bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold‐Catalyzed Carboalkoxylations of 2‐Ethynylbenzyl Ethers to form 1‐ and 2‐Indanones Chemoselectively: Effects of Ligands and Solvents
Authors: Wang Chiou‐Dong , Hsieh Yi‐Feng , Liu Rai‐Shung 
Published: January 2014

AbstractThe selective syntheses of 1‐ and 2‐indanone compounds from 2‐ethynylbenzyl ethers have been achieved with suitable catalysts and solvents. The highly acidic [tris(pentafluorophenyl)phosphine]gold hexafluoroantimonate [P(C6F5)3AuSbF6] in nitromethane (MeNO2) preferably gives 1‐indanones whereas [(ortho‐biphenyl)di(tert‐butyl)phosphine]gold triflimide [P(tBu)2(o‐biphenyl)AuNTf2] in dichloroethane tends to form 2‐indanone derivatives. For 2‐indanone products, we isolated two indenyl methyl ethers for deuterium labeling analyses, providing evidence for π‐alkyne activation.magnified image
Systematic Comparison of Peptidic Proteasome Inhibitors Highlights the α‐Ketoamide Electrophile as an Auspicious Reversible Lead Motif
Authors: Stein Martin L. , Cui Haissi , Beck Philipp , Dubiella Christian , Voss Constantin , Krüger Achim , Schmidt Boris , Groll Michael 
Published: January 2014

AbstractThe ubiquitin–proteasome system (UPS) has been successfully targeted by both academia and the pharmaceutical industry for oncological and immunological applications. Typical proteasome inhibitors are based on a peptidic backbone endowed with an electrophilic C‐terminus by which they react with the active proteolytic sites. Although the peptide moiety has attracted much attention in terms of subunit selectivity, the target specificity and biological stability of the compounds are largely determined by the reactive warheads. In this study, we have carried out a systematic investigation of described electrophiles by a combination of in vitro, in vivo, and structural methods in order to disclose the implications of altered functionality and chemical reactivity. Thereby, we were able to introduce and characterize the class of α‐ketoamides as the most potent reversible inhibitors with possible applications for the therapy of solid tumors as well as autoimmune disorders.
Whole Blood Gene Expression Profiling Predicts Therapeutic Response at Six Months in Patients With Polyarticular Juvenile Idiopathic Arthritis
Authors: Jiang Kaiyu , Sawle Ashley D. , Frank M. Barton , Chen Yanmin , Wallace Carol A. , Jarvis James N. 
Published: January 2014

ObjectiveTo determine whether gene expression profiles identified in peripheral whole blood samples could be used to determine therapeutic outcome in a cohort of children with newly diagnosed polyarticular juvenile idiopathic arthritis (JIA).MethodsWhole blood samples from the Trial of Early Aggressive Therapy (TREAT) in JIA patients were analyzed on Illumina microarrays, and differential gene expression was compared to expression in healthy controls. Microarray results were validated by real‐time quantitative polymerase chain reaction in an independent cohort of samples. Pathway analysis software was used to characterize gene expression profiles. Support vector machines were used to develop predictive models for different patient classes.ResultsDifferential gene expression profiles for rheumatoid factor (RF)–positive and RF‐negative patients were remarkably similar. Pathway analysis revealed a broad range of affected pathways, consistent with current mechanistic theories. Modeling showed that the prognosis at 6 months was strongly linked to gene expression at presentation, irrespective of treatment.ConclusionGene expression is linked to therapeutic outcome, and gene expression in the peripheral blood may be a suitable target for a prognostic test.
Dauerhaftes Brettschichtholz aus acetylierter Radiata Kiefer
Authors: Frese Matthias , Blaß Hans Joachim 
Published: January 2014

