bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: The Quantum Cutting of Tb3+ in Ca6Ln2Na2 (PO4)6F2 (Ln: Gd, La) under VUV—UV Excitation: With and Without Gd3+.
Authors: Xie Mubiao , Tao Ye , Huang Yan , Liang Hongbin , Su Qiang 
Published: January 2011

AbstractThe phosphors Ca6Gd2‐xTbxNa2 (PO4)6F2 show strong absorption in the vacuum UV (VUV) range and have intense emission upon 172 nm excitation, while Ca6La2‐xTbxNa2 (PO4)6F2 phosphors exhibit weaker absorption in the VUV range.
ChemInform Abstract: Facile Synthesis of Highly Active and Stable Pt—Ir/C Electrocatalysts for Oxygen Reduction and Liquid Fuel Oxidation Reaction.
Authors: Hwang Seung Jun , Yoo Sung Jong , Jeon Tae‐Yeol , Lee Kug‐Seung , Lim Tae‐Hoon , Sung Yung‐Eun , Kim Soo‐Kil 
Published: January 2011

AbstractPt—Ir/C electrocatalysts for applications in low‐temperature fuel cells are prepared from a mixture of carbon black, PtCl4, IrCl3, NaBH4, and cetyltrimethylammonium bromide in anhydrous EtOH, followed by heat treatment at 250 °C under Ar/5 vol.% H2 for 2 h.
ChemInform Abstract: Bi3In4S10 and Bi14.7In11.3S38: Two New Bismuth Sulfides with Interesting Bi—Bi Bonding.
Authors: Yin Wenlong , Mei Dajiang , Yao Jiyong , Fu Peizhen , Wu Yicheng 
Published: January 2011

AbstractBlack single crystals of compounds (III) and (IV) are prepared via a two‐step flux method and characterized by single crystal XRD and UV/VIS diffuse reflectance spectroscopy.
ChemInform Abstract: The New Ternary Pnictides Er12Ni30P21 and Er13Ni25As19: Crystal Structures and Magnetic Properties.
Authors: Oryshchyn Stepan , Babizhetskyy Volodymyr , Zhak Olga , Zelinska Mariya , Pivan Jean‐Yves , Duppel Viola , Simon Arndt , Kienle Lorenz 
Published: January 2011

AbstractThe new title compounds are prepared by reactions of stoichiometric mixtures of the elements (1100 °C for 3 d) followed by annealing at 1300—1500 °C for 48—72 h.
ChemInform Abstract: One‐Pot Asymmetric Cyclocarbohydroxylation Sequence for the Enantioselective Synthesis of Functionalized Cyclopentanes.
Authors: Raimondi Wilfried , Lettieri Gregory , Dulcere Jean‐Pierre , Bonne Damien , Rodriguez Jean 
Published: January 2011

AbstractA new method for the highly enantioselective synthesis of functionalized cyclopentanes bearing up to three stereogenic centers is developed.
ChemInform Abstract: Synthesis of 3‐Fluoroimidazo[1,2‐a]pyrimidines and 5‐Fluoroimidazo[2,1‐b][1,3]thiazoles via Heterocyclization of (N‐Heteroarylimino)trifluoropyruvates.
Authors: Rassukana Y. V. , Khomutnyk Y. Y. , Onys'ko P. P. , Sinitsa A. D. , Gakh A. A. 
Published: January 2011

AbstractA convenient approach to ring‐fluorinated fused imidazoles is given.
ChemInform Abstract: C(sp3)—C(sp3) Bond Breaking in Methylenecyclopropanes Involving a AuI/AuIII Catalytic Cycle.
Authors: Zhang Di‐Han , Dai Lun‐Zhi , Shi Min 
Published: January 2011

AbstractThe gold‐catalyzed diacetoxylation of methylenecyclopropanes proceeds under mild conditions providing in most cases the corresponding diacetoxylated products.
ChemInform Abstract: Room‐Temperature Deoxygenation of Epoxides with CO Catalyzed by Hydrotalcite‐Supported Gold Nanoparticles in Water.
Authors: Mitsudome Takato , Noujima Akifumi , Mikami Yusuke , Mizugaki Tomoo , Jitsukawa Koichiro , Kaneda Kiyotomi 
Published: January 2011

