bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chiral Hypervalent Iodine Reagents: Synthesis and Reactivity
Authors: Parra Alejandro , Reboredo Silvia 
Published: November 2013

AbstractChiral hypervalent iodine chemistry has been steadily increasing in importance in recent years. This review catalogues enantioselective transformations triggered by chiral hypervalent iodine(III/V) reagents, in stoichiometric or catalytic quantities, highlighting the different reactivities in terms of yield and enantioselectivity. Moreover, the synthesis of the most remarkable and successful catalysts has been illustrated in detail.
Microwave‐Assisted, Rhodium(III)‐Catalyzed N‐Annulation Reactions of Aryl and α,β‐Unsaturated Ketones with Alkynes
Authors: Lee Hyejeong , Sim Yong‐Kyun , Park Jung‐Woo , Jun Chul‐Ho 
Published: November 2013

AbstractNew RhIII‐catalyzed, one‐pot N‐annulation reactions of aryl and α,β‐unsaturated ketones with alkynes in the presence of ammonium acetate have been developed. Under microwave irradiation conditions, the processes lead to rapid formation of the respective isoquinoline and pyridine derivatives with efficiencies that are strongly dependent on the steric nature of the aryl ring and enone substituents. By employing this protocol, a variety of isoquinoline and pyridine derivatives were prepared in high yields. In addition, a new one‐pot approach to the synthesis of pyridines, involving four‐component reactions of ketones, formaldehyde, NH4OAc, and alkynes, has been uncovered. This process takes place through a route involving initial aldol condensation of the ketone with formaldehyde to generate a branched α,β‐unsaturated ketone that then undergoes RhIII‐catalyzed N‐annulation with NH4OAc and the alkyne.
Toward the peri‐Pentacene Framework
Authors: Zöphel Lukas , Berger Reinhard , Gao Peng , Enkelmann Volker , Baumgarten Martin , Wagner Manfred , Müllen Klaus 
Published: November 2013

AbstractBased on modern pyrene chemistry, a new route toward the synthesis of the peri‐pentacene framework was developed. Firstly, the tetraketo form as stable precursor was targeted, because the fully aromatic peri‐pentacene is predicted to suffer from high instability and reactivity. Therefore, a recently developed 4,5,9,10‐tetrafunctionalization of pyrene was utilized to build up a planar and a dragonfly‐shaped derivative in five steps, which only differ in the two outer bonds between the peripheral benzene rings. The planar tetraketone could only be dissolved in strong acids upon protonation, which limited the use of analytical methods. In contrast, the dragonfly‐shaped form showed excellent organosolubility. In‐depth investigation by NMR spectroscopy revealed co‐existence of atropo‐isomers in solution. The optical and electronic properties were analyzed by UV/Vis spectroscopy and cyclic voltammetry. To approach aromatic conjugation, stepwise reduction in solution by using tetrabutylammonium borohydride was carried out. Reduced species were studied by ESR and UV/Vis spectroscopy, as well as by MALDI‐TOF MS, confirming the formation of the radical anion.
Triisopropylsilylethynyl‐Functionalized Graphene‐Like Fragment Semiconductors: Synthesis, Crystal Packing, and Density Functional Theory Calculations
Authors: Zhang Lei , Fonari Alexandr , Zhang Yue , Zhao Guangyao , Coropceanu Veaceslav , Hu Wenping , Parkin Sean , Brédas Jean‐Luc , Briseno Alejandro L. 
Published: November 2013

