bluuebunny/crossref_metadata_2025 huggingface dataset:
Constructing Hybrid Protein Zymogens through Protective Dendritic Assembly
Authors: Ng David Y. W. , Arzt Matthias , Wu Yuzhou , Kuan Seah Ling , Lamla Markus , Weil Tanja
Published: December 2013

The modulation of protein uptake and activity in response to physiological changes forms an integral part of smart protein therapeutics. We describe herein the self‐assembly of a pH‐responsive dendrimer shell onto the surface of active enzymes (trypsin, papain, DNase I) as a supramolecular protecting group to form a hybrid dendrimer–enzyme complex. The attachment is based on the interaction between boronic acid and salicyl hydroxamate, thus allowing the macromolecular assembly to respond to changes in pH between 5.0 and 7.4 in a highly reversible fashion. Catalytic activity is efficiently blocked in the presence of the dendrimer shell but is quantitatively restored upon shell degradation under acidic conditions. Unlike the native proteases, the hybrid constructs are shown to be efficiently taken up by A549 cells and colocalized in the acidic compartments. The programmed intracellular release of the proteases induced cytotoxicity, thereby uncovering a new avenue for precision biotherapeutics.
On Near‐controllability of Discrete‐time Upper‐triangular Bilinear Systems with Applications to Controllability
Authors: Tie Lin
Published: December 2013

Near‐controllability is defined for those systems that are uncontrollable but have a large controllable region. It is a property of nonlinear control systems introduced recently, and it has been demonstrated on two classes of discrete‐time bilinear systems. This paper studies near‐controllability of discrete‐time upper‐triangular bilinear systems, which are uncontrollable and are more general than the two classes mentioned. A necessary and sufficient condition for the systems in dimension two to be nearly controllable is presented, which covers the existing results. For the systems with high dimensions, necessary conditions and sufficient conditions of near‐controllability are provided, which generalize the existing results. In particular, the obtained near‐controllability results are applied to controllability of discrete‐time bilinear systems. An example also is given to demonstrate the effectiveness, which shows that the controllability problems of discrete‐time bilinear systems can be solved by near‐controllability.
Robust Tracking Control of Helicopters Using Backstepping with Disturbance Observers
Authors: He Yuebang , Pei Hailong , Sun Tairen
Published: December 2013

This paper addresses the robust and accurate trajectory tracking problem for unmanned helicopters in the presence of model uncertainties and external disturbances. First, the helicopter's model is simplified to a six‐degrees‐of‐freedom rigid body augmented with a simplified rotor dynamic model, with the model uncertainties and the external disturbances being treated as lumped unknown disturbances. Second, a nonlinear disturbance observer is designed to estimate this lumped disturbance. Then, a backstepping controller with disturbance compensation is designed to ensure robust and highly trajectory tracking. After that, the theoretical analysis of the efficiency of the designed disturbance observer‐based backstepping controller (Backstepping+DO) is shown by the Lyapunov theory. Finally, simulation results and conclusions are presented and discussed.
Circadian rhythms and mood: Opportunities for multi‐level analyses in genomics and neuroscience
Authors: Li Jun Z.
Published: December 2013

In the healthy state, both circadian rhythm and mood are stable against perturbations, yet they are capable of adjusting to altered internal cues or ongoing changes in external conditions. The dual demands of stability and flexibility are met by the collective properties of complex neural networks. Disruption of this balance underlies both circadian rhythm abnormality and mood disorders. However, we do not fully understand the network properties that govern the crosstalk between the circadian system and mood regulation. This puzzle reflects a challenge at the center of neurobiology, and its solution requires the successful integration of existing data across all levels of neural organization, from molecules, cells, circuits, network dynamics, to integrated mental function. This essay discusses several open questions confronting the cross‐level synthesis, and proposes that circadian regulation, and its role in mood, stands as a uniquely tractable system to study the causal mechanisms of neural adaptation.

Also watch the Video Abstract.

Editor's suggested further reading in BioEssays Major depressive disorder: A loss of circadian synchrony? Abstract.
A colorimetric and ratiometric fluorescent probe for sulfite based on an intramolecular cleavage mechanism
Authors: Hou Peng , Chen Song , Voitchovsky Kislon , Song Xiangzhi
Published: December 2013

A colorimetric and ratiometric fluorescent sulfite probe, the levulinate of 4‐hydroxynaphthalimide, was successfully synthesized from 4‐hydroxy‐naphthalimide and levulinic acid. Through sulfite‐mediated intramolecular cleavage, the probe was converted into 4‐hydroxynaphthalimide, which when excited at 450 nm, displayed a large Stokes shift due to the intramolecular charge transfer process. The probe exhibited high selectivity and sensitivity towards sulfite over other typical anionic species (F–, Cl–, Br–, I–, HPO42–, SO42–, NO3–, AcO–, ClO4–, HCO3–) in HEPES‐buffered solution (25 mm, pH 7.4, 50% acetonitrile, v/v). Copyright © 2013 John Wiley & Sons, Ltd.
A novel approach for using dielectric spectroscopy to predict viable cell volume (VCV) in early process development
Authors: Downey Brandon J. , Graham Lisa J. , Breit Jeffrey F. , Glutting Nathaniel K.
Published: December 2013

Online monitoring of viable cell volume (VCV) is essential to the development, monitoring, and control of bioprocesses. The commercial availability of steam‐sterilizable dielectric‐spectroscopy probes has enabled successful adoption of this technology as a key noninvasive method to measure VCV for cell‐culture processes. Technological challenges still exist, however. For some cell lines, the technique's accuracy in predicting the VCV from probe‐permittivity measurements declines as the viability of the cell culture decreases. To investigate the cause of this decrease in accuracy, divergences in predicted vs. actual VCV measurements were directly related to the shape of dielectric frequency scans collected during a cell culture. The changes in the shape of the beta dispersion, which are associated with changes in cell state, are quantified by applying a novel “area ratio” (AR) metric to frequency‐scanning data from the dielectric‐spectroscopy probes. The AR metric is then used to relate the shape of the beta dispersion to single‐frequency permittivity measurements to accurately predict the offline VCV throughout an entire fed‐batch run, regardless of cell state. This work demonstrates the possible feasibility of quantifying the shape of the beta dispersion, determined from frequency‐scanning data, for enhanced measurement of VCV in mammalian cell cultures by applying a novel shape‐characterization technique. In addition, this work demonstrates the utility of using changes in the shape of the beta dispersion to quantify cell health. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:479–487, 2014
Display of heterologous proteins on the Saccharomyces cerevisiae surface display system using a single constitutive expression vector
Authors: Sun Hui , Wang Tiantian , Zhang Jie , Liu Qing , Wang Longjiang , Chen Peipei , Wang Fangkun , Li Hongmei , Xiao Yihong , Zhao Xiaomin
Published: December 2013