AbstractAn alternative green methodology for the catalytic deoxygenation of epoxides with hydrotalcite‐supported gold nanoparticles by using CO/H2O as reducing reagent is reported.
ChemInform Abstract: Practical Iron‐Catalyzed Allylations of Aryl Grignard Reagents.
Authors: Mayer Matthias , Czaplik Waldemar M. , Jacobi von Wangelin Axel 
Published: January 2011

AbstractGrignard compounds generated in situ from aryl bromides undergo a Fe(acac)3‐catalyzed reductive cross‐coupling reaction with allylic electrophiles.
ChemInform Abstract: Highly Modular P‐OP Ligands in Asymmetric Allylic Substitution.
Authors: Panossian Armen , Fernandez‐Perez Hector , Popa Dana , Vidal‐Ferran Anton 
Published: January 2011

AbstractA library of P‐OP ligands is prepared and used in Pd‐catalyzed allylic substitutions with C‐ and N‐nucleophiles.
ChemInform Abstract: A Palladium/Copper Bimetallic Catalytic System: Dramatic Improvement for Suzuki—Miyaura‐Type Direct C—H Arylation of Azoles with Arylboronic Acids.
Authors: Liu Bo , Qin Xurong , Li Kaizhi , Li Xiyu , Guo Qiang , Lan Jingbo , You Jingsong 
Published: January 2011

AbstractPalladium/copper bimetallic‐catalyzed Suzuki—Miyaura‐type coupling is disclosed for direct C—H arylation of azoles, instead of azole halides or pseudohalides, with arylboronic acids.
ChemInform Abstract: A Tetranuclear‐Zinc‐Cluster‐Catalyzed Practical and Versatile Deprotection of Acetates and Benzoates.
Authors: Iwasaki Takanori , Agura Kazushi , Maegawa Yusuke , Hayashi Yukiko , Ohshima Takashi , Mashima Kazushi 
Published: January 2011

AbstractA new catalytic deacylation of acetates and benzoates through transesterification with methanol is developed.
ChemInform Abstract: Base‐Catalyzed Isomerization of 2‐Isoxazolines Enables a Two‐Step Enantioselective Synthesis of β‐Hydroxynitriles from Enals.
Authors: Pohjakallio Antti , Pihko Petri M. , Liu Jun 
Published: January 2011

AbstractTreatment of chiral isoxazoles with catalytic amounts of DBU results in efficient formation of optically active β‐hydroxynitriles.
ChemInform Abstract: Selective Arylation of Aldehydes with Di‐Rhodium(II)/NHC Catalysts.
Authors: Trindade Alexandre F. , Andre Vania , Duarte M. Teresa , Veiros Luis F. , Gois Pedro M. P. , Afonso Carlos A. M. 
Published: January 2011

AbstractNovel title ligands are designed and complex (I) is found to show enhanced activity in the arylation of aldehydes with boronic acids.
ChemInform Abstract: Regio‐ and Enantioselective Iridium‐Catalyzed Allylation of Thiophenol: Synthesis of Enantiopure Allyl Phenyl Sulfides.
Authors: Zheng Shengcai , Gao Ning , Liu Wei , Liu Dongge , Zhao Xiaoming , Cohen Theodore 
Published: January 2011

AbstractA highly regio‐ and enantioselective reaction of allylic carbonates with sodium thiophenolate is realized under conditions A.
ChemInform Abstract: Highly Regio‐ and Stereoselective Hydration of 1,2‐Allenylic Sulfoxides.
Authors: Fang Zhao , Zhou Chao , Fu Chunling , Ma Shengming 
Published: January 2011

AbstractA highly regio‐ and stereoselective hydration of 1,2‐allenylic sulfoxides with a proton as the electrophile affords 3‐sulfoxyl‐(Z)‐alkenols via a five‐membered intermediate.
ChemInform Abstract: Progressive Release of a Palladium‐Pyridyl Complex from a Layer‐by‐Layer Multilayer and Illustrative Application to Catalytic Suzuki Coupling.
Authors: Gao Shuiying , Zheng Zhaoliang , Lue Jian , Cao Rong 
Published: January 2011