AbstractSeit dem Jahr 2007 ist modifizierte Radiata Kiefer auf dem Markt verfügbar. Gegenüber unbehandelter Radiata Kiefer sind deren Dauerhaftigkeit und Formstabilität mit einem patentierten Acetylierungsverfahren verbessert. Die auf diese Weise modifizierte Radiata Kiefer ist eine Alternative zu dauerhaften Tropenhölzern und eignet sich in Form von Brettschichtholz für frei bewitterte tragende Holzkonstruktionen. Das belegen erste realisierte Brückenbauwerke. Der Aufsatz berichtet über die Ergebnisse einer Forschungsarbeit, in der die wissenschaftliche Basis für eine in Deutschland zukünftig geltende baurechtliche Regelung von Brettschichtholz aus acetylierter Radiata Kiefer geschaffen wurde. Diese Arbeit umfasst experimentelle und numerische Untersuchungen zur Biegefestigkeit von Brettschichtholz aus acetylierter Radiata Kiefer und zahlreiche Versuche mit Verbindungsmitteln, auf deren Grundlage differenzierte Brettschichtholz‐Festigkeitsklassen entwickelt bzw. Kennwerte für die Bemessung von stiftförmigen Verbindungsmitteln hergeleitet wurden. Der Aufsatz zeigt Möglichkeiten und Grenzen auf, die bei der Bemessung von tragenden Bauteilen aus Brettschichtholz aus acetylierter Radiata Kiefer zu erwarten sind.Durabel timber structures made of acetylated Radiata pineAcetylated Radiata pine is available in the marked since 2007. Compared to the untreated wood, it has an improved durability and dimensional stability due to a patented acetylation process. Acetylated Radiata pine is, therefore, an alternative to durable tropical woods and is suitable for timber structures exposed to weather. The first bridge constructions made out of acetylated Radiata pine and without structural cover give proof of this. The article reports results of a research project that created the scientific basis for a future building regulation in Germany of glulam made out of acetylated Radiata pine. The article covers experimental and numerical investigations of the bending strength of glulam of acetylated Radiata pine and numerous tests with dowel‐type fasteners. The results obtained are the basis for specific glulam strength classes as well as characteristic values for the embedding strength and for the withdrawal parameter of self‐tapping screws. The article aims at showing possibilities and limits regarding structural design with glulam made out of acetylated Radiata pine.
Diagnostic performance of plasma biomarkers in patients with acute intestinal ischaemia
Authors: Matsumoto S , Sekine K , Funaoka H , Yamazaki M , Shimizu M , Hayashida K , Kitano M 
Published: January 2014

AbstractBackgroundThe aim of this study was to evaluate the use of intestinal fatty acid binding protein (I-FABP) and traditional biomarkers in the early diagnosis of acute intestinal ischaemia of different causes.MethodsI-FABP, white blood cell (WBC) count, C-reactive protein, base deficit, lactate, lactate dehydrogenase, aspartate aminotransferase, creatine kinase and D-dimer were measured prospectively in consecutive patients suspected of having acute intestinal ischaemia. Biomarker levels were compared in patients with vascular and non-vascular ischaemia.ResultsTwo hundred and eight patients with a clinical suspicion of acute intestinal ischaemia were enrolled. Vascular intestinal ischaemia was diagnosed in 24 patients (11·5 per cent), non-vascular ischaemia in 62 (29·8 per cent) and non-ischaemic disease in 122 (58·7 per cent). The levels of most biomarkers (except WBC count and creatine kinase) were significantly higher in the vascular ischaemia group than in the other groups (P &lt; 0·010). However, none of the biomarker levels differed between patients with non-vascular intestinal ischaemia and those with non-ischaemic disease. Receiver operating characteristic (ROC) curve analysis suggested that I-FABP was best at diagnosing vascular intestinal ischaemia (area under the curve 0·88).ConclusionSerum biomarkers may be useful in the diagnosis of vascular, but not non-vascular, intestinal ischaemia. Among them, I-FABP shows promise for detecting vascular ischaemia.
Feasibility and safety of a virtual 3‐Fr sheathless‐guiding system for percutaneous coronary intervention
Authors: Tonomura Daisuke , Shimada Yoshihisa , Yano Kentaro , Ito Kazato , Takehara Kosuke , Kino Naoto , Furubayashi Keiichi , Kurotobi Toshiya , Tsuchida Takao , Fukumoto Hitoshi 
Published: January 2014