In this study, we constructed a novel and simple yeast surface display system with a single expression vector. The newly established system uses a bidirectional expression vector carrying the AGA1 gene driven by the PGK1 promoter in one direction and the AGA2‐expression cassette driven by the TEF1 promoter in the reverse direction, and uses the geneticin, a G418‐resistant gene, as the selection marker for transformants. Because all the display elements are put into one expression vector, the new system is much simpler to use, and there is no need for any genetic modification of the host strains; therefore, the new system can be used in wild type as well as laboratory strains of Saccharomyces cerevisiae. The display efficiency of heterologous proteins using the new system has been confirmed by displaying enhanced green fluorescent protein and Eimeria tenella (a chicken protozoan parasite) microneme protein2 (EtMic2) on several S. cerevisiae strains. We also tested the new system with an aga2 mutant strain of S. cerevisiae. The results indicate that the native expressed Aga2 protein has no effect on the display efficiency of heterologous proteins. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:443–450, 2014
Protein Engineering of the Antitumor Enzyme PpADI for Improved Thermal Resistance
Authors: Zhu Leilei , Cheng Feng , Piatkowski Victoria , Schwaneberg Ulrich
Published: December 2013

Arginine deiminase (ADI, EC 3.5.3.6) is a potential antitumor drug for the treatment of arginine‐auxotrophic tumors such as hepatocellular carcinomas (HCCs) and melanomas. Studies in human lymphatic leukemia cell lines have confirmed the anti‐angiogenic activity of ADI. Activity and thermal resistance limit the efficacy of ADI in treatment of auxotrophic tumors. Previously, we reengineered ADI fromPseudomonas plecoglossicida(PpADI) for improved activity under physiological conditions (37 °C, PBS buffer, pH 7.4) by two rounds of directed evolution and combination of beneficial substitutions through site‐directed mutagenesis. The best variant, PpADI M6 (K5T/D38H/D44E/A128T/E296K/H404R), showed a 64.7‐fold improvement inkcatvalue and a 37.6 % decreasedS0.5value under physiological conditions. However, M6 lost rapidly its activity (half‐life of ∼2 days at 37 °C). Here we report the re‐engineering of PpADI M6 for improved thermal resistance by directed evolution in order to increase its half‐life under physiological conditions. Directed evolution and recombination of the two most beneficial positions yielded variant PpADI M9 (K5T/D38H/D44E/A128T/V140L/E296K/F325L/H404R), for which theTmvalue increased from 47 (M6) to 54 °C (M9); this corresponds to an increased half‐life from ∼2 days (M6) to ∼3.5 days (M9) under physiological conditions. Structure analysis of the homology model of M9 showed that the beneficial substitutions V140L and F325L likely promote the formation of tetrameric PpADI, which has greater thermal resistance than dimeric PpADI.
Influence of Ph2PN(R)P(Ph)N(R)H (R=c‐Hex, iPr) Ligand Substituents, Modifier, and Process Parameters on Reaction Kinetics of a Chromium‐based Catalyst for the Selective Trimerization of Ethylene
Authors: Heinig Stefan , Wöhl Anina , Müller Wolfgang , Al‐Hazmi Mohammed H. , Müller Bernd H. , Peulecke Normen , Rosenthal Uwe
Published: December 2013

The influence of ligand substituents on a homogeneous, highly selective catalyst system for the ethylene trimerization to 1‐hexene, consisting of chromium(III)acetylacetonate as a chromium source, tetraphenylphosphonium chloride ([Ph4P]Cl) or dodecyltrimethylammonium chloride ([CH3(CH2)11N(CH3)3]Cl) as a modifier and chlorine source, Ph2PN(iPr)P(Ph)N(iPr)H (L0) as a ligand (Ph=phenyl, iPr=isopropyl), and triethylaluminum as an activator, was investigated. It was shown that the phosphonium or ammonium salts act as both chlorine source and as modifier for the activator triethylaluminum. Additionally, a systematic parameter study using Ph2PN(c‐Hex)P(Ph)N(c‐Hex)H (L1) as the ligand (c‐Hex=cyclohexyl) was performed and important performance figures for catalyst systems using L0 and L1 ligands, respectively, were compared under different reaction conditions. As a result, both catalyst systems demonstrate very similar kinetics at identical ethylene pressures, temperatures, and ligand concentrations. Additionally, the influence of the modifiers on the performance of the catalyst systems at different ethylene pressures and temperatures was studied in detail. The results suggest that the modifier has a greater influence on the reaction mechanism than expected. Moreover, the influence of the modifier on the catalytic performance was found to be more significant than the impact of the ligand’s chemical nature.
Highly Active Small Palladium Clusters Supported on Ferric Hydroxide for Carbon Monoxide‐Tolerant Hydrogen Oxidation
Authors: Qiao Botao , Lin Jian , Li Lin , Wang Aiqin , Liu Jingyue , Zhang Tao
Published: December 2013