AbstractTri‐isopropylsilylethynyl (TIPS)‐functionalized polycyclic aromatic hydrocarbon (PAH) molecules incorporate structural components of graphene nanoribbons and represent a family of model molecules that form organic crystal semiconductors for electronic devices. Here, we report a series of TIPS‐functionalized PAHs and discuss their electronic properties and crystal packing features. We observe that these soluble compounds easily form one‐dimensional (1 D) packing arrangements and allow a direct evolution of the π stacking by varying the geometric shape. We find that the aspect ratio between length and width plays an important role on crystal packing. Our result indicates that when the PAH molecules have zigzag edges, these can provide enough volume for the molecules to rotate and reorient, alleviating the unfavorable electrostatic interactions found in perfectly cofacial π–π stacking. Density functional theory calculations were carried out to provide insights into how the molecular geometric shape influences the electronic structure and transport properties. The calculations indicate that, among the compounds studied here, “brick‐layer” stacks provide the highest hole mobility.
Primary Amines by Transfer Hydrogenative Reductive Amination of Ketones by Using Cyclometalated IrIII Catalysts
Authors: Talwar Dinesh , Salguero Noemí Poyatos , Robertson Craig M. , Xiao Jianliang 
Published: November 2013

AbstractCyclometalated iridium complexes are found to be versatile catalysts for the direct reductive amination (DRA) of carbonyls to give primary amines under transfer‐hydrogenation conditions with ammonium formate as both the nitrogen and hydrogen source. These complexes are easy to synthesise and their ligands can be easily tuned. The activity and chemoselectivity of the catalyst towards primary amines is excellent, with a substrate to catalyst ratio (S/C) of 1000 being feasible. Both aromatic and aliphatic primary amines were obtained in high yields. Moreover, a first example of homogeneously catalysed transfer‐hydrogenative DRA has been realised for β‐keto ethers, leading to the corresponding β‐amino ethers. In addition, non‐natural α‐amino acids could also be obtained in excellent yields with this method.
Tetraphenylethylene Conjugated with a Specific Peptide as a Fluorescence Turn‐On Bioprobe for the Highly Specific Detection and Tracing of Tumor Markers in Live Cancer Cells
Authors: Huang Yanyan , Hu Fang , Zhao Rui , Zhang Guanxin , Yang Hua , Zhang Deqing 
Published: November 2013

AbstractSmart molecular probes and flexible methods are attracting remarkable interest for the visualization of cancer‐related biological and chemical events. In this work, a new fluorescence turn‐on probe with dual‐recognition characteristics for the specific imaging of cancer cells is reported. This new bioprobe is rationally designed by linking tetraphenylethylene (TPE), an aggregation‐induced emission (AIE) fluorophore, with the small peptide IHGHHIISVG (referred to as AP2H), a targeting ligand to the broad‐spectrum cancer‐related protein LAPTM4B. The binding of the probe TPE‐AP2H with the target, both in solution and at the cellular level, switches on the fluorescence of TPE because of the inhibition of internal rotations within the TPE framework. Accordingly, this bioprobe allows the real‐time monitoring and subcellular localization of LAPTM4B in cancer cells, with a very high target‐to‐background ratio for the imaging. Furthermore, brighter fluorescence images are detected after incubation of TPE‐AP2H with tumor cells at lower pH values. Thus, this new bioprobe is more advantageous because it can simultaneously target the LAPTM4B protein and sense the characteristic low‐pH environment of tumor cells. In addition, TPE‐AP2H displays high photostability and low cytotoxicity. Therefore, this new bioprobe is promising for the more accurate and reliable imaging of tumor markers in live cancer cells.
Addition of N‐Acetyl Cysteine to Carvedilol Decreases the Incidence of Acute Renal Injury After Cardiac Surgery
Authors: Ozaydin Mehmet , Peker Tulay , Akcay Selahaddin , Uysal Bayram A. , Yucel Habil , Icli Atilla , Erdogan Dogan , Varol Ercan , Dogan Abdullah , Okutan Huseyin 
Published: November 2013

