bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Porous Covalent Quinazoline Networks (CQNs) and Their Gas Sorption Properties
Authors: Buyukcakir Onur , Yuksel Recep , Jiang Yi , Lee Sun Hwa , Seong Won Kyung , Chen Xiong , Ruoff Rodney S. 
Published: November 2018

AbstractThe development of different classes of porous polymers by linking organic molecules using new chemistries still remains a great challenge. Herein, we introduce for the first time the synthesis of covalent quinazoline networks (CQNs) using an ionothermal synthesis protocol. Zinc chloride (ZnCl2) was used as the solvent and catalyst for the condensation of aromatic ortho‐aminonitriles to produce tricycloquinazoline linkages. The resulting CQNs show a high porosity with a surface area up to 1870 m2 g−1. Varying the temperature and the amount of catalyst enables us to control the surface area as well as the pore size distribution of the CQNs. Furthermore, their high nitrogen content and significant microporosity make them a promising CO2 adsorbent with a CO2 uptake capacity of 7.16 mmol g−1 (31.5 wt %) at 273 K and 1 bar. Because of their exceptional CO2 sorption properties, they are promising candidates as an adsorbent for the selective capture of CO2 from flue gas.
Threonine stabilizer‐controlled well‐dispersed small palladium nanoparticles on modified magnetic nanocatalyst for Heck cross‐coupling process in water
Authors: Sarvi Iraj , Gholizadeh Mostafa , Izadyar Mohammad 
Published: November 2018

We report the synthesis of magnetically separable Fe3O4@Silica‐Threonine‐Pd0 magnetic nanoparticles with a core–shell structure. After synthesis of Fe3O4@Silica, threonine as an efficient stabilizer/ligand was bonded to the surface of Fe3O4@Silica. Then, palladium nanoparticles were generated on the threonine‐modified catalyst. The threonine stabilizer helps to generate palladium nanoparticles of small size (less than 4 nm) with high dispersity and uniformity. Magnetically separable Fe3O4@Silica‐Threonine‐Pd0 nanocatalyst was fully characterized using various techniques. This nanocatalyst efficiently catalysed the Heck cross‐coupling reaction of a variety of substrates in water medium as a green, safe and inexpensive solvent at 80°C. The Fe3O4@Silica‐Threonine‐Pd0 catalyst was used for at least eight successful consecutive runs with palladium leaching of only 0.05%.
A new air‐stable and reusable tetraphosphine ligand for rhodium‐catalyzed hydroformylation of terminal olefins at low temperature
Authors: Zhou Fanding , Zhang Lin , Wu Qianhui , Guo Fuya , Tang Songbai , Xu Bin , Yuan Maolin , Fu Haiyan , Li Ruixiang , Zheng Xueli , Chen Hua 
Published: November 2018

Tetraphosphine and bisphosphine ligands were synthesized, characterized and employed in Rh‐catalyzed hydroformylation of 1‐octene and 1‐hexene. Conversion of over 97.7% and aldehyde yield of 94.1% were achieved at 60°C, 20 bar. This remarkable performance could also be retained at lower temperature (i.e. 40°C) by prolonging the reaction time. The tetraphosphine ligand‐modified Rh catalyst could be reused for at least seven successive runs with catalytic activity and selectivity almost unchanged; the catalyst was separated from the products and recycled directly in homogeneous hydroformylation, indicating that the catalyst might have good stability. 31P NMR and high‐resolution mass spectral characterization hinted that the reason for the reusability of the catalyst might be that the tetraphosphine ligand is relatively air‐stable and is probably slowly oxidized during the recycling runs. The tetraphosphine ligand has four phosphorus atoms to be partially oxidized and could still coordinate with the Rh center via the unoxidized phosphorus atoms to stabilize the catalyst, based on the multiple chelating modes of the tetraphosphine ligand. Hence, the catalytic activity and selectivity could be retained for a certain number of runs.
Isophorone‐boronate ester: A simple chemosensor for optical detection of fluoride anion
Authors: Ranjith Kumar Jakku , Rami Reddy Eda , Trivedi Rajiv , Vardhaman Anil Kumar , Giribabu Lingamallu , Mirzadeh Nedaossadat , Bhargava Suresh K. 
Published: November 2018

