bluuebunny/crossref_metadata_2025_split huggingface dataset:
Power spectrum analysis of ionospheric fluctuations with the Murchison Widefield Array
Authors: Loi Shyeh Tjing , Trott Cathryn M. , Murphy Tara , Cairns Iver H. , Bell Martin , Hurley‐Walker Natasha , Morgan John , Lenc Emil , Offringa A. R. , Feng L. , Hancock P. J. , Kaplan D. L. , Kudryavtseva N. , Bernardi G. , Bowman J. D. , Briggs F. , Cappallo R. J. , Corey B. E. , Deshpande A. A. , Emrich D. , Gaensler B. M. , Goeke R. , Greenhill L. J. , Hazelton B. J. , Johnston‐Hollitt M. , Kasper J. C. , Kratzenberg E. , Lonsdale C. J. , Lynch M. J. , McWhirter S. R. , Mitchell D. A. , Morales M. F. , Morgan E. , Oberoi D. , Ord S. M. , Prabu T. , Rogers A. E. E. , Roshi A. , Shankar N. Udaya , Srivani K. S. , Subrahmanyan R. , Tingay S. J. , Waterson M. , Wayth R. B. , Webster R. L. , Whitney A. R. , Williams A. , Williams C. L. 
Published: June 2015

AbstractLow‐frequency, wide field‐of‐view (FOV) radio telescopes such as the Murchison Widefield Array (MWA) enable the ionosphere to be sampled at high spatial completeness. We present the results of the first power spectrum analysis of ionospheric fluctuations in MWA data, where we examined the position offsets of radio sources appearing in two data sets. The refractive shifts in the positions of celestial sources are proportional to spatial gradients in the electron column density transverse to the line of sight. These can be used to probe plasma structures and waves in the ionosphere. The regional (10–100 km) scales probed by the MWA, determined by the size of its FOV and the spatial density of radio sources (typically thousands in a single FOV), complement the global (100–1000 km) scales of GPS studies and local (0.01–1 km) scales of radar scattering measurements. Our data exhibit a range of complex structures and waves. Some fluctuations have the characteristics of traveling ionospheric disturbances, while others take the form of narrow, slowly drifting bands aligned along the Earth's magnetic field.
Dexamethasone suppresses allergic rhinitis and amplifies CD4+Foxp3+ regulatory T cells in vitro
Authors: Wang Weihua , Jiang Tingting , Zhu Zhenghua , Cui Jiawen , Zhu Liwei , Ma Zhaoxin 
Published: June 2015

BackgroundGlucocorticosteroids (GCs) are highly effective in mitigating allergic inflammation. In this study, we investigate the effects of dexamethasone (DEX) on regulatory T cells (Tregs) in a murine model of allergic rhinitis (AR).MethodsBALB/c mice were sensitized to ovalbumin (OVA) followed by intranasal OVA challenge. Mice in the treatment group received DEX by intraperitoneal injection (5 mg/kg/day) 1 hour before the OVA challenge. Further, CD4+CD25− T cells from the spleens were cultured in presence of DEX. The effects of DEX on CD4+Foxp3+ T cells were then assessed in vivo as well as in vitro.ResultsFrequencies of sneezing and scratching decreased significantly in the DEX‐treated group compared to that in the OVA group. Histopathological analyses showed that DEX restored the destroyed and discontinuous ciliated epithelium of the nasal mucosa in the OVA group. Moreover, DEX inhibited the production of interleukin (IL)‐4, IL‐5, and IL‐13 in the nasal cavity lavage fluid in this group. We also observed a significant increase in the percentage of CD4+Foxp3+ T cells in the OVA group. In vivo, DEX treatment significantly decreased the number of CD4+Foxp3+ T cells. However, in vitro, the proportion of these cells increased in the presence of DEX. Furthermore, the number of late stage apoptotic CD4+ T cells was also significantly increased upon exposure to DEX.ConclusionDEX therapy effectively suppresses AR symptoms, but does not result in the expected increase in the frequency of Tregs in vivo. Thus, whether GCs exert immunosuppressive effects by influencing the number of Tregs remains unresolved.
Regio‐ and Stereoselective Conjugate Addition of Aldehydes to β‐Tosyl Enones under the Catalysis of a Binaphthyl‐Modified Chiral Amine
Authors: Kano Taichi , Sugimoto Hisashi , Maruyama Hiroki , Maruoka Keiji 
Published: June 2015