AbstractQuartz slides bearing polyethyleneimine—PdCl2/Azpy multilayer films are found to liberate catalytic amounts of a soluble active palladium species, which efficiently promotes Suzuki cross‐coupling under mild conditions.
ChemInform Abstract: syn‐Selective Rhodium(I)‐Catalyzed Allylations of Ketimines Proceeding Through a Directed C—H Activation/Allene Addition Sequence.
Authors: Tran Duc N. , Cramer Nicolai 
Published: January 2011

AbstractRhodium‐catalyzed reaction of unsubstituted ketimines with terminal allenes proceeds with excellent syn‐diastereoselectivity to give aminoindan derivatives, e.g. (III) or (VI).
ChemInform Abstract: A Novel Oxidative Cyclization onto Vinyl Silanes.
Authors: Donohoe Timothy J. , Winship Paul C. M. , Pilgrim Ben S. , Walter Daryl S. , Callens Cedric K. A. 
Published: January 2011

AbstractA variety of tetrahydrofurans bearing a silyl group at the ring junction is prepared in good yields stereoselectively via a osmium‐catalyzed oxidative cyclization of appropriate terminal vinyl silanes.
ChemInform Abstract: A Highly Efficient Asymmetric Michael Addition of α,α‐Disubstituted Aldehydes to Maleimides Catalyzed by Primary Amine Thiourea Salt.
Authors: Yu Feng , Jin Zhichao , Huang Huicai , Ye Tingting , Liang Xinmiao , Ye Jinxing 
Published: January 2011

AbstractThe asymmetric Michael addition of challenging α,α‐disubstituted aldehydes to maleimides affords quaternary carbon centers with high enantioselectivities.
ChemInform Abstract: Asymmetric Synthesis of Indolines by Catalytic Enantioselective Reduction of 3H‐Indoles.
Authors: Rueping Magnus , Brinkmann Claus , Antonchick Andrey P. , Atodiresei Iuliana 
Published: January 2011

AbstractTransfer hydrogenation of indole derivatives with Hantzsch dihydropyridine as the hydrogen source and chiral Broensted acid catalysts is an efficient method for the synthesis of optically active title compounds.
ChemInform Abstract: A Ligand‐Free Copper(I) Catalyzed Intramolecular N‐Arylation of Diazoaminobenzenes in PEG‐Water: An Expeditious Protocol Towards Regiospecific 1‐Aryl Benzotriazoles.
Authors: Mukhopadhyay Chhanda , Tapaswi Pradip Kumar , Butcher Ray J. 
Published: January 2011

AbstractThis strategy allows the construction of a wide range of different benzo and pyrido‐triazoles both being important medicinal scaffolds in excellent yields maintaining a green protocol.
ChemInform Abstract: A Highly Adaptable Catalyst/Substrate System for the Synthesis of Substituted Chromenes.
Authors: Aponick Aaron , Biannic Berenger , Jong Michael R. 
Published: January 2011

AbstractThe Au‐catalyzed endo‐cyclization of 2‐(1‐hydroxyallyl)‐phenols (I), (III) and (V) is reported.
ChemInform Abstract: Enantio‐ and Diastereoselective Synthesis of Piperidines by Coupling of Four Components in a “One‐Pot” Sequence Involving Diphenylprolinol Silyl Ether Mediated Michael Reaction.
Authors: Urushima Tatsuya , Sakamoto Daisuke , Ishikawa Hayato , Hayashi Yujiro 
Published: January 2011

AbstractThe sequence involves asymmetric Michael reaction of nitroalkenes with aldehydes followed by an aza‐Henry reaction/hemiaminalization and final nucleophilic substitution or reduction.
ChemInform Abstract: Ester‐ and Ketone‐Substituted (.+‐.)‐1‐Alkyl‐6‐nitro‐1,2,3,4‐tetrahydroquinolines by a Tandem SNAr‐Michael Reaction.
Authors: Bunce Richard A. , Lee Eric J. 
Published: January 2011

AbstractMechanistic aspects of the cyclization reaction to (V) are studied.
ChemInform Abstract: Fatty Acid Synthase Inhibitors of Phenolic Constituents Isolated from Garcinia mangostana.
Authors: Zhao You Xing , et al. et al. 
Published: January 2011