ObjectivesTo evaluate the feasibility and safety of a virtual 3‐Fr system [5‐Fr sheathless‐guiding catheter (GC)] for percutaneous coronary intervention (PCI).BackgroundThe use of miniaturized devices for PCI is gaining popularity because of increased patient comfort and decreased risk of access site complications.MethodsFrom July 2010 to December 2012, consecutive patients who underwent elective PCI (planned or ad hoc PCI) at our hospital were enrolled. PCI using the virtual 3‐Fr system was attempted as our initial strategy, unless a 6‐Fr or larger GC was considered to be suitable [lesions with heavy calcification, large (>2 mm) side branches, or chronic total occlusion].ResultsFive hundred sixty‐six patients underwent elective PCI during the study period, and 132 patients who met the criteria underwent PCI using the virtual 3‐Fr system. Procedures using the virtual 3‐Fr system were successful in 126 patients (95%); 111 (84%) were performed using the transradial approach, 110 (83%) were ad hoc procedures, and 45 (31%) were complex coronary lesions (type B2 or C). Six patients required conversion to a conventional 5‐ or 6‐Fr sheath and catheter system. No intraoperative complications occurred, and radial artery patency was achieved in all patients who underwent transradial procedures.ConclusionsPCI using the virtual 3‐Fr system is a feasible and viable alternative to conventional procedures that use a sheath and GC in appropriately selected patients. This small‐caliber system may minimize endovascular trauma, particularly during transradial coronary procedures. © 2014 Wiley Periodicals, Inc.
Contribution of Raman Spectroscopy to In Situ Monitoring of a High‐Impact Polystyrene Process
Authors: Brun Nadège , Chevrel Marie‐Claire , Falk Laurent , Hoppe Sandrine , Durand Alain , Chapron David , Bourson Patrice 
Published: January 2014

AbstractA high‐impact polystyrene (HIPS) process has been studied using Raman spectroscopy as a monitoring technique for the first time. Thermal polymerization of styrene was carried out in the presence of polybutadiene. A Raman probe with a short focal distance, immersed into the reaction medium, allowed in situ monitoring of styrene consumption over the whole reaction progress. A Raman probe with a long focal distance set outside the glass reactor was applied to detect phase separation and phase inversion. Finally, coupling Raman spectroscopy and flow rheometry into a single experimental setup allowed in situ monitoring of both phase behavior and viscosity variation during the HIPS process. Results obtained from Raman spectroscopy were correlated to those from laser granulometry and gravimetric analysis.
Quench Pool Boiling with Temporary Crystalline Enhancers
Authors: Ladizhensky Izhak , Korin Eli , Mazor Gedalia , Nemirovsky Dmitry , Goldkin Evgeny 
Published: January 2014

AbstractIn some industrial activities, the use of permanent heat transfer enhancements such as metal coating, pins, and grooves in cryogenic treatment is quite problematic. Such permanent heat transfer enhancers were replaced with temporary enhancers made of different crystalline materials, here focusing on NaCl, MgSO4·7H2O, CaCl2·2H2O, and C6H5Na3O7·2H2O, which were used during quenching of the sample in the cryogenic liquid, i.e., nitrogen. The time required for sample cooling until the liquid nitrogen saturation temperature is reached decreases significantly when a crystalline coating is applied. The dependence of the cooling time on temporary coating creation parameters such as solution concentration, initial temperature of the sample, and solution spreading time is discussed.
A New Approach for the Photosynthetic Antenna–Reaction Center Complex with a Model Organized Around an s‐Triazine Linker
Authors: Kuhri Susanne , Charalambidis Georgios , Angaridis Panagiotis A. , Lazarides Theodore , Pagona Georgia , Tagmatarchis Nikos , Coutsolelos Athanassios G. , Guldi Dirk M. 
Published: January 2014