AbstractA simple axially chiral amine catalyst promoted the regio‐, diastereo‐, and enantioselective conjugate addition of aldehydes to β‐tosyl enones, which serve as ynone surrogates. The adducts were readily converted by treatment with L‐selectride into less accessible enones with a γ stereogenic center. Such compounds cannot be prepared through the amine‐catalyzed conjugate addition of aldehydes to ynones. The obtained enones underwent further conjugate addition of diorganozinc compounds in the presence of a copper catalyst.
Radicals Are Required for Thiol Etching of Gold Particles
Authors: Dreier Timothy A. , Ackerson Christopher J. 
Published: June 2015

AbstractEtching of gold with an excess of thiol ligand is used in both synthesis and analysis of gold particles. Mechanistically, the process of etching gold with excess thiol is unclear. Previous studies have obliquely considered the role of oxygen in thiolate etching of gold. Herein, we show that oxygen or a radical initiator is a necessary component for efficient etching of gold by thiolates. Attenuation of the etching process by radical scavengers in the presence of oxygen, and the restoration of activity by radical initiators under inert atmosphere, strongly implicate the oxygen radical. These data led us to propose an atomistic mechanism in which the oxygen radical initiates the etching process.
β,β‐Diborylated Subporphyrinato Boron(III) Complexes as Useful Synthetic Precursors
Authors: Kitano Masaaki , Okuda Yasuhiro , Tsurumaki Eiji , Tanaka Takayuki , Yorimitsu Hideki , Osuka Atsuhiro 
Published: June 2015

AbstractIridium‐catalyzed borylation of B‐aryl meso‐free subporphyrinato boron(III) complexes (hereinafter referred to simply as subporphyrins) with bis(pinacolato)diboron gave 2,13‐diborylated subporphyrins regioselectively, which served as promising synthetic precursors for 2,13‐diarylated subporphyrins and doubly β‐to‐β 1,3‐butadiyne‐bridged subporphyrin dimers. 2,13‐Diarylated subporphyrins display perturbed absorption spectra, depending upon the β‐aryl substituents. Doubly 1,3‐butadiyne‐bridged syn and anti subporphyrin dimers thus prepared exhibit differently altered absorption spectra with split Soret‐like bands, which have been accounted for in terms of exciton coupling.
Force Spectroscopy of Metal–Crown Ether Multivalency: Effect of Local Environments on Energy Landscape and Sensing Kinetics
Authors: Kuo Ting‐Yang , Tseng Wei‐Hsiang , Chen Chun‐hsien 
Published: June 2015

AbstractSandwich complexation involving alkali or alkaline‐earth metals, multivalency, and effects associated with local environments is widely encountered in biological and synthetic systems yet the mechanic properties remain unexplored. Herein, AFM (atomic force microscopy)‐based single‐molecule force spectroscopy is employed to investigate a classical model of Mn+[15C5]2, a metal cation hosted jointly by two 15‐crown‐5 moieties immobilized on both the substrate and the AFM tip. Factors reportedly promoting the recognition performance are examined. The rupture force required to break apart Mn+[15C5]2 is found to be in the order of tens of pico‐Newton, e.g., fβ=31 pN for K+[15C5]2. The presence of a second functional group, carboxylate, confers K+[15C5]2 with a longer lifetime (from 13 to 16 ms), faster association (from 0.4 to 1.3×106 M−1 s−1), and slower dissociation (from 77 to 62 s−1). The effect of local environments is significant on association yet less critical on dissociation pathways.
Doping Effects in Cluster‐Mediated Bond Activation
Authors: Schwarz Helmut 
Published: June 2015

AbstractGas‐phase investigations of judiciously doped oxide clusters permit to address fundamental challenges related to, for example, the low‐temperature oxidation of CO or the selective conversion of hydrocarbons. Modifying the size and composition of a free cluster in a controlled way enables the modification of local charge effects and of spin states, and spectroscopic studies in combination with computational work help to identify the active site of a catalyst and to unravel mechanistic details. Also, the interplay of the support material with the reactive part of a composite catalyst cluster can be addressed. Examples will be presented demonstrating how and why the gas‐phase reactivities of heteronuclear clusters, in comparison with their homonuclear counterparts, toward small, generally rather inert molecules can be increased, decreased, or not significantly affected.
Photocontrolled Reversible Conversion of Nanotube and Nanoparticle Mediated by β‐Cyclodextrin Dimers
Authors: Sun He‐Lue , Chen Yong , Zhao Jin , Liu Yu 
Published: June 2015