ABSTRACTBackgroundOxidative stress and inflammation during cardiac surgery may be associated with acute renal injury (ARI). N‐acetyl cysteine (NAC) and carvedilol have antioxidant and anti‐inflammatory properties.HypothesisA combination of carvedilol and NAC should decrease the incidence of ARI more than metoprolol or carvedilol.MethodsPatients undergoing cardiac surgery were randomized to metoprolol, carvedilol, or carvedilol plus NAC. End points were occurrence of ARI and change in preoperative to postoperative peak creatinine levels.ResultsARI incidence was lower in the carvedilol plus NAC group compared with the metoprolol (21.0% vs 42.1%; P = 0.002) or carvedilol (21.0% vs 38.6%; P = 0.006) groups, but was similar between the metoprolol and carvedilol groups (P = 0.62). Preoperative and postoperative day 1 creatinine levels were similar among the metoprolol (1.02 [0.9–1.2] and 1.2 [0.92–1.45]) the carvedilol (1.0 [0.88–1.08] and 1.2 [0.9–1.5]) and the carvedilol plus NAC groups (1.06 [0.9–1.18] and 1.1 [1.0–1.21] mg/dL; all P values >0.05). Postoperative day 3, day 5, and peak creatinine levels were lower in the carvedilol plus NAC group (1.11 [1.0–1.23], 1.14 [1.0–1.25] and 1.15 [1.0–1.25]) as compared with the metoprolol (1.4 [1.3–1.49], 1.3 [1.0–1.54] and 1.3 [1.0–1.54]) or carvedilol groups (1.2 [1.0–1.52], 1.25 [1.0–1.52] and 1.25 [1.0–1.55] mg/dL; all P values <0.05), but were similar between the metoprolol and carvedilol groups (all P values >0.05).ConclusionsCombined carvedilol and NAC decreased ARI incidence as compared with carvedilol or metoprolol. No difference was detected between carvedilol and metoprolol.
Lead Evaluation of Tetrahydroquinolines as Nonsteroidal Selective Androgen Receptor Modulators for the Treatment of Osteoporosis
Authors: Nagata Naoya , Furuya Kazuyuki , Oguro Nao , Nishiyama Daisuke , Kawai Kentaro , Yamamoto Noriko , Ohyabu Yuki , Satsukawa Masahiro , Miyakawa Motonori 
Published: November 2013

AbstractTetrahydroquinoline (THQ) was deemed to be a suitable scaffold for our nonsteroidal selective androgen receptor modulator (SARM) concept. We adapted the strategy of switching the antagonist function of cyano‐group‐containing THQ (CN‐THQ) to the agonist function and optimized CN‐THQ as an orally available drug candidate with suitable pharmacological and ADME profiles. Based on binding mode analyses and synthetic accessibility, we designed and synthesized a compound that possesses a para‐substituted aromatic ring attached through an amide linker. The long‐tail THQ derivative 6‐acetamido‐N‐(2‐(8‐cyano‐3a,4,5,9b‐tetrahydro‐3H‐cyclopenta[c]quinolin‐4‐yl)‐2‐methylpropyl)nicotinamide (1 d), which bears a para‐acetamide‐substituted aromatic group, showed an appropriate in vitro biological profile, as expected. We considered that the large conformational change at Trp741 of the androgen receptor (AR) and the hydrogen bond between 1 d and helix 12 of the AR could maintain the structure of the AR in its agonist form; indeed, 1 d displays strong AR agonistic activity. Furthermore, 1 d showed an appropriate in vivo profile for use as an orally available SARM, displaying clear tissue selectivity, with a separation between its desirable osteoanabolic effect on femoral bone mineral density and its undesirable virilizing effects on the uterus and clitoral gland in a female osteoporosis model.
Palladium Supported on Magnetic Core–Shell Nanoparticles: An Efficient and Reusable Catalyst for the Oxidation of Alcohols into Aldehydes and Ketones by Molecular Oxygen
Authors: Zhang Lei , Li Pinhua , Yang Jin , Wang Min , Wang Lei 
Published: November 2013

AbstractIn continuing our efforts to develop economical and ecofriendly synthetic protocols, we present a proline–palladium catalyst supported on magnetic nanoparticles (0.5 mol %) for oxidation by molecular oxygen. The supported Pd catalyst shows high activity in the oxidation of alcohols into the corresponding carbonyl compounds where easy catalyst recovery and excellent recycling efficiency are observed. It is possible to recover and reuse the grafted palladium catalysts at least eight times without significant loss of its catalytic activity.
Distributed method for cracking WPA/WPA2‐PSK on multi‐core CPU and GPU architecture
Authors: Yong‐lei Liu , Zhi‐gang Jin 
Published: November 2013