Proton‐exchange membrane fuel cells have been regarded as one of the most promising candidates for efficient energy conversion. However, the CO poisoning of the anode and the scarcity of the Pt metal are two major barriers to their commercialization. Development of CO‐tolerant Pd electrocatalysts is considered to be a plausible approach to overcome these problems. Herein we report that for the CO‐tolerant H2 oxidation, sub‐2‐nm size Pd clusters as well as single atoms, supported on FeOx nanocrystallites, are highly active and durable at a wide temperature range of 20–120 °C. Experimental data demonstrated that CO preferentially adsorbs on these small Pd clusters or single atoms linearly, resulting in weakened CO binding and enhanced H2 competitive adsorption. Therefore, FeOx‐supported small Pd clusters or single atoms provide a higher CO‐tolerant performance. This finding may offer a new strategy to develop CO‐tolerant Pd‐based electrodes.
Efficient Copper‐Catalyzed Direct Intramolecular Aminotrifluoromethylation of Unactivated Alkenes with Diverse Nitrogen‐Based Nucleophiles
Authors: Lin Jin‐Shun , Xiong Ya‐Ping , Ma Can‐Liang , Zhao Li‐Jiao , Tan Bin , Liu Xin‐Yuan
Published: December 2013

A mild, convenient, and step‐economical intramolecular aminotrifluoromethylation of unactivated alkenes with a variety of electronically distinct, nitrogen‐based nucleophiles in the presence of a simple copper salt catalyst, in the absence of extra ligands, is described. Many different nitrogen‐based nucleophiles (e.g., basic primary aliphatic and aromatic amines, sulfonamides, carbamates, and ureas) can be employed in this new aminotrifluoromethylation reaction. The aminotrifluoromethylation process allows straightforward access to diversely substituted CF3‐containing pyrrolidines or indolines, in good to excellent yields, through a direct difunctionalization strategy from the respective acyclic starting materials. Mechanistic studies were conducted and a plausible mechanism was proposed.
Dispersible Carbon Nanotubes
Authors: Soulié‐Ziakovic Corinne , Nicolaÿ Renaud , Prevoteau Alexandre , Leibler Ludwik
Published: December 2013

A method is proposed to produce nanoparticles dispersible and recyclable in any class of solvents, and the concept is illustrated with the carbon nanotubes. Classically, dispersions of CNTs can be achieved through steric stabilization induced by adsorbed or grafted polymer chains. Yet, the surface modification of CNTs surfaces is irreversible, and the chemical nature of the polymer chains imposes the range of solvents in which CNTs can be dispersed. To address this limitation, supramolecular bonds can be used to attach and to detach polymer chains from the surface of CNTs. The reversibility of supramolecular bonds offers an easy way to recycle CNTs as well as the possibility to disperse the same functional CNTs in any type of solvent, by simply adapting the chemical nature of the stabilizing chains to the dispersing medium. The concept of supramolecular functionalization can be applied to other particles, for example, silica or metal oxides, as well as to dispersing in polymer melts, films or coatings.
ChemInform Abstract: Magnesium Double Nitride Mg3GaN3 as New Host Lattice for Eu2+ Doping: Synthesis, Structural Studies, Luminescence, and Band‐Gap Determination.
Authors: Hintze Frauke , Johnson Neil W. , Seibald Markus , Muir David , Moewes Alexander , Schnick Wolfgang
Published: December 2013

Eu‐doped Mg3GaN3 (I) and binary nitride Mg3N2 (II) are prepared by reaction of the corresponding metals with NaN3 in a sodium flux (welded Ta ampules, 760 °C, 2 d; cooling to 200 °C with a rate of 0.06 °C/min).
ChemInform Abstract: Noncentrosymmetric Cubic CsCdBO3 with Bichromophore.
Authors: Yu Hongwei , Wu Hongping , Pan Shilie , Zhang Bingbing , Wen Ming , Yang Zhihua , Li Hongyi , Jiang Xiangzhan
Published: December 2013

Single crystals of the title compound are obtained from a molten mixture of Cs2CO3, CdO, and H3BO3 (1:1:2 molar ratio, Pt crucible, 800 °C, 10 h).
ChemInform Abstract: Solid State Complex Chemistry: Formation, Structure, and Properties of Homoleptic Tetracyanamidogermanates RbRE[Ge(CN2)4] (RE: La, Pr, Nd, Gd).
Authors: Kalmutzki Markus , Enseling David , Wren John E. C. , Kroeker Scott , Terskikh Victor V. , Juestel Thomas , Meyer H.‐Juergen
Published: December 2013

RbLn[Ge(CN2)4] (I) (Ln: La, Pr, Nd, Gd) and RbLn[Si(CN2)4] (II) are prepared by solid state metathesis reaction of stoichiometric mixtures of LnCl3, Rb2[GeF6] or Rb2[SiF6], and Li2(CN2) (evacuated silica ampoule, for (I): 450 °C, 1 d; for (II): 550 °C, 2 d).
ChemInform Abstract: A Novel POM‐Based Inorganic Porous Framework: Synthesis, Structure and Properties.
Authors: Sun Yingying , Lu Jing , Li Dacheng , Dou Jianmin
Published: December 2013

(H2en)[Mn3P4Mo4O28] is hydrothermally synthesized from a mixture of (NH4)6Mo7O24, Mn(OAc)2, Dy(OAc)3, en, H3PO4, and H2O (pH 5, autoclave, 180 °C, 5 d; 75% yield).
ChemInform Abstract: {Mo24Fe12} Macrocycles: Anion Templation with Large Polyoxometalate Guests.
Authors: Fang Xikui , et al. et al.
Published: December 2013

The ability of large polyoxometalate anions to act as templating agents is demonstrated with the formation of compounds (V) and (VII).
ChemInform Abstract: A Survey of Sulfide Ligands for Allylic C—H Oxidations of Terminal Olefins.
Authors: Le Chi , Kunchithapatham Kamala , Henderson William H. , Check Christopher T. , Stambuli James P.
Published: December 2013

Screening a 37‐membered library of thioether ligands has shown that tetrahydrothiophene is a highly reactive and selective ligand for Pd‐catalyzed allylic C—H oxidation reactions.
ChemInform Abstract: Catalyst‐Controlled Divergent C—H Functionalization of Unsymmetrical 2‐Aryl Cyclic 1,3‐Dicarbonyl Compounds with Alkynes and Alkenes.
Authors: Dooley Johnathon D. , Chidipudi Suresh Reddy , Lam Hon Wai
Published: December 2013