AbstractA photochemically interconvertible supramolecular nanotube–nanoparticle system was constructed through secondary assembling of self‐aggregates of amphiphilic porphyrin derivatives mediated by trans‐ and cis‐azobenzene‐bridged bis(permethyl‐β‐cyclodextrin). Significantly, these nanotubes and nanoparticles were able to interconvert upon irradiation at different wavelengths, and this photocontrolled morphological conversion is reversible and recyclable for tens of times, which will provide a feasible and convenient way to construct the ordered nanostructure with various morphologies that can be smartly controlled by the environmentally benign external stimulus.
Ruthenium Clusters on Carbon Nanofibers for Formic Acid Decomposition: Effect of Doping the Support with Nitrogen
Authors: Zacharska Monika , Podyacheva Olga Yu. , Kibis Lidiya S. , Boronin Andrey I. , Senkovskiy Boris V. , Gerasimov Evgeny Yu. , Taran Oxana P. , Ayusheev Artemiy B. , Parmon Valentin N. , Leahy J. J. , Bulushev Dmitri A. 
Published: June 2015

AbstractThe catalytic properties of 1 wt % Ru catalysts with the same mean Ru cluster size of 1.4–1.5 nm supported on herringbone‐type carbon nanofibers with different N contents were compared for H2 production from formic acid decomposition. The Ru catalyst on the support with 6.8 wt % N gave a 1.5–2 times higher activity for the dehydrogenation reaction (CO2, H2) than the catalyst on the undoped support. The activity in the dehydration reaction (CO, H2O) was the same. As a result, the selectivity to H2 increased significantly from 83 to 92 % with N‐doping, and the activation energies for both reactions were close (55–58 kJ mol−1). The improvement could be explained by the presence of Ru clusters stabilized by pyridinic N located on the open edges of the external surface of the carbon nanofibers. This N may activate formic acid by the formation of an adduct (>NH+HCOO−) followed by its dehydrogenation on the adjacent Ru clusters.
Cu/Fe‐Cocatalyzed Formation of β‐Ketophosphonates by a Domino Knoevenagel–Decarboxylation–Oxyphosphorylation Sequence from Aromatic Aldehydes and H‐Phosphonates
Authors: Zhou Mingxin , Zhou Yao , Song Qiuling 
Published: June 2015

AbstractA domino Knoevenagel–decarboxylation–alkene difunctionalization sequence has been developed for the conversion of benzaldehydes into β‐ketophosphonates, catalyzed by a cooperative Cu/Fe system, whereby CP and CO bonds are formed simultaneously in a one‐pot reaction. The reaction proceeds in good yields and with a broad substrate scope and environmentally benign conditions.
ChemInform Abstract: Investigation of a Naked Ag7 Cluster: Configurations and Spectral Characteristics.
Authors: Xu Shuhong , Wang Zhaochong , Wang Chunlei , Wang Zhuyuan , Cui Yiping 
Published: June 2015

AbstractDFT calculations show that the most stable Ag7 cluster is a pentagonal bipyramid, whereas synthesized Ag7 clusters are planar due to interactions with ligands as revealed by Raman and UV/VIS spectroscopy.
ChemInform Abstract: Synthesis of Li3V2(PO4)3/C for Use as the Cathode Material in Lithium Ion Batteries Using Polyvinylidene Fluoride as the Source of Carbon.
Authors: Li Lingfang , Fan Changling , Zhang Xiang , Zeng Taotao , Zhang Weihua , Han Shaochang 
Published: June 2015

AbstractThe cathode material of title is prepared by a hybrid sol—gel method from an aqueous 1:3:1.5:3:0.1 mixture of V2O5, Li2CO3, NH4H2PO4, H2C2O4, and cetyltrimethyl ammonium bromide using polyvinylidene fluoride as the carbon source (sintering at 700 °C for 10 h under Ar).
ChemInform Abstract: The High‐Pressure Cadmium Borate Cd6B22O39·H2O.
Authors: Sohr Gerhard , Ciaghi Nina , Wurst Klaus , Huppertz Hubert 
Published: June 2015