Abstract13 Benzophenones and xanthanes including the new compound (I) are isolated from the hulls of Garcinia mangostana and evaluated for their inhibitory activities against fatty acid synthase (FAS).
ChemInform Abstract: A Novel 18F‐Labeled Pyridyl Benzofuran Derivative for Imaging of β‐Amyloid Plaques in Alzheimer′s Brains.
Authors: Cheng Yan , Ono Masahiro , Kimura Hiroyuki , Kagawa Shinya , Nishii Ryuichi , Saji Hideo 
Published: January 2011

AbstractThe novel pyridyl benzofuran derivative (I) and the corresponding 18F‐labeled compound are prepared and used for imaging of β‐amyloid plaques in Alzheimer′s disease brains.
Toward a Complete Understanding of the Vinyl Fluoride Spectrum in the Atmospheric Region
Authors: Tasinato Nicola , Stoppa Paolo , Charmet Andrea Pietropolli , Giorgianni Santi , Buffa Giovanni , Gambi Alberto 
Published: January 2011

AbstractA deep and comprehensive investigation of the vinyl fluoride (CH2CHF) spectrum in the atmospheric window around 8.7 μm is presented. At first, the ro‐vibrational patterns are modelled to an effective Hamiltonian, which also takes into account the coupling of the CF stretching vibration, ν7, with the neighbouring vibrational combination ν9+ν12. The obtained Hamiltonian gives very accurate simulations and predictions of the ro‐vibrational quantum energies. Then, in the main part of the work, an experimental and theoretical study of vinyl fluoride self‐broadening collisions is carried out for the first time. The broadening coefficients obtained experimentally are compared with those calculated by a semiclassical theory, demonstrating a significant contribution of collisional coupling effects between lines connecting pairs of degenerate (or nearly degenerate) rotational levels. Finally, the experimentally retrieved integrated absorption coefficients are used to calculate the absorption cross‐section of the ν7 normal mode, from which dipole transition moments are derived. The obtained results provide a deep insight into the spectral behaviour of vinyl fluoride, in a spectral region of primary relevance for atmospheric and environmental determinations. Indeed, the data presented constitute an accurate model for the remote sensing of vinyl fluoride—a molecule of proved industrial importance which can lead to hazardous effects in the atmosphere and affects human′s health.
The use of in vitro technologies and high‐resolution/accurate‐mass LC‐MS to screen for metabolites of ‘designer’ steroids in the equine
Authors: Clarke Adam , Scarth James , Teale Phil , Pearce Clive , Hillyer Lynn 
Published: January 2011

AbstractDetection of androgenic‐anabolic steroid abuse in equine sports requires knowledge of the drug's metabolism in order to target appropriate metabolites, especially where urine is the matrix of choice. Studying ‘designer’ steroid metabolism is problematic since it is difficult to obtain ethical approval for in vivo metabolism studies due to a lack of toxicological data.In this study, the equine in vitro metabolism of eight steroids available for purchase on the Internet is reported; including androsta‐1,4,6‐triene‐3,17‐dione, 4‐chloro,17α‐methyl‐androsta‐1,4‐diene‐3,17β‐diol, estra‐4,9‐diene‐3,17‐dione, 4‐hydroxyandrostenedione, 20‐hydroxyecdysone, 11‐keto‐androstenedione, 17α‐methyldrostanolone, and tetrahydrogestrinone. In order to allow for retrospective analysis of sample testing data, the use of a high‐resolution (HR) accurate‐mass Thermo LTQ‐Orbitrap liquid chromatography‐mass spectrometry (LC‐MS) instrument was employed for metabolite identification of underivatized sample extracts. The full scan LC‐HRMS Orbitrap data were complimented by LC‐HRMS/MS and gas‐chromatography‐mass spectrometry (GC‐MS) experiments in order to provide fragmentation information and to ascertain whether GC‐MS was capable of detecting any metabolite not detected by LC‐HRMS.With the exception of 20‐hydroxyecdysone, all compounds were found to be metabolized by equine liver S9 and/or microsomes. With the exception of 17α‐methyldrostanolone, which produced metabolites that could only be detected by GC‐MS, the metabolites of all other compounds could be identified using LC‐HRMS, thus allowing retrospective analysis of previously acquired full‐scan data resulting from routine equine drug testing screens. In summary, while in vitro techniques do not serve as a replacement for more definitive in vivo studies in all situations, their use does offer an alternative in situations where it would not be ethical to administer untested drugs to animals. Copyright © 2011 John Wiley & Sons, Ltd.
Strontium Methylphosphonate Trihydrate: An Example of a New Class of Host Materials for Intercalation Reactions – Synthesis, Structure and Intercalation Behavior
Authors: Beneš Ludvík , Melánová Klára , Svoboda Jan , Zima Vítězslav , Růžička Aleš , Trchová Miroslava 
Published: January 2011