The oxidative annulation of alkynes and alkenes with unsymmetrical 2‐aryl cyclic 1,3‐dicarbonyl compounds is achieved with high site selectivity using palladium or ruthenium catalysis.
ChemInform Abstract: Type III‐B Rotaxane Dendrimers.
Authors: Ho Watson K.‐W. , Lee Siu‐Fung , Wong Chi‐Hin , Zhu Xiao‐Ming , Kwan Chak‐Shing , Chak Chun‐Pong , Mendes Paula M. , Cheng Christopher H. K. , Leung Ken Cham‐Fai
Published: December 2013

Novel type III‐B dendrimers are synthesized via a modified copper‐catalyzed alkyne—azide cycloaddition, a Glaser—Hay′s acetylenic oxidative homocoupling, and an amide formation.
ChemInform Abstract: Enantioselective Synthesis of anti‐β‐Amido‐α‐hydroxy Esters via Asymmetric Transfer Hydrogenation Coupled with Dynamic Kinetic Resolution.
Authors: Villacrez Marvin , Somfai Peter
Published: December 2013

A rapid and straightforward diastereo‐ and enantioselective synthesis of anti‐β‐amido‐α‐hydroxy esters (II) is achieved with the aid of a simply prepared chiral ruthenium catalyst.
ChemInform Abstract: K3PO4—KOH Mixture as Efficient Reagent for the Deprotection of 4‐Aryl‐2‐methyl‐3‐butyn‐2‐ols to Terminal Acetylenes.
Authors: Smeyanov Alexey , Schmidt Andreas
Published: December 2013

An efficient and fast method for the synthesis of terminal acetylenes (II) (18 examples) by deprotection of the title butynols (I) is developed.
ChemInform Abstract: Enantioselective Alkylation of Aldehydes Using Functionalized Alkylboron Reagents Catalyzed by a Chiral Titanium Complex.
Authors: Kumar Ravindra , Kawasaki Hiroki , Harada Toshiro
Published: December 2013

An octahydro‐BINOL derived titanium complex is used to catalyze the addition reaction of alkylboron reagents, generated in situ from terminal olefin precursors by hydroboration, to aldehydes to provide secondary alcohols with high enantioselectivities.
ChemInform Abstract: Microwave‐Assisted Convenient Synthesis of α,β‐Unsaturated Esters and Ketones via Aldol‐Adduct Elimination.
Authors: Suman Pathi , Rao Rayala Nageswara , Raju Bhimapaka China
Published: December 2013

Various fluorinated 3‐oxo ester and 1,3‐diketones are reacted with aldehydes (I) in the presence of piperidine to afford title compounds such as (III) and (V) (34 example).
ChemInform Abstract: Transformation of N‐Alkylated Anilines to N‐Aryloxamates.
Authors: Zhu Xiao‐He , Zhang Xin , Xin Hong‐Xing , Yan Hong
Published: December 2013

A novel approach to title compounds (III) using 2‐diazoacetoacetate (II) as alkylating agent and a Rh‐complex as a catalyst is reported.
ChemInform Abstract: Regioselective Carbonylation of trans‐Disubstituted Epoxides to β‐Lactones: A Viable Entry into syn‐Aldol‐Type Products.
Authors: Mulzer Michael , Whiting Bryan T. , Coates Geoffrey W.
Published: December 2013

The new two catalysts show high and opposing selectivities in the title reaction.
ChemInform Abstract: Construction of Vicinal Tertiary and All‐Carbon Quaternary Stereocenters via Ir‐Catalyzed Regio‐, Diastereo‐, and Enantioselective Allylic Alkylation and Applications in Sequential Pd Catalysis.
Authors: Liu Wen‐Bo , Reeves Corey M. , Virgil Scott C. , Stoltz Brian M.
Published: December 2013

A highly regio‐, diastereo‐, and enantioselective Ir‐catalyzed α‐allylic alkylation of cyclic β‐ketoesters is presented.
ChemInform Abstract: Direct Oxidative Conversion of Methylarenes into Aromatic Nitriles.
Authors: Tsuchiya Daisuke , Kawagoe Yuhsuke , Moriyama Katsuhiko , Togo Hideo
Published: December 2013

Two cyanide‐free and transition‐metal‐free one‐pot procedures are presented for the synthesis of aromatic nitriles from methylarenes using NBS or 1,3‐dibromo‐5,5‐dimethylhydantoin as the oxidant.
ChemInform Abstract: Selective Oxidation of Alcohols to Esters Using Heterogeneous Co3O4—N@C Catalysts under Mild Conditions.
Authors: Jagadeesh Rajenahally V. , Junge Henrik , Pohl Marga‐Martina , Radnik Joerg , Brueckner Angelika , Beller Matthias
Published: December 2013

Co3O4 supported on carbon‐nitrogen material represents an excellent catalyst for the selective oxidation of alcohols to esters using benign oxygen as the final oxidant.
ChemInform Abstract: AgF‐Mediated Homocoupling Reaction of Trialkoxy Aryl Silanes
Authors: Luo Hai‐Qing , Dong Wen
Published: December 2013

as a direct entry to synthesize symmetrical biaryls (II) (11 examples)
ChemInform Abstract: Asymmetric Epoxidation of Alkenes Catalyzed by a Porphyrin‐Inspired Manganese Complex.
Authors: Dai Wen , Li Jun , Li Guosong , Yang Hua , Wang Lianyue , Gao Shuang
Published: December 2013

It is demonstrated that an optically active bisoxazoline ligand in combination with Mn(OTf)2 efficiently catalyzes the oxidation of various olefins with hydrogen peroxide to give epoxides with excellent enantioselectivities.
ChemInform Abstract: N‐Heterocyclic Carbene Catalyzed Annulation of Benzofuran‐2,3‐diones and Enals: A Concise Synthesis of Spiro‐bis‐lactone.
Authors: Wang Ze‐Dong , Wang Feng , Li Xin , Cheng Jin‐Pei
Published: December 2013

The regioselectivity of the formation of spiro‐bis‐lactones from benzofuran‐2,3‐diones and α,β‐unsaturated β‐aryl‐substituted aldehydes is investigated with different N‐heterocyclic carbene catalysts.
ChemInform Abstract: Platinum‐Catalyzed Tandem Indole Annulation/Arylation for the Synthesis of Diindolylmethanes and Indolo[3,2‐b]carbazoles.
Authors: Shu Dongxu , Winston‐McPherson Gabrielle N. , Song Wangze , Tang Weiping
Published: December 2013