AbstractColorless crystals of the new title compound are synthesized from a 1:2 molar mixture of CdO and partially hydrolyzed B2O3 using a Walker‐type multianvil apparatus (Pt capsule, 4.7 GPa, 1000 °C, 10 min).
ChemInform Abstract: Air‐Stable Palladium(0) Phosphine Sulfide Catalysts for Ullmann‐Type C—N and C—O Coupling Reactions.
Authors: Majumder Arpi , Gupta Ragini , Mandal Mrinmay , Babu Madhu , Chakraborty Debashis 
Published: June 2015

AbstractPhenyl bromide as reaction partner in amination and etherification gives similar (amination) or lower (etherification) yields at longer reaction times.
ChemInform Abstract: Asymmetric Rhodium‐Catalyzed Addition of Thiols to Allenes: Synthesis of Branched Allylic Thioethers and Sulfones.
Authors: Pritzius Adrian B. , Breit Bernhard 
Published: June 2015

AbstractA new highly regio‐ and enantioselective hydrothiolation of terminal allenes is presented.
ChemInform Abstract: Zirconium‐Catalyzed Desymmetrization of Aminodialkenes and Aminodialkynes Through Enantioselective Hydroamination.
Authors: Manna Kuntal , Eedugurala Naresh , Sadow Aaron D. 
Published: June 2015

AbstractIn this zirconium‐catalyzed hydroamination, stereocenters resulting from C—N bond formation and desymmetrization of a prochiral quaternary center are independently controlled by the catalyst and reaction conditions.
ChemInform Abstract: Palladium‐Catalyzed, Ligand‐Free Suzuki Reaction in Water Using Aryl Fluorosulfates.
Authors: Liang Qiaobin , Xing Ping , Huang Zuogang , Dong Jiajia , Sharpless K. Barry , Li Xiaoxian , Jiang Biao 
Published: June 2015

AbstractEasily prepared aryl fluorosulfates are used as coupling partners in the Suzuki—Miyaura reaction.
ChemInform Abstract: Pd‐Catalyzed Intramolecular C—N Bond Cleavage, 1,4‐Migration, sp3 C—H Activation, and Heck Reaction: Four Controllable Diverse Pathways Depending on the Judicious Choice of the Base and Ligand.
Authors: Wang Min , Zhang Xiang , Zhuang Yu‐Xuan , Xu Yun‐He , Loh Teck‐Peng 
Published: June 2015

AbstractVinylacetamide derivatives having a N‐(o‐bromoaryl)methyl or N‐bromoallyl substituent are investigated in intramolecular Pd‐catalyzed reactions providing four different types of products.
ChemInform Abstract: Stereoselective Synthesis and Reactions of Secondary Alkyllithium Reagents Functionalized at the 3‐Position.
Authors: Moriya Kohei , Didier Dorian , Simon Meike , Hammann Jeffrey M. , Berionni Guillaume , Karaghiosoff Konstantin , Zipse Hendrik , Mayr Herbert , Knochel Paul 
Published: June 2015

AbstractIt is demonstrated that 3‐Tbs‐oxy‐substituted alkyllithium compounds can be generated in a stereoconvergent manner from the corresponding iodo‐compounds.
ChemInform Abstract: Nickel‐Catalyzed Allylation of α‐Amido Sulfones to Form Protected Homoallylic Amines.
Authors: Caputo Jill A. , Naodovic Marina , Weix Daniel J. 
Published: June 2015

AbstractN‐Boc‐ or N‐Cbz‐protected α‐amino sulfones are allylated with allyl acetate derivatives.
ChemInform Abstract: A Convenient Route to Tetraalkylammonium Perfluoroalkoxides from Hydrofluoroethers.
Authors: Jelier Benson J. , Howell Jon L. , Montgomery Craig D. , Leznoff Daniel B. , Friesen Chadron M. 
Published: June 2015