AbstractTwo new artificial mimics of the photosynthetic antenna‐reaction center complex have been designed and synthesized (BDP‐H2P‐C60 and BDP‐ZnP‐C60). The resulting electron‐donor/acceptor conjugates contain a porphyrin (either in its free‐base form (H2P) or as Zn‐metalated complex (ZnP)), a boron dipyrrin (BDP), and a fulleropyrrolidine possessing, as substituent of the pyrrolidine nitrogen, an ethylene glycol chain terminating in an amino group C60‐X‐NH2 (X=spacer). In both cases, the three different components were connected by s‐triazine through stepwise substitution reactions of cyanuric chloride. In addition to the facile synthesis, the star‐type arrangement of the three photo‐ and redox‐active components around the central s‐triazine unit permits direct interaction between one another, in contrast to reported examples in which the three components are arranged in a linear fashion. The energy‐ and electron‐transfer properties of the resulting electron‐donor/acceptor conjugates were investigated by using UV/Vis absorption and emission spectroscopy, cyclic voltammetry, and femtosecond transient absorption spectroscopy. Comparison of the absorption spectra and cyclic voltammograms of BDP‐H2P‐C60 and BDP‐ZnP‐C60 with those of BDP‐H2P, BDP‐ZnP and BDP‐C60, which were used as references, showed that the spectroscopic and electrochemical properties of the individual constituents are basically retained, although some appreciable shifts in terms of absorption indicate some interactions in the ground state. Fluorescence lifetime measurements and transient absorption experiments helped to elucidate the antenna function of BDP, which upon selective excitation undergoes a rapid and efficient energy transfer from BDP to H2P or ZnP. This is then followed by an electron transfer to C60, yielding the formation of the singlet charge‐separated states, namely BDP‐H2P.+‐C60.− and BDP‐ZnP.+‐C60.−. As such, the sequence of energy transfer and electron transfer in the present models mimics the events of natural photosynthesis.
Phenylene‐Coated Magnetic Nanoparticles that Boost Aqueous Asymmetric Transfer Hydrogenation Reactions
Authors: Gao Xiaoshuang , Liu Rui , Zhang Dacheng , Wu Meng , Cheng Tanyu , Liu Guohua 
Published: January 2014

AbstractPhenylene‐coated organorhodium‐functionalized magnetic nanoparticles are developed through co‐condensation of chiral 4‐(trimethoxysilyl)ethyl)phenylsulfonyl‐1,2‐diphenylethylene‐diamine and 1,4‐bis(triethyoxysilyl)benzene onto Fe3O4 followed complexation with [{Cp*RhCl2}2]. This magnetic catalyst exhibits excellent catalytic activity and high enantioselectivity in asymmetric transfer hydrogenation in aqueous medium. Such activity is attributed to the high hydrophobicity and the confined nature of the chiral organorhodium catalyst. The magnetic catalyst can be easily recovered by using a small external magnet and it can be reused for at least 10 times without loss of its catalytic activity. This characteristic makes it an attractive catalyst for environmentally friendly organic syntheses.
Polytwistane
Authors: Barua Shiblee R. , Quanz Henrik , Olbrich Martin , Schreiner Peter R. , Trauner Dirk , Allen Wesley D. 
Published: January 2014