The scope of different indoles and propargylic ethers is examined for the tandem annulation/arylation cascade reaction.
ChemInform Abstract: Development of a Tailor‐Made Bis(oxazolidine)pyridine—Metal Catalyst for the [3 + 2] Cycloaddition of Azomethine Imines with Propiolates.
Authors: Arai Takayoshi , Ogino Yuta , Sato Toru
Published: December 2013

A series of bis(oxazolidine)pyridine ligands is designed and applied in the title reaction.
ChemInform Abstract: Starch—Sulfuric Acid (SSA) as Catalyst for a One‐Pot Synthesis of 1,5‐Diaryl‐1H‐pyrazoles.
Authors: Hatamjafari Farhad
Published: December 2013

Starch‐supported sulfuric acid acts as an efficient and environmentally friendly catalyst for the regioselective synthesis of new pyrazoles (III) via condensation of Baylis—Hillman adducts (I) with phenylhydrazine.
ChemInform Abstract: Highly Regioselective Synthesis of 2,4,5‐(Hetero)aryl Substituted Oxazoles by Intermolecular [3 + 2] Cycloaddition of Unsymmetrical Internal Alkynes.
Authors: Chatzopoulou Elli , Davies Paul W.
Published: December 2013

The applied Au‐catalyst is prepared in one step.
ChemInform Abstract: Nitro‐Methyl Redox Coupling: Efficient Approach to 2‐Hetarylbenzothiazoles from 2‐Halonitroarene, Methylhetarene, and Elemental Sulfur.
Authors: Nguyen Thanh Binh , Ermolenko Ludmila , Al‐Mourabit Ali
Published: December 2013

A simple, straightforward, and atom‐economic multicomponent synthesis of different substituted benzothiazoles from readily available starting materials is developed.
ChemInform Abstract: Bifunctional Building Blocks in the Ugi‐Azide Condensation Reaction: A General Strategy Toward Exploration of New Molecular Diversity.
Authors: Gunawan Steven , Hulme Christopher
Published: December 2013

Ugi‐azide reaction of tethered aldo/keto—acids/esters followed by a ring closing step opens access to a variety of complex lactam—tetrazoles.
ChemInform Abstract: An Efficient Synthesis of Novel 3‐Hydroxy‐12‐arylbenzo[a]xanthen‐11‐ones and 5,12‐Diarylxantheno[2,1‐a]xanthene‐4,12‐diones Using pTSA in [bmim]BF4.
Authors: Yadav Sneha , Nand Bhaskara , Khurana Jitender M.
Published: December 2013

Simple, efficient and environmentally benign syntheses of novel xanthene derivatives via one‐pot multicomponent condensation reactions are developed.
ChemInform Abstract: Synthesis of Functionalized Isoquinolin‐1(2H)‐ones by Copper‐Catalyzed α‐Arylation of Ketones with 2‐Halobenzamides.
Authors: Shi Yan , Zhu Xuebin , Mao Haibin , Hu Hongwen , Zhu Chengjian , Cheng Yixiang
Published: December 2013

A novel and efficient method for the synthesis of the title compounds through sequential α‐arylation and dehydrative cyclization processes is developed tolerating broad range of substituents.
ChemInform Abstract: Pd‐Catalyzed Tandem C—H Azidation and N—N Bond Formation of Arylpyridines: A Direct Approach to Pyrido[1,2‐b]indazoles.
Authors: Zheng Qing‐Zhong , Feng Peng , Liang Yu‐Feng , Jiao Ning
Published: December 2013

A novel Pd‐catalyzed nitrogenation of ortho‐aryl substituted pyridines is developed using NaN3 as the N‐atom source.
ChemInform Abstract: Superacid‐Promoted Cyclodehydration Leading to the Imidazo[2,1‐a]isoquinoline Ring System.
Authors: Kethe Anila , Naredla Rajasekhar Reddy , Klumpp Douglas A.
Published: December 2013

A mechanism for the title reaction is proposed involving dicationic intermediates.
ChemInform Abstract: Urea‐Catalyzed Construction of Oxazinanes
Authors: Hardman Andrea M. , So Sonia S. , Mattson Anita E.
Published: December 2013

by cycloaddition reaction of nitrocyclopropane carboxylates and nitrones
ChemInform Abstract: Synthesis of Silanes and Germanes with Polyunsaturated Aliphatic Substituents
Authors: Yarosh N. O. , Zhilitskaya L. V. , Voronkov M. G.
Published: December 2013

via hydrosilylation of alkynes followed by subsequent treatment with ethynylmagnesium bromide
ChemInform Abstract: Direct Transformation of Amides into α‐Amino Phosphonates via a Reductive Phosphination Process.
Authors: Gao Yuzhen , Huang Zhongbin , Zhuang Rongqiang , Xu Jian , Zhang Pengbo , Tang Guo , Zhao Yufen
Published: December 2013

A first general one pot method for the reductive phosphination of amides using Schwartz′s reagent is presented.
ChemInform Abstract: Chiral α‐Amino Phosphonates via Rhodium‐Catalyzed Asymmetric 1,4‐Addition Reactions.
Authors: Lefevre Nicolas , Brayer Jean‐Louis , Folleas Benoit , Darses Sylvain
Published: December 2013

A straightforward method for the synthesis of α‐aminophosphonates from dehydroaminophosphonates (I) and (IV) is developed using a Rh‐catalyzed 1,4‐addition of arenetrifluoroborates in the presence of (S)‐difluorophos as chiral ligand.
ChemInform Abstract: Arvestolides A—C (I), (II), and (III), New Rare Sesquiterpenes from the Aerial Parts of Artemisia vestita.
Authors: Tian Shuaihua , Chai Xingyn , Zan Ke , Zeng Kewu , Guo Xiaoyu , Jiang Yong , Tu Pengfei
Published: December 2013