AbstractA new compound with formula SrCH3PO3·3H2O has been prepared, characterized by thermogravimetry, IR spectroscopy and powder X‐ray diffraction, and its structure has been determined from single‐crystal X‐ray diffraction data. Strontium methylphosphonate trihydrate crystallizes in an orthorhombic system with space group Pbca (No. 61), Z = 8 and with lattice parameters a = 7.8838(6), b = 8.5173(5), c = 21.5272(15) Å. Primary alcohols, amines, and 1,2‐diols with straight carbon chains were intercalated into this strontium methylphosphonate compound. For all three types of intercalate, a linear dependence of the interlayer distance on the number of carbon atoms in the aliphatic chain of the guest was found. From these results, the arrangements of the guest molecules in the interlayer space of the host (SrCH3PO3) structure were deduced. The amine intercalates are unstable, and the guest species can be released from the host by washing the intercalate with an aprotic solvent. Conversely, the alcohol and diol intercalates are surprisingly stable. The reason for this stability may be due to the fact that the oxygen atom of an alcohol or diol species can replace the oxygen atom of the coordinated water molecule in the host. A successful attempt to intercalate polymeric species, namely poly(ethylene glycol), was made, which opens the way for the preparation of nanocomposites with this type of hostmaterial.
Cyanide and Carbon Monoxide Ligand Formation in Hydrogenase Biosynthesis
Authors: Swanson Kevin D. , Duffus Benjamin R. , Beard Trevor E. , Peters John W. , Broderick Joan B. 
Published: January 2011

AbstractCarbon monoxide (CO) and cyanide (CN–) can act as potent inhibitors of enzymes necessary for primary biochemical processes, however they also play important roles in biological systems. Well‐studied cases include CN– biosynthesis in plants to act as a defense against herbivores and pathogens, CN– biosynthesis in certain species of bacteria to remove excess glycine, and CO biosynthesis by microbes for energy metabolism in the Wood–Ljungdahl pathway. The utilization of CO and CN– as essential metal ligands in biology is even more limited, with the only known examples being at the active sites of hydrogenase enzymes. This class of enzymes catalyzes the reversible oxidation of hydrogen, a reaction that in biology appears to be entirely dependent on the presence of CO and/or CN– ligands. To date, synthetic mimicsof hydrogenase active sites have not reproduced hydrogen production rates observed in some hydrogenases; it is thus of considerable interest to understand how biology has solved the intriguing problem of biosynthesizing efficient hydrogen catalysts. Of the hydrogenase enzymes discussed herein, recent advances in the [FeFe]‐hydrogenase family has provided important insights into the synthesis of the CO and CN– ligands for its active site (H‐cluster). Biosynthesis of the complex [FeFe]‐hydrogenase active site requires only three iron–sulfur cluster‐containing maturation proteins, where two act as radical S‐adenosylmethionine (AdoMet) enzymes (HydE and HydG) and the other as a GTPase (HydF). In this review, biological CO and CN– genesis mechanisms will be assessed with specific focus on [FeFe]‐hydrogenase maturation.
Photoactive Europium Hybrids of β‐Diketone‐Modified Polysilsesquioxane Bridge Linking Si–O–B(Ti)–O Xerogels
Authors: Wang Chang , Yan Bing , Liu Jin‐Liang , Guo Lei 
Published: January 2011