SummaryTo overcome the limitations of the existing brute force cracking method of Wi‐Fi Protected Access/Wi‐Fi Protected Access II (WPA/WPA2)‐pre‐shared key (PSK) based on single core CPU or one core of a multi‐core CPU, a new distributed multi‐core CPU and GPU parallel cracking method (DMCG) was first proposed. Colored Petri nets was used to validate the four‐way handshake protocol and proved that DMCG could successfully crack WPA/WPA2‐PSK. In DMCG, the PSK list was distributed to each PC reasonably using distributed technology. Multiple computing cores were made up of multi‐core CPU and GPU on single PC to crack in parallel. GPU contributed to the cracking speed improvement due to the strong computing power for intensive parallel tasks. Experimental results showed that DMCG improved the cracking speed by two orders of magnitude and would exhibit more notable advantages with high‐performance distributed system as the cracking speed improved by three or four orders of magnitude, compared with the computing power of one CPU core. An improved Amdahl's law was first proposed, by which the upper bound of the cracking speedup was analyzed. Aiming to the DMCG expansion of cloud computing based on GPU, a lightweight framework called Dandelion computing model was first proposed. Moreover, the analysis of the influences of the graphics card parameters on the cracking speed was processed, and accordingly, the decision support for choosing graphics card in DMCG based on analytic hierarchy process was provided. Finally, the performance optimization of DMCG was processed. Copyright © 2013 John Wiley & Sons, Ltd.
Myosin Va associates with mRNA in ribonucleoprotein particles present in myelinated peripheral axons and in the central nervous system
Authors: Calliari Aldo , Farías Joaquina , Puppo Agostina , Canclini Lucía , Mercer John A. , Munroe David , Sotelo José R. , Sotelo‐Silveira José R. 
Published: November 2013

ABSTRACTSorting of specific mRNAs to particular cellular locations and regulation of their translation is an essential mechanism underlying cell polarization. The transport of RNAs by kinesins and dyneins has been clearly established in several cell models, including neurons in culture. A similar role appears to exist in higher eukaryotes for the myosins. Myosin Va (Myo5a) has been described as a component of ribonucleoprotein particles (RNPs) in the adult rat nervous system and associated to ZBP1 and ribosomes in ribosomal periaxoplasmic plaques (PARPs), making it a likely candidate for mediating some aspects of RNA transport in neurons. To test this hypothesis, we have characterized RNPs containing Myo5a in adult brains of rats and mice. Microarray analysis of RNAs co‐immunoprecipitated with Myo5a indicates that this motor may associate with a specific subpopulation of neuronal mRNAs. We found mRNAs encoding α‐synuclein and several proteins with functions in translation in these RNPs. Immunofluorescence analyses of RNPs showed apparent co‐localization of Myo5a with ribosomes, mRNA and RNA‐binding proteins in discrete structures present both in axons of neurons in culture and in myelinated fibers of medullary roots. Our data suggest that PARPs include RNPs bearing the mRNA coding for Myo5a and are equipped with kinesin and Myo5a molecular motors. In conclusion, we suggest that Myo5a is involved in mRNA trafficking both in the central and peripheral nervous systems. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 382–396, 2014
Assessment of fat taste in individuals with and without anorexia nervosa
Authors: Schebendach Janet E. , Klein Diane A. , Mayer Laurel E.S. , Devlin Michael J. , Attia Evelyn , Walsh B. Timothy 
Published: November 2013