The isolated arvestolide (II) shows a moderate inhibition effect on lipopolysaccharide‐induced nitric oxide production in BV‐2 microglial cells.
ChemInform Abstract: Reagent Controlled β‐Specific Dehydrative Glycosylation Reactions with 2‐Deoxy‐sugars.
Authors: Issa John Paul , Lloyd Dina , Steliotes Emily , Bennett Clay S.
Published: December 2013

It is demonstrated that 2‐deoxysugar hemiacetals react with 1‐tosyl‐4‐nitroimidazol to generate intermediates which react with S‐ or O‐nucleophiles to give β‐glycosides exclusively.
ChemInform Abstract: Spiro Fused Diterpene—Indole Alkaloids from a Creek‐Bottom‐Derived Aspergillus terreus.
Authors: Cai Shengxin , Du Lin , Gerea Alexandra L. , King Jarrod B. , You Jianlan , Cichewicz Robert H.
Published: December 2013

Teraspiridoles A‐D (Ia,b, IIa,b) are isolated from the title fungus.
ChemInform Abstract: Enantioselective Total Synthesis of (‐)‐Citrinadin A and Revision of Its Stereochemical Structure.
Authors: Bian Zhiguo , Marvin Christopher C. , Martin Stephen F.
Published: December 2013

For the first time, the synthesis of title compound (I) is accomplished in 20 steps from commercially available materials.
ChemInform Abstract: Reactions of Acid Chlorides/Ketenes with 2‐Substituted 4,5‐Dihydro‐4,4‐dimethyl‐1,3‐thiazoles: Formation of Penam Derivatives.
Authors: Shi Junxing , Linden Anthony , Heimgartner Heinz
Published: December 2013

Addition reactions of acid chlorides (II) and (V) to dihydro‐4,4‐dimethyl‐5‐methylthio‐thiazoles (I), (IV), and (IX) are studied.
ChemInform Abstract: A Novel Production Method for Nitridosilicate‐Type Phosphors.
Authors: Cakmak Hasan , Jansen Martin
Published: December 2013

M2‐xEuxSi5N8 (M: Ca, Sr, Eu) orange‐to‐red phosphors for white‐LED applications are prepared by reacting SiCl4 with liquid NH3 in which Ca, Sr, or Eu metals are dissolved, or Eu[N(SiMe3)2]3 is suspended.
ChemInform Abstract: Synthesis of Wurtzite Cu2ZnGeSe4 Nanocrystals and Their Thermoelectric Properties.
Authors: Xue Ding‐Jiang , Jiao Fei , Yan Hui‐Juan , Xu Wei , Zhu Daoben , Guo Yu‐Guo , Wan Li‐Jun
Published: December 2013

The title nanocrystals with an unusual wurtzite structure are synthesized by injection of an oleylamine solution of diphenyl diselenide into a mixture of Cu(OAc)2, Zn(OAc)2, GeI4, and oleylamine at 230 °C.
ChemInform Abstract: A Study on the Mechanism for the Interaction of Light with Noble Metal‐Metal Oxide Semiconductor Nanostructures for Various Photophysical Applications
Authors: Kochuveedu Saji Thomas , Jang Yoon Hee , Kim Dong Ha
Published: December 2013

Review: 223 refs.
ChemInform Abstract: Catalytic Enantioselective Reductive Desymmetrization of Achiral and meso Compounds
Authors: Fernandez‐Perez Hector , Etayo Pablo , Lao Joan R. , Nunez‐Rico Jose L. , Vidal‐Ferran Anton
Published: December 2013

Review: 93 refs.
ChemInform Abstract: Generation of Structural Diversity in Polyphosphazenes
Authors: Allcock Harry R.
Published: December 2013

Review: 59 refs.
ChemInform Abstract: Co3O4 Nanocrystals and Co3O4—MOx Binary Oxides for CO, CH4 and VOC Oxidation at Low Temperatures: A Review
Authors: Liotta Leonarda Francesca , Wu Hongjing , Pantaleo Giuseppe , Venezia Anna Maria
Published: December 2013

Review: 82 refs.
ChemInform Abstract: Electrophilic Activation of Acetylene Compounds in Broensted Superacids. Reactions of Vinyl Type Cations
Authors: Vasilyev A. V.
Published: December 2013

Review: 89 refs.
ChemInform Abstract: Bromination of Organic Substrates with Special Reference to Green Chemistry
Authors: Nath Jayashree , Sarmah Bhaskar J. , Patel Bhisma K.
Published: December 2013

Review: 195 refs.
ChemInform Abstract: Coordination Polymers and Metal‐Organic Frameworks Derived from 4,4′‐Dicarboxy‐2,2′‐bipyridine and 4,4′,6,6′‐Tetracarboxy‐2,2′‐bipyridine Ligands: A Personal Perspective
Authors: Kruger Paul E.
Published: December 2013

Review: 68 refs.
ChemInform Abstract: A Journey from Supramolecular Chemistry to Nanoscale Networks
Authors: Constable Edwin C.
Published: December 2013

Review: 32 refs.
ChemInform Abstract: Metal Ion Transport Across Metal‐organic Pyrogallol[4]arene‐based Nanocapsules
Authors: Kumari Harshita , Jin Ping , Deakyne Carol A. , Atwood Jerry L.
Published: December 2013

Review: 57 refs.
ChemInform Abstract: Bioprocessing as a Route to Food Ingredients: An Introduction
Authors: Wood B. J. B.
Published: December 2013

Review: 19 refs.
ChemInform Abstract: Nanoparticles of Molecule‐Based Conductors
Authors: de Caro Dominique , et al. et al.
Published: December 2013

Review: 48 refs.
ChemInform Abstract: Array Sensing Using Optical Methods for Detection of Chemical and Biological Hazards
Authors: Diehl Katharine L. , Anslyn Eric V.
Published: December 2013

Review: 48 refs.
ChemInform Abstract: Optical Sensor Arrays for Chemical Sensing: The Optoelectronic Nose
Authors: Askim Jon R. , Mahmoudi Morteza , Suslick Kenneth S.
Published: December 2013

Review: 313 refs.
Physical (in)activity‐dependent structural plasticity in bulbospinal catecholaminergic neurons of rat rostral ventrolateral medulla
Authors: Mischel Nicholas A. , Llewellyn‐Smith Ida J. , Mueller Patrick J.
Published: December 2013