A highly selective isophorone‐boronate ester based chemosensor, (1), having a dicyanovinyl moiety as a convenient colorimetric probe, has been designed. Different types of anionic analyte such as CH3COO−, ClO4−, Cl−, F−, PF6−, Br− and HSO4− were tested and among them only highly nucleophilic F− anion displayed significant response towards the sensor. Addition of the fluoride anion across the boron atom disrupts the π‐conjugation thereby shifts the absorption wavelength towards the redshift region due to the decrease in the HOMO‐LUMO energy gap and a colour change from yellow to blue is observed under visible light condition. The detection limit of this probe was calculated to be 3.25 × 10—8 M for fluoride anion. The binding constants and the detection limits of the sensor were calculated using absorption titration studies. The silica gel TLC strips dip‐coated by the chemosensor (1) revealed a colour change from yellow to brick red to naked eye.
Synthesis and Structures of Arene Ruthenium (II)–NHC Complexes: Efficient Catalytic α‐alkylation of ketones via Hydrogen Auto Transfer Reaction
Authors: Balamurugan Gunasekaran , Balaji Sundarraman , Ramesh Rengan , Bhuvanesh Nattamai S.P. 
Published: November 2018

A panel of six new arene Ru (II)‐NHC complexes 2a‐f, (NHC = 1,3‐diethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1a, 1,3‐dicyclohexylmethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1b and 1,3‐dibenzyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1c) were synthesized from the transmetallation reaction of Ag‐NHC with [(η6‐arene)RuCl2]2 and characterized. The ruthenium (II)‐NHC complexes 2a‐f were developed as effective catalysts for α‐alkylation of ketones and synthesis of bioactive quinoline using primary/amino alcohols as coupling partners respectively. The reactions were performed with 0.5 mol% catalyst load in 8 h under aerobic condition and the maximum yield was up to 96%. Besides, the different alkyl wingtips on NHC and arene moieties were studied to differentiate the catalytic robustness of the complexes in the transformations.
First Report about Mineral Content, Fatty Acids Composition and Biological Activities of Four Wild Edible Mushrooms
Authors: Dimitrijevic Marija V. , Mitic Violeta D. , Nikolic Jelena S. , Djordjevic Aleksandra S. , Mutic Jelena J. , Stankov Jovanovic Vesna P. , Stojanovic Gordana S. 
Published: November 2018

AbstractThe goal of this research was a comprehensive analysis of four wild edible mushroom species, Cantharellus cinereus, Clavariadelphus pistillaris, Clitocybe nebularis and Hygrocybe punicea, which have not been analyzed so far. Extracts of different polarities have been prepared and evaluated for their antioxidant activities by DPPH, ABTS, FRAP, TRP and CUPRAC methods. For all extracts, total phenolic content was determined. Based on the analysis, it was shown that solvent type had a significant effect on the antioxidant capacities of mushroom extracts, so water extracts showed the highest activity. Furthermore, the analysis includes determination of mineral composition, fatty acid profiles and antimicrobial activity. Unsaturated fatty acids, which are very important for human health, are dominant in the studied mushroom species. Linoleic and oleic acid consist of over 50 % of the total fatty acid composition. Seventeen biologically important and toxic elements have been analyzed by ICP‐OES and ICP‐MS and results showed that the element concentrations were species‐dependent. Also, it has been found that analyzed mushrooms did not show any antimicrobial activity. Chemometric analysis was used to understand the connection between the extracts of different polarities.
Development of Sulfonic‐Acid‐Functionalized Mesoporous Materials: Synthesis and Catalytic Applications
Authors: Doustkhah Esmail , Lin Jianjian , Rostamnia Sadegh , Len Christophe , Luque Rafael , Luo Xiliang , Bando Yoshio , Wu Kevin C.‐W. , Kim Jeonghun , Yamauchi Yusuke , Ide Yusuke 
Published: November 2018

AbstractSulfonic acid based mesostructures (SAMs) have been developed in recent years and have important catalytic applications. The primary applications of these materials are in various organic synthesis reactions, such as multicomponent reactions, carbon–carbon bond couplings, protection reactions, and Fries and Beckman rearrangements. This review aims to provide an overview of the recent developments in the field of SAMs with a particular emphasis on the reaction scope and advantages of heterogeneous solid acid catalysts.
Polar‐Group Activated Isospecific Coordination Polymerization of ortho‐Methoxystyrene: Effects of Central Metals and Ligands
Authors: Chai Yunjie , Wang Lingfang , Liu Dongtao , Wang Zichuan , Run Mingtao , Cui Dongmei 
Published: November 2018