ABSTRACTObjectiveAvoidance of dietary fat is a highly characteristic eating behavior of individuals with anorexia nervosa (AN). To date, no study has determined whether these individuals are better able to perceive the fat content of foods than individuals without AN. The goal of this study was to compare blinded taste ratings of fat‐free, low fat, and regular cream cheese in patients with AN and in normal controls (NC).MethodAN (n = 25) and control (NC; n = 25) participants were presented with a series of nine cream cheese samples of three differing fat contents and asked to taste and rate each sample from very low to very high fat.ResultsRepeated measures ANOVA found no significant main effect of fat content and no interaction between fat content and diagnosis; however, a significant three‐way interaction between fat content, diagnosis, and trial was observed. Post hoc analysis revealed a significant fat content by trial interaction within the AN group, suggesting a significant trial effect for the fat‐free samples only with improving ability to detect fat‐free samples over repeated trials.DiscussionThe current study suggests that individuals with AN do not have a markedly greater ability to taste fat than NC, and that; therefore, fat avoidance is likely primarily based on cognitive factors. © 2013 Wiley Periodicals, Inc. (Int J Eat Disord 2014; 47:215–218)
Quaterphenylterpyridine: Synthesis and Metal‐Ion Complexation
Authors: Lee Young Hoon , Fuyuhiro Akira , Harrowfield Jack M. , Kim Yang , Sobolev Alexandre N. , Hayami Shinya 
Published: November 2013

AbstractA quaterphenylterpyridine ligand (qptpy) with the rodlike quaterphenyl unit attached in the 4′‐position has been synthesised by a Pd‐catalysed Suzuki cross‐coupling reaction. A crystal structure determination on the complex [Zn(qptpy)Cl2]·dmf (dmf = dimethylformamide) has shown the ligand to be bound in the expected N3‐tridentate manner to the essentially trigonal‐bipyramidal dichloro metal ion, with the quaterphenyl substituents involving a twisted array of the separate phenyl groups and the shortest contacts between aromatic groups involving just the polar terpyridine head groups to give an infinite, offset face‐to‐face (OFF) π‐stacking array. A comparison is made with the structures of the bis(ligand) complexes of Zn(ClO4)2 and Cd(ClO4)2 with the bromobiphenylterpyridine ligand (Brbptpy) synthesised as an intermediate for the formation of qptpy. A study of the absorption and emission spectra of qptpy and a range of its metal‐ion complexes has shown that the ligand provides a ratiometric fluorescence response for both ZnII and CdII.
Bi38 Oxocarboxylate Cages are Keplerates – Synthesis and Structural Characterization of Two Bi38 Oxocarboxylate Cages
Authors: Chandrasekhar Vadapalli , Metre Ramesh K. , Sahoo Dipankar 
Published: November 2013

AbstractThe reaction of 3,5‐dinitrobenzenecarboxylic acid with triphenylbismuth in a 1:1 stoichiometric ratio in toluene under reflux afforded two new Bi38 oxocarboxylate cages [Bi38(μ3‐O)22(μ4‐O)22(μ6‐O){3,5‐(NO2)2C6H3COO}20(OH)4(DMSO)16]·4DMSO·11H2O (1, DMSO = dimethyl sulfoxide) and [Bi38(μ3‐O)22(μ4‐O)22(μ6‐O){3,5‐(NO2)2C6H3COO}20(CH3COO)2(OH)2(DMF)10]·15DMF·20H2O (2, DMF = N,N‐dimethylformamide), which were obtained under different crystallization conditions. Compounds 1 and 2 are built from the coordination action of carboxylato, hydroxido, and oxido ligands and neutral solvent molecules. A detailed structural analysis of 1 reveals that the center of the core contains a {Bi6} octahedron, a Platonic polyhedron, which is encapsulated by another Platonic solid, viz., a {Bi8} cube. This entire assembly is further encapsulated by a truncated octahedral {Bi24} cage; the latter is an Archimedean solid. This structural arrangement of 1 classifies it along with Bi38 oxo cages as Keplerates, a structural family to which very few main‐group‐element‐containing compounds belong.
Disulfates from Low Temperature Synthesis in Ionic Liquids: (C5H6N)3Sm(S2O7)3 and (C5H6N)Bi(S2O7)2
Authors: Weiz Alexander , Bruns Jörn , Wickleder Mathias S. 
Published: November 2013

