bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a Functional cis‐Prolyl Bond Biomimetic and Mechanistic Implications for Nickel Superoxide Dismutase
Authors: Tietze Daniel , Tischler Marco , Voigt Stephan , Imhof Diana , Ohlenschläger Oliver , Görlach Matthias , Buntkowsky Gerd 
Published: May 2010

AbstractDuring recent years several peptide‐based Ni superoxide dismutase (NiSOD) models have been developed. These NiSOD models show an important structural difference compared to the native NiSOD enzyme, which could cause a completely different mechanism of superoxide dismutation. In the native enzyme the peptide bond between Leu4 and Pro5 is cis‐configured, while the NiSOD models exhibit a trans‐configured peptide bond between these two residues. To shed light on how the configuration of this single peptide bond influences the activity of the NiSOD model peptides, a new cis‐prolyl bond surrogate was developed. As surrogate we chose a leucine/alanine‐based disubstituted 1,2,3‐triazole, which was incorporated into the NiSOD model peptide replacing residues Leu4 and Pro5. The yielded 1,5‐disubstituted triazole nickel peptide exhibited high SOD activity, which was approximately the same activity as its parent trans‐configured analogue. Hence, the conformation of the prolyl peptide bond apparently has of minor importance for the catalytic activity of the metallopeptides as postulated in literature. Furthermore, it is shown that the triazole metallopeptide is forming a stable cyanide adduct as a substrate analogue model complex.
Two‐Photon Chemistry in Ruthenium 2,2′‐Bipyridyl‐Functionalized Single‐Wall Carbon Nanotubes
Authors: Martín Roberto , Jiménez Liliana , Alvaro Mercedes , Scaiano Juan C. , Garcia Hermenegildo 
Published: May 2010

AbstractRuthenium polypyridyl complexes are widely used as light harvesters in dye‐sensitized solar cells. Since one of the potential applications of single‐wall carbon nanotubes (SWCNTs) and their derived materials is their use as active components in organic and hybrid solar cells, the study of the photochemistry of SWCNTs with tethered ruthenium polypyridyl complexes is important. A water‐soluble ruthenium tris(bipyridyl) complex linked through peptidic bonds to SWCNTs (Ru‐SWCNTs) was prepared by radical addition of thiol‐terminated SWCNT to a terminal CC double bond of a bipyridyl ligand of the ruthenium tris(bipyridyl) complex. The resulting macromolecular Ru‐SWCNT (≈500 nm, 15.6 % ruthenium complex content) was water‐soluble and was characterized by using TEM, thermogravimetric analysis, chemical analysis, and optical spectroscopy. The emission of Ru‐SWCNT is 1.6 times weaker than that of a mixture of [Ru(bpy)3]2+ and SWCNT of similar concentration. Time‐resolved absorption optical spectroscopy allows the detection of the [Ru(bpy)3]2+‐excited triplet and [Ru(bpy)3]+. The laser flash studies reveal that Ru‐SWCNT exhibits an unprecedented two‐photon process that is enabled by the semiconducting properties of the SWCNT. Thus, the effect of the excitation wavelength and laser power on the transient spectra indicate that upon excitation of two [Ru(bpy)3]2+ complexes of Ru‐SWCNT, a disproportionation process occurs leading to delayed formation of [Ru(bpy)3]+ and the performance of the SWCNT as a semiconductor. This two‐photon delayed [Ru(bpy)3]+ generation is not observed in the photolysis of [Ru(bpy)3]3+; SWCNT acts as an electron wire or electron relay in the disproportionation of two [Ru(bpy)3]2+ triplets in a process that illustrates that the SWCNT plays a key role in the process. We propose a mechanism for this two‐photon disproportionation compatible with i) the need for high laser flux, ii) the long lifetime of the [Ru(bpy)3]2+ triplets, iii) the semiconducting properties of the SWNT, and iv) the energy of the HOMO/LUMO levels involved.
Synthetic and Structural Studies of 1,8‐Chalcogen Naphthalene Derivatives
Authors: Knight Fergus R. , Fuller Amy L. , Bühl Michael , Slawin Alexandra M. Z. , Woollins J. Derek 
Published: May 2010