AbstractStereoselective polymerization of polar vinyl monomers has been a long‐standing challenge because the employed transition‐metal catalysts are easily poisoned by polar groups of monomers. In this contribution, a series of β‐diketiminato rare‐earth metal complexes 1–5 (L1–5Ln(CH2SiMe3)2(THF)n, Ln=Gd–Lu, Y, and Sc) were successfully synthesized. In combination with AliBu3 and [Ph3C][B(C6F5)4], complexes 1 c(Tb)–1 g(Tm) exhibited high activities and excellent isoselectivities for the polymerization of ortho‐methoxystyrene (oMOS), in which, the polar methoxy group of oMOS did not poison but activated the polymerization through σ–π chelation to the active species together with the vinyl group. Moreover, the large Gd‐attached precursor 1 b showed a higher activity, albeit with a slightly decreased isoselectivity. The small Sc‐attached precursor 1 i was completely inert. Meanwhile, the spatial steric arrangement and the coordination mode of the β‐diketiminato ligand could clearly affect and even block oMOS polymerization. This work sheds new light on the coordination polymerization of polar monomers.
Diverse Reactivity of Dienes with Pentaphenylborole and 1‐Phenyl‐2,3,4,5‐Tetramethylborole Dimer
Authors: Baker J. J. , Al Furaiji Khadilah H. M. , Liyanage O. Tara , Wilson David J. D. , Dutton Jason L. , Martin Caleb D. 
Published: November 2018

AbstractThe reactions of a monomeric borole and a dimeric borole with 2,3‐dimethyl‐1,3‐butadiene and 1,3‐cyclohexadiene were investigated. The monomeric borole reacted at ambient temperature whereas heat was required to crack the dimer to form the monomer and induce reactivity. 2,3‐Dimethyl‐1,3‐butadiene reacts to give diverse products resulting from a cycloaddition process with the B−C moiety of the boroles acting as a dienophile, followed by rearrangements to furnish bicyclic species. For 1,3‐cyclohexadiene, a [4+2] process is observed in which 1,3‐cyclohexadiene serves as the dienophile and the boroles as the diene partner. The experimental results are corroborated with mechanistic theoretical calculations that indicate boroles can serve as either a diene or dienophile in cycloaddition reactions with dienes.
Adsorption of Cyclohexane in Pure Silica Zeolites: High‐Throughput Computational Screening Validated by Experimental Data
Authors: Sławek Andrzej , Grzybowska Karolina , Vicent‐Luna José Manuel , Makowski Wacław , Calero Sofía 
Published: November 2018

AbstractAdsorption of cyclohexane in pure silica zeolites was studied experimentally and by molecular simulations. Based on the adsorption isobars obtained from the quasi‐equilibrated temperature adsorption and desorption (QE‐TPDA) measurements and reported adsorption isotherms for high‐silica zeolites Y, ZSM‐5, and ZSM‐11 we refined Lennard‐Jones parameters for guest‐host interactions available in the literature. Adsorption of cyclohexane from equimolar mixture of twisted‐boat and chair conformations has been screened in 171 pure silica zeolitic structures using grand canonical Monte Carlo simulations. Almost 20 frameworks showing extraordinary preference for adsorption of the chair conformation over the twisted boat one or vice versa were found. This selectivity was attributed to the geometry of channels and cavities present in the pore structures, as all t‐boat selective structures possess channels or cavities of 8.3–9.1 Å. We also differentiated ways of chair‐selectivity depending on the size and shape of the channels or cavities and also on the arrangement of the guest molecules in the pores.
Synthesis, Crystal Growth, and Optical Characterization of a Novel Nonlinear Optical Organic Material: N,N‐Diarylbenzamide
Authors: Lakshmi Radhakrishnan , Prabukanthan Peethambaram , Harichandran Gurusamy , Sudarsana Kumar C. 
Published: November 2018