AbstractThe reactions of Bi(NO3)3·5H2O or Sm(NO3)3·6H2O with oleum (65 % SO3 in conc. H2SO4) and the pyridine (Py) complex Py·SO3 in the ionic liquid 1‐butyl‐3‐methylimidazolium hydrogen sulfate, [bmim][HSO4], yielded single crystals of (C5H6N)Bi(S2O7)2 and (C5H6N)3Sm(S2O7)3, respectively. In (C5H6N)3Sm(S2O7)3 the Sm3+ cations are ninefold coordinated by oxygen atoms in the form of a tricapped trigonal prism. The oxygen atoms belong to six chelating and six monodentate disulfate units. The anions connect the Sm3+ ions to chains according to 1∞[Sm(S2O7)6/2]3– along the crystallographic c‐axis. In (C5H6N)Bi(S2O7)2 the two crystallographic independent Bi3+ cations are in a distorted square‐prismatic oxygen coordination of eight oxygen atoms belonging to four chelating disulfate units. The connection of the Bi3+ ions leads to a corrugate layer according to 2∞[Bi(S2O7)4/2]–. In both compounds charge compensation is achieved by pyridinium cations (C5H6N)+, which are tilted towards each other and packed in a layered arrangement between the anionic units. Thermoanalytical investigations reveal the sesquioxide Sm2O3 as a residual product for the decomposition of (C5H6N)3Sm(S2O7)3.
Facile Solution‐Phase Synthesis of CuInSe2 Nanocrystals with Controlled Morphologies
Authors: Bai Tianyu , Li Feifei , Huang He , Wang Zhaorui , Shi Zhan , Li Chunguang , Wang Ge , Feng Shouhua 
Published: November 2013

AbstractThe morphology of CuInSe2 nanocrystals plays a key role in their functional properties. Achieving controllable morphology is significant for studying their structures and novel properties. Here, CuInSe2 nanocrystals with a trigonal‐pyramidal shape have successfully been synthesized by a facile solution‐phase method. The nanocrystals were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), and X‐ray photoelectron spectroscopy (XPS), etc. The morphological evolution of the CuInSe2 nanocrystals was illustrated by tuning the injection temperature of oleylamine‐selenium (OAm‐Se). In addition, CuInSe2 nanocrystals with spherical and ellipsoidal shapes were also obtained when copper stearate was used as the copper precursor.
Effect of Ligand Polarization on Asymmetric Structural Formation for Strongly Luminescent Lanthanide Complexes
Authors: Hasegawa Yasuchika , Ohkubo Tomoki , Nakanishi Takayuki , Kobayashi Atsushi , Kato Masako , Seki Tomohiro , Ito Hajime , Fushimi Koji 
Published: November 2013

AbstractThe effect of ligand polarization on the formation of strongly luminescent lanthanide complexes with asymmetric structures is described for the first time. The lanthanide complexes are composed of EuIII ions, three hexafluoroacetylacetonate (hfa) ligands, and two monodentate phosphine oxide ligands, namely, triphenylphosphine oxide (TPPO), p‐tolyldiphenylphosphine oxide (TPPO‐Me), tri‐p‐tolylphosphine oxide (TPPO‐3Me) or o‐phenoxyphenyldiphenylphosphine oxide (TPPO‐OPh). The luminescence properties of the EuIII complexes are characterized by their emission quantum yields, emission lifetimes, and their radiative (kr) and nonradiative (knr) rate constants. The EuIII complex with TPPO‐OPh ligands offers a markedly high emission quantum yield (72 % in [D6]acetone, 85 % in the solid state) owing to enhancement of the electric dipole transition and suppression of vibrational relaxation, which are directly related to kr and knr. The coordination geometries of the EuIII complexes are categorized by shape‐measure calculations. The EuIII complexes exhibit characteristic square‐antiprismatic or trigonal‐dodecahedral structures, depending on the ligand polarization. Strongly luminescent Eu(hfa)3(TPPO‐OPh)2 has an asymmetric dodecahedron structure. The formation of distorted dodecahedral structures with low vibrational frequencies for the enhancement of luminescence is elucidated in terms of the ligand polarization of the monodentate phosphine oxide ligands in the EuIII complexes.