 exhibited a ∼4‐fold increase in activity in the presence of 1 µM free Ca2+. The D256A (EF‐loop1) mutant exhibited a ∼10‐fold reduction in Ca2+‐sensitivity and was not activated by monensin, highlighting the involvement of EF‐loop 1 in Ca2+‐sensing. Involvement of EF‐loop 2 was examined using D292A, H296A, Q297A, and E304A mutants. Interestingly, the monensin responses and Ca2+‐sensitivities were largely unaffected by the mutations, indicating that the non‐canonical EF‐loop 2 is not involved in Ca2+‐sensing. J. Cell. Biochem. 115: 557–565, 2014. © 2013 Wiley Periodicals, Inc.
Osteoblast Adhesion Dynamics: A Possible Role for ROS and LMW‐PTP
Authors: Fernandes Gustavo V. O. , Cavagis Alexandre D. M. , Ferreira Carmen V. , Olej Beni , de Souza Leão Maurício , Yano Cláudia L. , Peppelenbosch Maikel , Granjeiro José Mauro , Zambuzzi Willian F. 
Published: October 2013

ABSTRACTReactive oxygen species (ROS) modulate a variety of intracellular events, but their role in osteoblast adhesion and spreading remains unclear. ROS is a very‐known physiological modulators of Protein Tyrosine Phosphatases activities, mainly to low molecular weight protein tyrosine phosphatase (LMW‐PTP) activity. As this biological mechanism is not clear in osteoblast adhesion, we decided to investigate ROS levels and phosphorylations of FAK and Src, identifying these proteins as potential substrates to LMW‐PTP activity. Our results showed that during osteoblast adhesion/spreading (30 min and 2 h of seeding) the intracellular ROS content (hydrogen peroxide) is finely regulated by an effective anti‐oxidant system [catalase and Superoxide Dismutase (SOD) activities were evaluated]. During the first 30 min of adhesion, there was an increase in ROS production and a concomitant increase in focal adhesion kinase (FAK) activity after its phosphorylation at Tyrosine 397 (Y397). Moreover, after 2 h there was a decrease in ROS content and FAK phosphorylation. There was no significant change in LMW‐PTP expression at 30 min or 2 h. In order to validate our hypothesis that LMW‐PTP is able to control FAK activity by modulating its phosphorylation status, we decided to overexpress and silence LMW‐PTP in this context. Our results showed that FAK phosphorylation at Y397 was increased and decreased in osteoblasts with silenced or overexpressed LMW‐PTP, respectively. Together, these data show that ROS modulate FAK phosphorylation by an indirect way, suggesting that a LMW‐PTP/FAK supra‐molecular complex is involved in transient responses during osteoblast adhesion and spreading. J. Cell. Biochem. 115: 1063–1069, 2014. © 2013 Wiley Periodicals, Inc.