AbstractPerfluoroalkyl methyl ether acts as methylating reagent on tertiary aliphatic amines.
ChemInform Abstract: Microwave‐Ultrasound Simultaneous Irradiation: A Hybrid Technology Applied to Ring Closing Metathesis.
Authors: Sacco M. , Charnay C. , De Angelis F. , Radoiu M. , Lamaty F. , Martinez J. , Colacino E. 
Published: June 2015

AbstractA new hybrid microwave‐ and ultrasound‐assisted reactor is developed.
ChemInform Abstract: Iridium‐ and Rhodium‐Catalyzed C—H Activation and Formyl Alkynylation of Benzaldehydes under Chelation‐Assistance.
Authors: Wang He , Xie Fang , Qi Zisong , Li Xingwei 
Published: June 2015

AbstractA mild and efficient synthesis of ynones using Ir(III) or Rh(III) catalysis is presented.
ChemInform Abstract: α‐(N‐Sulfonyl)amino Amides from a Carbamoylsilane and N‐Sulfonylimine.
Authors: Tong Wenting , Liu Hui , Chen Jianxin 
Published: June 2015

AbstractThe addition of carbamoylsilane to N‐sulfonylimines offers a general and efficient route to the title compounds (III) and (V).
ChemInform Abstract: A Porphyrin‐Inspired Iron Catalyst for Asymmetric Epoxidation of Electron‐Deficient Olefins.
Authors: Dai Wen , Li Guosong , Chen Bo , Wang Lianyue , Gao Shuang 
Published: June 2015

AbstractThe title asymmetric epoxidation of di‐ and trisubstituted enones provides highly enantioenriched α,β—epoxyketones.
ChemInform Abstract: Nickel Oxide Nanoparticles: A Green and Recyclable Catalytic System for the Synthesis of Diindolyloxindole Derivatives in Aqueous Medium.
Authors: Nasseri Mohammad Ali , Ahrari Faezeh , Zakerinasab Batol 
Published: June 2015

AbstractAn efficient method for the synthesis of the title compounds under mild reaction conditions is developed.
ChemInform Abstract: Rhodium(III)‐Catalyzed C—H Activation and Intermolecular Annulation with Terminal Alkynes: From Indoles to Carbazoles.
Authors: Jia Jinlong , Shi Jingjing , Zhou Jie , Liu Xuelei , Song Yanling , Xu H. Eric , Yi Wei 
Published: June 2015

AbstractA series of N‐2‐pyrimidyl protected carbazoles (III) and (X) is readily prepared by a Rh‐catalyzed annulation of indoles (I) with terminal alkynes.
ChemInform Abstract: Rh(I)—Bisphosphine‐Catalyzed Asymmetric, Intermolecular Hydroheteroarylation of α‐Substituted Acrylate Derivatives.
Authors: Filloux Claire M. , Rovis Tomislav 
Published: June 2015

AbstractThe development of an asymmetric, intermolecular hydroheteroarylation reaction of α‐substituted acrylates with benzoxazoles is described.
ChemInform Abstract: Direct Construction of 2‐Alkylbenzo‐1,3‐azoles via C—H Activation of Alkanes for C—C and C—X (X: O, S) Bond Formation.
Authors: Yadav Arvind K. , Yadav Lal Dhar S. 
Published: June 2015

AbstractC‐2 alkylated benzo‐1,3‐thiazoles and ‐oxazoles are obtained by reaction of aryl isothiocyanates/isocyanates with simple alkanes in a catalytic, efficient, and cost‐effective manner.
ChemInform Abstract: Convenient and Highly Efficient Routes to 2H‐Chromene and 4‐Chromanone Derivatives: Iodine‐Promoted and p‐Toluenesulfonic Acid Catalyzed Cascade Cyclizations of Propynols.
Authors: Liang Yong‐Min , et al.  
Published: June 2015

AbstractEither conditions A) or B) can be used for all starting propynols to afford the desired benzopyran structures.
ChemInform Abstract: Rhodium(III)‐Catalyzed Vinylic C—H Activation: A Direct Route Toward Pyridinium Salts.
Authors: Luo Ching‐Zong , Jayakumar Jayachandran , Gandeepan Parthasarathy , Wu Yun‐Ching , Cheng Chien‐Hong 
Published: June 2015