AbstractFour novel 1,8‐disubstituted naphthalene derivatives 4–7 that contain chalcogen atoms occupying the peri positions have been prepared and fully characterised by using X‐ray crystallography, multinuclear NMR spectroscopy, IR spectroscopy and MS. Molecular distortion due to noncovalent substituent interactions was studied as a function of the bulk of the interacting chalcogen atoms and the size and nature of the alkyl group attached to them. X‐ray data for 4–7 was compared to the series of known 1,8‐bis(phenylchalcogeno)naphthalenes 1–3, which were themselves prepared from novel synthetic routes. A general increase in the E⋅⋅⋅E′ distance was observed for molecules containing bulkier atoms at the peri positions. The decreased S⋅⋅⋅S distance from phenyl‐1 and ethyl‐4 analogues is ascribed to a weaker chalcogen lone pair–lone pair repulsion acting in the ethyl analogue due to the presence of two equatorial S(naphthyl) ring conformations. Two novel peri‐substituted naphthalene sulfoxides of 1, Nap(OSPh)(SPh) 8 and Nap(OSPh)2 9, which contain different valence states of sulfur, were prepared and fully characterised by using X‐ray crystallography and multinuclear NMR spectroscopy, IR spectroscopy and MS. Molecular structures were analysed by using naphthalene ring torsions, peri‐atom displacement, splay angle magnitude, S⋅⋅⋅S interactions, aromatic ring orientations and quasi‐linear OS⋅⋅⋅S arrangements. The axial S(naphthyl) rings in 8 and 9 are unfavourable for S⋅⋅⋅S contacts due to stronger chalcogen lone pair–lone pair repulsion. Although quasi‐linear OS⋅⋅⋅S alignments suggest attractive interaction is conceivable, analysis of the B3LYP wavefunctions affords no evidence for direct bonding interactions between the S atoms.
Syntheses and Characterization of (C2F5)3BCO and (C3F7)3BCO
Authors: Gerken Michael , Pawelke Gottfried , Bernhardt Eduard , Willner Helge 
Published: May 2010

AbstractThe new tris(perfluoroalkyl)borane carbonyls, (C2F5)3BCO and (C3F7)3BCO, were prepared by means of a novel synthetic route using commercially available precursors by reacting K[(C2F5)3BCOOH] and K[(C3F7)3BCOOH] with concentrated sulfuric acid in the last step. The carboxylic acids, K[(C2F5)3BCOOH] and K[(C3F7)3BCOOH], were prepared by oxidative cleavage of the CC triple bonds in Cs[(C2F5)3BCCPh] and Cs[(C3F7)3BCCPh] in a two‐step process to yield K[(C2F5)3BCOCOPh] and K[(C3F7)3BCOCOPh] as isolable intermediates. Crystal structures were obtained of K[(C2F5)3BCOCOPh], K[(C2F5)3BCOOH]⋅H2O, (C2F5)3BCO, K[(C3F7)3BCOOH] ⋅2 H2O, and (C3F7)3BCO. In the crystal structures of (C2F5)3BCO and (C3F7)3BCO the CO bond lengths are 1.109(2) and 1.103(5) Å, respectively, which are among the shortest observed to date. Tris(pentafluoroethyl)borane carbonyl and (C3F7)3BCO slowly decompose at room temperature to yield CO, difluoroperfluoroalkylboranes and perfluoroalkenes. The decomposition of (C2F5)3BCO was found to follow a first‐order rate law with Ea=107 kJ mol−1.
On the Dewar–Chatt–Duncanson Model for Catalytic Gold(I) Complexes
Authors: Salvi Nicola , Belpassi Leonardo , Tarantelli Francesco 
Published: May 2010