AbstractPolysilsesquioxane bridges are obtained through the single modification of 3‐(triethoxysilyl)propyl isocyanate (TEPIC) by two β‐diketone ligands [thenoyltrifluoroacetylacetone (TTA) and trifluoroacetylacetone (TA)], which behave as linkages between the europium ion and composite host Si–O–M (M = B or Ti) xerogels by controlling the hydrolysis rate of the alkoxy compounds (tetraethyl orthosilicate, titanium butoxide and tributyl borate). Subsequently, luminescent europium hybrid xerogels are assembled and characterized by NMR, Fourier transform infrared (FTIR), ultraviolet absorption and ultraviolet/visible diffuse reflection spectroscopy, X‐ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and photoluminescence spectroscopy through which the decay times (τ) and quantum efficiency (η) can be determined. These results reveal that the lanthanide complexes have been covalently immobilized into the composite inorganic xerogels and the obtained hybrids have the excellent ability of light absorption and emission. The hybrids with composite Si–O–B xerogels possess the matched photoluminescent properties (red emission intensity, lifetimes, and quantum efficiency) as the pure silica oxygen network, both of which show a superior luminescence performance than the hybrids with composite Si–O–Ti xerogels. Besides, the single modification of TTA is favorable for the luminescence of the hybrid xerogels.
DNA Photocleavage and Cytotoxic Properties of Ferrocene Conjugates
Authors: Maity Basudev , Chakravarthi Balabhadrapatruni V. S. K. , Roy Mithun , Karande Anjali A. , Chakravarty Akhil R. 
Published: January 2011

AbstractFerrocenyl conjugates 2‐ferrocenylimidazophenanthroline (1) and 2‐ferrocenylimidazophenanthrene (2) were prepared, characterized, and their photoinduced DNA cleavage and photocytotoxic activity were studied. 2‐Phenylimidazophenanthroline (3) was used as a control species. Compound 2 was characterized by X‐ray crystallography. The interaction of the compounds with double‐stranded calf thymus DNA (CT DNA) was studied. The compounds show good binding affinity to CT DNA with Kb values of approximately 105 M–1. Thermal denaturation data suggest the groove binding nature of the compounds. The redox‐active compounds show poor chemical nuclease activity in the presence of hydrogen peroxide and glutathione (GSH). Compound 1 exhibits significant DNA photocleavage activity in visible light of 476 and 532 nm. Compound 3 shows only moderate DNA cleavage activity. The positive effect of the ferrocenyl moiety is demonstrated by the DNA photocleavage data. Mechanistic investigations reveal the formation of superoxide as well as hydroxyl radicals as the active species. The photocytotoxicity of the compounds in HeLa cells was studied upon irradiation with visible light (400–700 nm). Compound 1 shows efficient photocytotoxic activity with an IC50 value of 13 μM, while compounds 2 and 3 are less active with IC50 values of >50 and 22 μM, respectively.
Can we reduce the number of fish in the OECD acute toxicity test?
Authors: Rufli Hans , Springer Timothy A 
Published: January 2011

AbstractOECD (Organisation for Economic Co-operation and Development) Guideline 203, Fish Acute Toxicity Test, states that the test should be performed using at least five concentrations in a geometric series with a separation factor not exceeding 2.2, with at least seven fish per concentration. However, the efficiency of this design can be questioned, because it often results in only one concentration that causes partial mortality (mortality &gt;0% and &lt;100%). We performed Monte Carlo computer simulations to assess whether more efficient designs could allow reductions in fish use. Simulations indicated that testing with six fish per concentration could yield 50% lethal concentration (LC50) estimates of quality similar to those obtained using seven fish. Experts attending a workshop organized to consider this finding and to identify the best methods for reducing fish use concluded that significant reductions could best be achieved by modifying the test paradigm. They suggested initiating testing using a 96-h fish embryo test instead of juvenile fish to cover the range from the upper threshold concentration (the lowest 50% effective concentration [EC50] in existing algae and daphnia studies) to the highest concentration with no mortality. This would be followed by a confirmatory limit test with juvenile fish at the highest concentration with no mortality or by a full test with juvenile fish, if a point estimate of the LC50 is required. Environ. Toxicol. Chem. 2011; 30:1006–1011. © 2010 SETAC