AbstractHighly substituted pyridinium salts are synthesized via a multicomponent reaction of vinyl ketones/aldehydes, amines, and alkynes.
ChemInform Abstract: Design of New Hybrid Template by Linking Quinoline, Triazole and Dihydroquinoline Pharmacophoric Groups: A Greener Approach to Novel Polyazaheterocycles as Cytotoxic Agents.
Authors: Praveena Koduru Sri Shanthi , Shivaji Ramarao Edupuganti Veera Venkat , Murthy Nandula Yadagiri Sreenivasa , Akkenapally Surekha , Ganesh Kumar C. , Kapavarapu Ravikumar , Pal Sarbani 
Published: June 2015

AbstractA variety of new polyazaheterocycles (III) are synthesized via Cu(I)‐catalyzed azide‐alkyne cycloaddition reactions.
ChemInform Abstract: Organocatalytic Asymmetric Synthesis of Dihydroisoquinolinones via a One‐Pot Aza‐Henry—Hemiaminalization—Oxidation Sequence.
Authors: Hahn Robert , Jafari Ehsan , Raabe Gerhard , Enders Dieter 
Published: June 2015

AbstractThe products are obtained as single diastereomers with moderate to high enantiomeric excess.
ChemInform Abstract: Two Rearrangement Pathways in the Geminal Acylation of 2‐Methoxyoxazolidines Leading to Substituted 1,4‐Oxazines.
Authors: Moulins Jonathan R. , Hughes Jeremy A. , Doyle Lauren E. , Cameron T. Stanley , Burnell D. Jean 
Published: June 2015

AbstractLewis acid‐mediated geminal acylation of 2‐methoxyoxazolidines with five‐ or six‐membered acyloins followed by heterocyclization affords 1,4‐oxazines fused to cyclopentenone or cyclohexenone rings.
ChemInform Abstract: Copper(I)‐Catalyzed Enantioselective Nucleophilic Borylation of Aldehydes: An Efficient Route to Enantiomerically Enriched α‐Alkoxyorganoboronate Esters.
Authors: Kubota Koji , Yamamoto Eiji , Ito Hajime 
Published: June 2015

AbstractUsing a copper(I)/DTBM‐SEGPHOS complex catalyst and MeOH as a proton source, the enantioselective nucleophilic borylation of aldehydes is achieved for the first time.
ChemInform Abstract: Iridium‐Catalyzed Silylation of Aryl C—H Bonds.
Authors: Cheng Chen , Hartwig John F. 
Published: June 2015

AbstractThe catalyst system under conditions A) is found to be optimal for the silylation of arenes, various hetarenes, and a broad spectrum of pharmaceutical agents such as the antidepressants mirtazapine (XX) and bupropion (XXII).
ChemInform Abstract: Synthesis of 1,2‐Dihydro‐2‐oxo‐4‐quinolinyl Phosphates from 2‐Acyl‐benzoic Acids.
Authors: He Xinhua , Aglio Tharcilla , Deschamps Jeffrey R. , Rai Rachita , Xue Fengtian 
Published: June 2015

AbstractA practical method to synthesize the title compounds starting from readily available starting materials is described.
ChemInform Abstract: Nucleophilic Cyclization of o‐Alkynylbenzamides Promoted by Iron(III) Chloride and Diorganyl Dichalcogenides: Synthesis of 4‐Organochalcogenyl‐1H‐isochromen‐1‐imines.
Authors: Neto Jose S. S. , Back Davi F. , Zeni Gilson 
Published: June 2015

AbstractA facile protocol for the reaction of o‐alkynylbenzamides with diorganyl dichalcogenides is presented.
2,2′‐Bis‐substituted Biphenyls by the Addition of Nucleophiles to Benzyne Followed by In Situ Oxidative Homocoupling
Authors: Sibbel Friederike , Daniliuc Constantin G. , Studer Armido 
Published: June 2015

AbstractThe paper describes the addition of Mg‐anilides and ‐thiolates to in situ generated benzyne with subsequent oxidative homocoupling of the adducts to give 2,2′‐bis‐substituted biphenyls in a one‐pot process. Oxidative C–C bond formation was best achieved with a Cu catalyst using O2 as oxidant. The sequence comprises two C–X and one C–C bond formation and the products were obtained in moderate yields. Some of the 2,2′‐bis‐substituted biphenyls have been characterized by X‐ray analysis.