AbstractWe provide a rigorous model‐free definition and a detailed theoretical analysis of the electron‐charge displacements making up the donation and back‐donation components of the Dewar–Chatt–Duncanson model in some realistic catalytic intermediates of formula L–AuI–S in which L is an N‐heterocyclic carbene or Cl− and S is an η2‐coordinated substrate containing a CC multiple bond. We thus show, contrary to a widely held view, that the goldsubstrate bond is characterized by a large π back‐donation component that is comparable to, and often as large as, the σ donation. The back‐donation is found to be a highly tunable bond component and we analyze its relationship with the nature of the auxiliary ligand L and with structural (interdependent) factors such as metal–substrate bond lengths and carbon pyramidalization.
ChemInform Abstract: A Vanadium Tellurate, (NH4)2[VO2]2 [TeO4(OH)2], Containing Two Edge‐Shared Square‐Pyramidal VO5 Groups.
Authors: Yun Gyiae , Hwang Yunmi , Yun Hoseop , Do Junghwan , Jacobson Allan J. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Fluoride Ion Donor Properties of cis‐OsO2F4: Synthesis, Raman Spectroscopic Study, and X‐Ray Crystal Structure of [OsO2F3][Sb2F11].
Authors: Hughes Michael J. , Mercier Helene P. A. , Schrobilgen Gary J. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Dynamic Kinetic Asymmetric Transformation (DYKAT) by Combined Amine‐ and Transition‐Metal‐Catalyzed Enantioselective Cycloisomerization.
Authors: Zhao Gui‐Ling , Ullah Farman , Deiana Luca , Lin Shuangzheng , Zhang Qiong , Sun Junliang , Ibrahem Ismail , Dziedzic Pawel , Cordova Armando 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Type of Organocatalyst for Highly Stereoselective Michael Addition of Ketones to Nitroolefins on Water.
Authors: Syu Siang‐en , Kao Tzu‐Ting , Lin Wenwei 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Copper‐Catalyzed Bromoalkynylation of Arynes.
Authors: Morishita Takami , Yoshida Hiroto , Ohshita Joji 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Regioselective Synthesis of 2,4‐(Dioxobutyl)dihydroquinolines and ‐pyridines by Chloroformiate‐Mediated Reaction of 1,3‐Bis(silyl enol ethers) with Quinolines and Pyridines.
Authors: Albrecht Uwe , Preuss Anja , Schmidt Andreas , Fischer Christine , Langer Peter 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Novel Convenient Synthesis of 5‐Acyl‐1,2‐dihydropyrimidin‐2‐ones via 4‐Trichloromethyl‐1,2,3,4‐tetrahydropyrimidin‐2‐ones.
Authors: Fesenko Anastasia A. , Solovyev Pavel A. , Shutalev Anatoly D. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Production of a New Type of Amidepsine with a Sugar Moiety by Static Fermentation of Humicola sp. FO‐2942.
Authors: Inokoshi Junji , Takagi Yoichi , Uchida Ryuji , Masuma Rokuro , Omura Satoshi , Tomoda Hiroshi 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Antipain Y, a New Antipain Analogue that Inhibits Neurotransmitter Release from Rat Dorsal Root Ganglion Neurons.
Authors: Nakae Koichi , Kojima Fukiko , Sawa Ryuichi , Kubota Yumiko , Igarashi Masayuki , Kinoshita Naoko , Adachi Hayamitsu , Nishimura Yoshio , Akamatsu Yuzuru 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sonogashira Reactions of α‐ and β‐1‐Ethynyl‐2‐deoxyribosides: Synthesis of Acetylene‐Extended C‐Nucleosides.
Authors: Bobula Tomas , Hocek Michal , Kotora Martin 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Magnetic and Structural Properties of the Most Important Alloys of Iron Produced by Mechanical Alloying
Authors: Shokrollahi H. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Role of the Indole in Important Organocatalytic Enantioselective Friedel—Crafts Alkylation Reactions
Authors: Marques‐Lopez Eugenia , Diez‐Martinez Alba , Merino Pedro , Herrera Raquel P. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Recent Advances in the Mitsunobu Reaction. Modifications and Applications to Biologically Active Molecules
Authors: Reynolds A. J. , Kassiou M. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: anti‐Aging Studies on the Senescence Accelerated Mouse (SAM) Strains
Authors: Takahashi Ryoya 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Structural Concepts of Novel Supramolecular Proton Transfer Compounds and Their Metal Complexes
Authors: Aghabozorg H. , Manteghi F. , Sheshmani S. 
Published: May 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Experimental and theoretical study of gas hydrate formation in a high‐pressure flow loop
Authors: Sarshar Mohammad , Fathikalajahi Jamshid , Esmaeilzadeh Ferreidun 
Published: May 2010

AbstractA set of mathematical models are developed based on thermodynamics, mass transfer, and crystallisation concepts to predict hydrate formation rate and the aqueous phase composition in the flow loop. In order to validate the model, experimental study is carried out in a 10 m loop with the inside diameter of 10.6 mm using gas mixture of 73% methane and 27% propane to measure the hydrate formation rate. The experimental conditions include temperature from 4 to 5°C and pressures between 2 and 3 MPa. Good agreements are noticed when the experimental and theoretical hydrate formation rates are compared at different operating conditions.
FEAST—realization of hardware‐oriented numerics for HPC simulations with finite elements
Authors: Turek Stefan , Göddeke Dominik , Becker Christian , Buijssen Sven H. M. , Wobker Hilmar 
Published: May 2010

AbstractFEAST (Finite Element Analysis and Solutions Tools) is a Finite Element‐based solver toolkit for the simulation of PDE problems on parallel HPC systems, which implements the concept of ‘hardware‐oriented numerics’, a holistic approach aiming at optimal performance for modern numerics. In this paper, we describe this concept and the modular design that enables applications built on top of FEAST to execute efficiently, without any code modifications, on commodity‐based clusters, the NEC SX 8 and GPU‐accelerated clusters. We demonstrate good performance and weak and strong scalability for the prototypical Poisson problem and more challenging applications from solid mechanics and fluid dynamics. Copyright © 2010 John Wiley & Sons, Ltd.
A comparison between taste avoidance and conditioned disgust reactions induced by ethanol and lithium chloride in preweanling rats
Authors: Arias Carlos , Pautassi Ricardo Marcos , Molina Juan Carlos , Spear Norman E. 
Published: May 2010