Increased activity of the sympathetic nervous system is thought to play a role in the development and progression of cardiovascular disease. Recent work has shown that physical inactivity versus activity alters neuronal structure in brain regions associated with cardiovascular regulation. Our physiological studies suggest that neurons in the rostral ventrolateral medulla (RVLM) are more responsive to excitation in sedentary versus physically active animals. We hypothesized that enhanced functional responses in the RVLM may be due, in part, to changes in the structure of RVLM neurons that control sympathetic activity. We used retrograde tracing and immunohistochemistry for tyrosine hydroxylase (TH) to identify bulbospinal catecholaminergic (C1) neurons in sedentary and active rats after chronic voluntary wheel‐running exercise. We then digitally reconstructed their cell bodies and dendrites at different rostrocaudal levels. The dendritic arbors of spinally projecting TH neurons from sedentary rats were more branched than those of physically active rats (P < 0.05). In sedentary rats, dendritic branching was greater in more rostral versus more caudal bulbospinal C1 neurons, whereas, in physically active rats, dendritic branching was consistent throughout the RVLM. In contrast, cell body size and the number of primary dendrites did not differ between active and inactive animals. We suggest that these structural changes provide an anatomical underpinning for the functional differences observed in our in vivo studies. These inactivity‐related structural and functional changes may enhance the overall sensitivity of RVLM neurons to excitatory stimuli and contribute to an increased risk of cardiovascular disease in sedentary individuals. J. Comp. Neurol. 522:499–513, 2014. © 2013 Wiley Periodicals, Inc.
Spino‐olivary projections in the rat are anatomically separate from postsynaptic dorsal column projections
Authors: Flavell Charlotte R. , Cerminara Nadia L. , Apps Richard , Lumb Bridget M.
Published: December 2013

The gracile nucleus (GN) and lateral part of rostral dorsal accessory olive (rDAO) are important relays for indirect, postsynaptic dorsal column, and direct ascending pathways, respectively, that terminate as climbing fibers in the “hindlimb‐receiving” parts of the C1 and C3 zones in the cerebellar cortex. While the spinal cells of origin of that project to GN and rDAO are from largely separate territories in the spinal cord, previous studies have indicated that there could be an area of overlap between these two populations in the medial dorsal horn. Given the access of these two ascending tracts to sensory (thalamic) versus sensorimotor (precerebellar) pathways, the present study therefore addresses the important question of whether or not individual neurons have the potential to contribute axons to both ascending pathways. A double‐fluorescent tracer strategy was used in rats (red Retrobeads and Fluoro‐Ruby or green Retrobeads and Fluoro‐Emerald) to map the spatial distribution of cells of origin of the two projections in the lumbar spinal cord. The two pathways were found to receive input from almost entirely separate territories within the lumbar cord (levels L3–L5). GN predominantly receives input from lamina IV, while rDAO receives its input from three cell populations: medial laminae V–VI, lateral lamina V, and medial laminae VII–VIII. Cells that had axons that branched to supply both GN and rDAO represented only about 1% of either single‐labeled cell population. Overall, the findings therefore suggest functional independence of the two ascending pathways. J. Comp. Neurol. 522:2179–2190, 2014. © 2013 Wiley Periodicals, Inc.
Bidirectional global spontaneous network activity precedes the canonical unidirectional circuit organization in the developing hippocampus
Authors: Shi Yulin , Ikrar Taruna , Olivas Nicholas D. , Xu Xiangmin
Published: December 2013

Spontaneous network activity is believed to sculpt developing neural circuits. Spontaneous giant depolarizing potentials (GDPs) were first identified with single‐cell recordings from rat CA3 pyramidal neurons, but here we identify and characterize a large‐scale spontaneous network activity we term global network activation (GNA) in the developing mouse hippocampal slices, which is measured macroscopically by fast voltage‐sensitive dye imaging. The initiation and propagation of GNA in the mouse is largely GABA‐independent and dominated by glutamatergic transmission via AMPA receptors. Despite the fact that signal propagation in the adult hippocampus is strongly unidirectional through the canonical trisynaptic circuit (dentate gyrus [DG] to CA3 to CA1), spontaneous GNA in the developing hippocampus originates in distal CA3 and propagates both forward to CA1 and backward to DG. Photostimulation‐evoked GNA also shows prominent backward propagation in the developing hippocampus from CA3 to DG. Mouse GNA is strongly correlated to electrophysiological recordings of highly localized single‐cell and local field potential events. Photostimulation mapping of neural circuitry demonstrates that the enhancement of local circuit connections to excitatory pyramidal neurons occurs over the same time course as GNA and reveals the underlying pathways accounting for GNA backward propagation from CA3 to DG. The disappearance of GNA coincides with a transition to the adult‐like unidirectional circuit organization at about 2 weeks of age. Taken together, our findings strongly suggest a critical link between GNA activity and maturation of functional circuit connections in the developing hippocampus. J. Comp. Neurol. 522:2191–2208, 2014. © 2013 Wiley Periodicals, Inc.
Left atrial ligation alters intracardiac flow patterns and the biomechanical landscape in the chick embryo
Authors: Kowalski William J. , Teslovich Nikola C. , Menon Prahlad G. , Tinney Joseph P. , Keller Bradley B. , Pekkan Kerem
Published: December 2013

Background: Hypoplastic left heart syndrome (HLHS) is a major human congenital heart defect that results in single ventricle physiology and high mortality. Clinical data indicate that intracardiac blood flow patterns during cardiac morphogenesis are a significant etiology. We used the left atrial ligation (LAL) model in the chick embryo to test the hypothesis that LAL immediately alters intracardiac flow streams and the biomechanical environment, preceding morphologic and structural defects observed in HLHS. Results: Using fluorescent dye injections, we found that intracardiac flow patterns from the right common cardinal vein, right vitelline vein, and left vitelline vein were altered immediately following LAL. Furthermore, we quantified a significant ventral shift of the right common cardinal and right vitelline vein flow streams. We developed an in silico model of LAL, which revealed that wall shear stress was reduced at the left atrioventricular canal and left side of the common ventricle. Conclusions: Our results demonstrate that intracardiac flow patterns change immediately following LAL, supporting the role of hemodynamics in the progression of HLHS. Sites of reduced WSS revealed by computational modeling are commonly affected in HLHS, suggesting that changes in the biomechanical environment may lead to abnormal growth and remodeling of left heart structures. Developmental Dynamics 243:652–662, 2014. © 2013 Wiley Periodicals, Inc.
Effects of reproductive condition, roost microclimate, and weather patterns on summer torpor use by a vespertilionid bat
Authors: Johnson Joseph S. , Lacki Michael J.
Published: December 2013