AbstractTwistane, C10H16, is a classic D2‐symmetric chiral hydrocarbon that has been studied for decades due to its fascinating stereochemical and thermodynamic properties. Here we propose and analyze in detail the contiguous linear extension of twistane with ethano (ethane‐1,2‐diyl) bridges to create a new chiral, C2‐symmetric hydrocarbon nanotube called polytwistane. Polytwistane, (CH)n, has the same molecular formula as polyacetylene but is composed purely of C(sp3)H units, all of which are chemically equivalent. The polytwistane nanotube has the smallest inner diameter (2.6 Å) of hydrocarbons considered to date. A rigorous topological analysis of idealized polytwistane and a C236H242 prototype optimized by B3LYP density functional theory reveals that the polymer has a nonrepeating, alternating σ‐helix, with an irrational periodicity parameter and an instantaneous rise (or lead) angle near 15 °. A theoretical analysis utilizing homodesmotic equations and explicit computations as high as CCSD(T)/cc‐pVQZ yields the enthalpies of formation ${{\rm{\Delta }}_f H_0^ \circ }$(twistane)=−1.7 kcal mol−1 and ${{\rm{\Delta }}_f H_0^ \circ }$(polytwistane)= +1.28 kcal (mol CH)−1, demonstrating that the hypothetical formation of polytwistane from acetylene is highly exothermic. Hence, polytwistane is synthetically viable both on thermodynamic grounds and also because no obvious pathways exist for its rearrangement to lower‐lying isomers. The present analysis should facilitate the preparation and characterization of this new chiral hydrocarbon nanotube.
Evolution of Actinyl Peroxide Clusters U28 in Dilute Electrolyte Solution: Exploring the Transition from Simple Ions to Macroionic Assemblies
Authors: Li Dong , Simotwo Silas , Nyman May , Liu Tianbo 
Published: January 2014

AbstractActinyl peroxide clusters, a unique class of uranyl‐containing nanoclusters discovered in recent years, are crucial intermediates between the (UO2)2+ aqua‐ion monomer and bulk uranyl minerals. Herein, two actinyl polyoxometalate nanoclusters of Cs15[(Ta(O2)4)Cs4K12(UO2(O2)1.5)28]⋅20 H2O (CsKU28) and Na6K9[(Ta(O2)4)Rb4Na12(UO2(O2)1.5)28]⋅20 H2O (RbNaU28) were synthesized by incorporating a central Ta(O2)43− anion that templates a hollow shell of 28 uranyl peroxide polyhedra. When dissolved in aqueous solutions with additional electrolytes, those 1.8 nm‐size macroanions self‐assembled into spherical, hollow, blackberry‐type supramolecular structures, as was characterized by laser‐light scattering (LLS) and TEM techniques. These clusters are the smallest macroions reported to date that form blackberry structures in solution, therefore, can be treated as valuable models for investigating the transition from simple ions to macroions. Kinetic studies showed an unusually long lag phase in the initial self‐assembly process, which is followed by a rapid formation of the blackberry structures in solution. The small cluster size and high surface‐charge density are essential in regulating the supramolecular structure formation, as was shown from the high activation energy barrier of 51.2±2 kJ mol−1. Different countercations were introduced into the system to investigate the effect of ion binding to the length of the lag phase. The current research provides yet another scale of self‐assembly of uranyl peroxide complexes in aqueous media.
Oxidation of Benzyl Alcohol and Carbon Monoxide Using Gold Nanoparticles Supported on MnO2 Nanowire Microspheres
Authors: Alhumaimess Mosaed , Lin Zhongjie , He Qian , Lu Li , Dimitratos Nickolaos , Dummer Nicholas F. , Conte Marco , Taylor Stuart H. , Bartley Jonathan K. , Kiely Christopher J. , Hutchings Graham J. 
Published: January 2014

AbstractMnO2 was synthesised as a catalyst support material using a hydrothermal method. This involved reacting MnSO4⋅H2O and (NH4)2S2O8 at 120 °C for a range of crystallisation times, which affords control over the morphology and phase composition of the MnO2 formed. Gold was deposited on these supports using sol‐immobilisation, impregnation and deposition precipitation methods, and the resultant materials were used for the oxidation of benzyl alcohol and carbon monoxide. The effect of the support morphology on the dispersion of the gold nanoparticles and the consequent effect on the catalytic performance is described and discussed.
Enantioselective Copper(I/II)‐Catalyzed Conjugate Addition of Nitro Esters to β,γ‐Unsaturated α‐Ketoesters
Authors: Zhang Sheng , Xu Kun , Guo Fengfeng , Hu Yanbin , Zha Zhenggen , Wang Zhiyong 
Published: January 2014