AbstractAdult rats display taste avoidance and disgust reactions when stimulated with gustatory stimuli previously paired with aversive agents such as lithium chloride (LiCl). By the second postnatal week of life, preweanling rats also display specific behaviors in response to a tastant conditioned stimulus (CS) that predicts LiCl‐induced malaise. The present study compared conditioned disgust reactions induced by LiCl or ethanol (EtOH) in preweanling rats. InExperiment 1we determined doses of ethanol and LiCl that exert similar levels of conditioned taste avoidance. After having equated drug dosage in terms of conditioned taste avoidance, 13‐day‐old rats were given a single pairing of a novel taste (saccharin) and either LiCl or ethanol (2.5 g/kg; Experiment 2). Saccharin intake and emission of disgust reactions were assessed 24 and 48 hr after training. Pups given paired presentations of saccharin and the aversive agents (ethanol or LiCl) consumed less saccharin during the first testing day than controls. These pups also showed more aversive behavioral reactions to the gustatory CS than controls. Specifically, increased amounts of grooming, general activity, head shaking, and wall climbing as well as reduced mouthing were observed in response to the CS. Conditioned aversive reactions but not taste avoidance were still evident on the second testing day. In conclusion, a taste CS paired with postabsorptive effects of EtOH and LiCl elicited a similar pattern of conditioned rejection reactions in preweanling rats. These results suggest that similar mechanisms may be underlying CTAs induced by LiCl and a relatively high EtOH dose. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 545–557, 2010.
The ontogeny of anxiety‐like behavior in rats from adolescence to adulthood
Authors: Lynn Debra A. , Brown Gillian R. 
Published: May 2010

AbstractIn human beings, susceptibility to anxiety disorders can be relatively high during adolescence. Understanding the ontogeny of anxiety‐like behavior in laboratory rodents has implications for developing anxiolytic drugs that are suitable for this age group. Given the dearth of information about adolescent rodents, this study examined the response of both male and female adolescent, late adolescent, young adult, and older adult rats to three tests of anxiety‐like behavior: the emergence test (ET), open field (OF), and elevated plus‐maze (EPM). The results showed that adolescent rats exhibited a higher anxiety‐like response than adults on each test; the amount of locomotion in the OF and percentage of time spent on the open arms of the EPM increased across the age groups, while older adult rats made the fewest start box re‐entries in the ET. These results support the hypothesis that adolescent rats have a more pronounced response to stressors than do adults. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 731–739, 2010.
Ruthenium(II) Complexes of Carboxylated Terpyridines and Dipyrazinylpyridines
Authors: Stublla Arta , Potvin Pierre G. 
Published: May 2010

AbstractOne‐pot preparations of carboxylated 2,2′;6′,2″‐terpyridine and 2,6‐dipyrazin‐2‐ylpyridine ligands are reported in free acid and ester forms, as well as their transformations to homoleptic RuII complexes in very good yields. Density functional theory calculations of their geometry‐optimized structures enabled their comparison with crystal structures; although the gross features of the crystal structures were reproduced, they showed much variability and distortion. The spectroscopic and electrochemical properties were analyzed from the point of view of their geometry‐optimized structures, molecular orbital characteristics and electronic transitions, specifically to assess the effects of carboxylation and of inserting a phenylene spacer between the tridentate portion and the carboxyl group. The dipyrazinylpyridine complexes had HOMO levels stabilized by approximately 1 eV relative to the terpyridine analogues, and showed positive‐shifted electrochemical potentials and redshifted electronic absorptions. Phenylene spacers were found to act as electron‐donating groups, and the lowest‐energy UV/Vis transitions showed intraligand character.
Competing Regiodirecting Effects of Ester and Aryl Groups in [3+3] Cyclocondensations of 1,3‐Bis(trimethylsilyloxy)‐1,3‐butadienes: Regioselective Synthesis of 3‐Hydroxyphthalates and 2‐Hydroxyterephthalates
Authors: Shkoor Mohanad , Fatunsin Olumide , Riahi Abdolmajid , Lubbe Mathias , Reim Stefanie , Sher Muhammad , Villinger Alexander , Fischer Christine , Langer Peter 
Published: May 2010

Abstract3‐Hydroxy‐5‐methylphthalates are prepared by regioselective chelation‐controlled cyclization of 1,3‐bis(silyloxy)‐1,3‐butadienes with 4‐silyloxy‐2‐oxo‐3‐butenoates derived from acetylpyruvates. The employment of silylated benzoylpyruvates instead of acetylpyruvates results in a regioselectivity change and the formation of 6‐aryl‐2‐hydroxyterephthalates. The cyclization of 1,3‐bis(silyloxy)‐1,3‐butadienes with 4‐ethoxy‐2‐oxo‐3‐butenoates, readily available by condensation of enol ethers with methyl 2‐chloro‐2‐oxoacetate, provides a convenient approach to 2‐hydroxyterephthalates and 3‐hydroxyphthalates depending on the substitution pattern of the diene.