A growing number of mammal species are recognized as heterothermic, capable of maintaining a high‐core body temperature or entering a state of metabolic suppression known as torpor. Small mammals can achieve large energetic savings when torpid, but they are also subject to ecological costs. Studying torpor use in an ecological and physiological context can help elucidate relative costs and benefits of torpor to different groups within a population. We measured skin temperatures of 46 adult Rafinesque's big‐eared bats (Corynorhinus rafinesquii) to evaluate thermoregulatory strategies of a heterothermic small mammal during the reproductive season. We compared daily average and minimum skin temperatures as well as the frequency, duration, and depth of torpor bouts of sex and reproductive classes of bats inhabiting day‐roosts with different thermal characteristics. We evaluated roosts with microclimates colder (caves) and warmer (buildings) than ambient air temperatures, as well as roosts with intermediate conditions (trees and rock crevices). Using Akaike's information criterion (AIC), we found that different statistical models best predicted various characteristics of torpor bouts. While the type of day‐roost best predicted the average number of torpor bouts that bats used each day, current weather variables best predicted daily average and minimum skin temperatures of bats, and reproductive condition best predicted average torpor bout depth and the average amount of time spent torpid each day by bats. Finding that different models best explain varying aspects of heterothermy illustrates the importance of torpor to both reproductive and nonreproductive small mammals and emphasizes the multifaceted nature of heterothermy and the need to collect data on numerous heterothermic response variables within an ecophysiological context.
Coprecipitation of Oxalates: An Easy and Reproducible Wet‐Chemistry Synthesis Route for Transition‐Metal Ferrites
Authors: Diodati Stefano , Nodari Luca , Natile Marta Maria , Caneschi Andrea , de Julián Fernández César , Hoffmann Claudia , Kaskel Stefan , Lieb Alexandra , Di Noto Vito , Mascotto Simone , Saini Roberta , Gross Silvia
Published: December 2013

In this work, an easy, quick and reproducible wet‐synthesis coprecipitation route starting from oxalate precursors was optimised to synthesise cobalt, nickel, zinc and magnesium spinel ferrites CoFe2O4, NiFe2O4, ZnFe2O4 and MgFe2O4, as well as the manganese perovskite ferrite MnFeO3. Crystalline purity and crystallite sizes ranging from 30 to 190 nm were investigated by means of powder X‐ray diffraction, and uniform morphology of the particles was shown through transmission electron microscopy. The chosen synthetic route afforded an excellent stoichiometric control over the products, as confirmed by combined X‐ray photoelectron spectroscopy and inductively coupled plasma atomic emission spectroscopy analyses. The site geometry, degree of inversion in the spinels and chemical environments in the ferrites were explored by Mössbauer spectroscopy. The thermal evolution of the compounds during calcination and the decomposition pattern of the oxalates were studied through differential scanning calorimetry coupled with thermogravimetric analysis as well as in situ temperature‐programmed X‐ray diffraction. Magnetic properties of these oxides, as well as the transition of the perovskite from paramagnetic to ferrimagnetic behaviour at low temperatures, were investigated by superconducting quantum interferometer magnetometry.
The Effect of Pressure on the Cooperative Spin Transition in the 2D Coordination Polymer {Fe(phpy)2[Ni(CN)4]}
Authors: Gaspar Ana B. , Levchenko Georgiy , Terekhov Sergey , Bukin Gennadiy , Valverde‐Muñoz Javier , Muñoz‐Lara Francisco J. , Seredyuk Maksym , Real José A.
Published: December 2013

The effect of pressure on the spin‐transition properties of the 2D coordination polymer {Fe(phpy)2[Ni(CN)4]} is reported. The study has been carried out by means of variable‐temperature (10–310 K) magnetic susceptibility measurements at applied pressures of 105 Pa to 1.0 GPa and spectroscopic studies in the visible region at room temperature (105 Pa–3.0 GPa). As the pressure is increased, the characteristic temperature of the spin transition is displaced to higher temperatures and the thermal hysteresis loop disappears. A cooperative first‐order spin transition characterized by a piezo‐hysteresis loop about 0.3 GPa wide was observed at 293 K.
A Metal‐Free Route to CF3‐Containing Oxindoles by PhI(OAc)2‐Mediated Trifluoromethylation of N‐Arylacrylamides with TMSCF3
Authors: Fu Weijun , Xu Fengjuan , Fu Yuqin , Xu Chen , Li Shihui , Zou Dapeng
Published: December 2013

A mild and efficient PhI(OAc)2‐mediated trifluoromethylation reaction of N‐arylacrylamides with TMSCF3 under metal‐free conditions was developed. This method provides convenient access to a variety of useful CF3‐containing oxindoles in moderate to good yields.
Stereoselective Construction of 2,8‐Dioxabicyclo[3.3.1]nonane/nonene Systems from 3‐C‐Branched Glycals
Authors: Reddy Gadi Madhusudhan , Sridhar Perali Ramu
Published: December 2013

A stereoselective approach for the formation of 2,8‐dioxabicyclo[3.3.1]nonane/nonene frameworks through the formation of 3‐C‐branched glycals encompassing the Claisen rearrangement of the carbohydrate‐derived allyl‐vinyl ethers and TMSOTf‐catalyzed acetalization reactions as key steps is revealed. A novel acetalization of 3‐C‐branched glycals with a tentative mechanism is proposed. The expedient protocol is evaluated by synthesizing a number of 2,8‐dioxabicyclo[3.3.1]nonane/nonene architectures.