AbstractA highly enantioselective Michael addition of nitroacetates to β,γ‐unsaturated α‐ketoesters was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields with up to 99 % ee. With these densely functionalized products, the chiral cyclic nitrones, which are important synthetic intermediates, can be obtained in one step.
Strongly Luminous Tetranuclear Gold(I) Complexes Supported by Tetraphosphine Ligands, meso‐ or rac‐Bis[(diphenylphosphinomethyl)phenylphosphino]methane
Authors: Tanase Tomoaki , Otaki Risa , Nishida Tomoko , Takenaka Hiroe , Takemura Yukie , Kure Bunsho , Nakajima Takayuki , Kitagawa Yasutaka , Tsubomura Taro 
Published: January 2014

AbstractA series of tetragold(I) complexes supported by tetraphosphine ligands, meso‐ and rac‐bis[(diphenylphosphinomethyl)phenylphosphino]methane (meso‐ and rac‐dpmppm) were synthesized and characterized to show that the tetranuclear AuI alignment varies depending on syn‐ and anti‐arrangements of the two dpmppm ligands with respect to the metal chain. The structures of syn‐[Au4(meso‐dpmppm)2X]X′3 (X=Cl; X′=Cl (4 a), PF6 (4 b), BF4 (4 c)) and syn‐[Au4(meso‐dpmppm)2]X4 (X=PF6 (4 d), BF4 (4 e), TfO (4 f); TfO=triflate) involved a bent tetragold(I) core with a counter anion X incorporated into the bent pocket. Complexes anti‐[Au4(meso‐dpmppm)2]X4 (X=PF6 (5 d), BF4 (5 e), TfO (5 f)) contain a linearly ordered Au4 string and complexes syn‐[Au4(rac‐dpmppm)2X2]X′2 (X=Cl, X′=Cl (6 a), PF6 (6 b), BF4 (6 c)) and syn‐[Au4(rac‐dpmppm)2]X4 (X=PF6 (6 d), BF4 (6 e), TfO (6 f)) consist of a zigzag tetragold(I) chain supported by the two syn‐arranged rac‐dpmppm ligands. Complexes 4 d–f, 5 d–f, and 6 d–f with non‐coordinative large anions are strongly luminescent in the solid state (λmax=475–515 nm, Φ=0.67–0.85) and in acetonitrile (λmax=491–520 nm, Φ=0.33–0.97); the emission was assigned to phosphorescence from 3[dσ*σ*σ*pσσσ] excited state of the Au4 centers on the basis of DFT calculations as well as the long lifetime (a few μs). The emission energy is predominantly determined by the HOMO and LUMO characters of the Au4 centers, which depend on the bent (4), linear (5), and zigzag (6) alignments. The strong emissions in acetonitrile were quenched by chloride anions through simultaneous dynamic and static quenching processes, in which static binding of chloride ions to the Au4 excited species should be the most effective. The present study demonstrates that the structures of linear tetranuclear gold(I) chains can be modified by utilizing the stereoisomeric tetraphosphines, meso‐ and rac‐dpmppm, which may lead to fine tuning of the strongly luminescent properties intrinsic to the AuI4 cluster centers.
Synthesis of Heterodinuclear Hemisalen Complexes on a Hexaarylbenzene Scaffold and their Application for the Cross‐Pinacol Coupling Reaction
Authors: Miyasaka Akihiro , Amaya Toru , Hirao Toshikazu 
Published: January 2014

AbstractIntermolecular cross‐pinacol coupling reaction between aliphatic and aromatic aldehydes by using heterodinuclear hemisalen complexes 1cis with vanadium(V) and titanium(IV) on a hexaarylbenzene scaffold is reported. Our ligand design is based on the individual activation of two aldehydes by vanadium and titanium, which are positioned with a suitable space on the rigid scaffold. Ligands such as 1cis were synthesized by Diels–Alder addition and decarbonylation reaction, followed by condensation of dialdehyde 3cis with various aminophenols. The influence of the substituents on the ligands on the pinacol coupling reaction was investigated. As a result, the reductive coupling reaction between aliphatic and aromatic aldehydes by using a catalytic amount of 1cis in the presence of Me3SiCl and Zn provided the corresponding cross‐coupled 1,2‐diol in good yields with high cross‐selectivity.