AbstractNonlinear optical organic materials of N,N‐diphenylbenzamide (NNDPB) and 4‐fluoro‐N,N‐diphenylbenzamide (FNNDPB) are synthesized from benzoylation of N,N‐diphenylamine using the substituted benzoyl chlorides. The single crystals of NNDPB and FNNDPB are grown by a slow evaporation technique. Single‐crystal X‐ray diffraction shows that both the crystals belong to orthorhombic crystallographic system with space group Pbca. Fourier transform infrared spectrum shows the chemical bonding and various functional groups, the carbonyl peak appeared at 1647 and 1651 cm−1 in NNDPB and FNNDPB compounds, respectively. 1H and 13C nuclear magnetic resonance analysis examines the placement of aromatic protons and carbons are identified to the synthesized materials. UV–vis near IR spectra analysis showed 100% transmission in the visible region for both NNDPB and FNNDPB crystals. As‐grown crystal dielectric constant and dielectric loss are inversely proportional to the frequency at all the temperatures. The thermal properties of NNDPB and FNNDPB crystals are studied from thermogravimetric analysis/differential thermal analysis analysis, it is thermally stable up to 483 and 503 K. Crystal growth mechanism and defects are observed from etching studies. The relative second harmonic generation efficiency is measured by Kurtz–Perry powder technique and is found to be 1.55 and 1.7 times as that of potassium dihydrogen phosphate.
Microsponge: An emerging drug delivery strategy
Authors: Singhvi Gautam , Manchanda Prachi , Hans Neha , Dubey Sunil K. , Gupta Gaurav 
Published: November 2018

AbstractMicrosponges are the spherical particles ranging from 5 to 300 μm in size. These are further made up of clusters of smaller spheres. They are designed for delivering the drug efficiently at a comparatively lesser dose and enhancing the stability, modifying the drug release profile and minimizing the side effects. Microsponge drug delivery system decrease transdermal invasion of the active ingredient into the skin while increasing the time the drug remains on the skin surface or within the epidermis. Preparation of the microsponges includes two techniques: Liquid–liquid suspension polymerization and Quasi‐emulsion solvent diffusion method. Their characterization and evaluation can be done in many ways like particle‐size measurement and porosity, morphology, true density determination, analyzing the rheological properties, and dissolution studies. Present work focuses on the detailed study of the microsponge drug delivery system. This will help the reader to get all the information regarding the microsponge delivery systems.
Numerical response of mammalian carnivores to rodents affects bird reproduction in temperate forests: A case of apparent competition?
Authors: Grendelmeier Alex , Arlettaz Raphaël , Pasinelli Gilberto 
Published: November 2018

AbstractResource pulses such as mast seeding in temperate forests may affect interspecific interactions over multiple trophic levels and link different seed and nonseed consumers directly via predation or indirectly via shared predators. However, the nature and strength of interactions among species remain unknown for most resource pulse–driven ecosystems. We considered five hypotheses concerning the influence of resource pulses on the interactions between rodents, predators, and bird reproduction with data from northern Switzerland collected between 2010 and 2015. In high‐rodent‐abundance‐years (HRAYs), wood warbler (Phylloscopus sibilatrix) nest survival was lower than in low‐rodent‐abundance‐years, but rodents were not important nest predators, in contrast to rodent‐hunting predators. The higher proportion of nests predated by rodent‐hunting predators and their increased occurrence in HRAYs suggests a rodent‐mediated aggregative numerical response of rodent‐hunting predators, which incidentally prey on the wood warbler's ground nests. There was no evidence that rodent‐hunting predators responded behaviorally by switching prey. Lastly, nest losses caused by nonrodent‐hunting predators were not related to rodent abundance. We show that wood warblers and rodents are linked via shared predators in a manner consistent with apparent competition, where an increase of one species coincides with the decrease of another species mediated by shared predators. Mast seeding frequency and annual seed production appear to have increased over the past century, which may result in more frequent HRAYs and generally higher peaking rodent populations. The associated increase in the magnitude of apparent competition may thus at least to some extent explain the wood warbler's decline in much of Western Europe.
Improved electrocompetence and metabolic engineering of Clostridium pasteurianum reveals a new regulation pattern of glycerol fermentation
Authors: Schmitz Rebekka , Sabra Wael , Arbter Philipp , Hong Yaeseong , Utesch Tyll , Zeng An‐Ping 
Published: November 2018

AbstractClostridium pasteurianum produces industrially valuable chemicals such as n‐butanol and 1,3‐propanediol from fermentations of glycerol and glucose. Metabolic engineering for increased yields of selective compounds is not well established in this microorganism. In order to study carbon fluxes and to selectively increase butanol yields, we integrated the latest advances in genome editing to obtain an electrocompetent Clostridium pasteurianum strain for further engineering. Deletion of the glycerol dehydratase large subunit (dhaB) using an adapted S. pyogenes Type II CRISPR/Cas9 nickase system resulted in a 1,3‐propanediol‐deficient mutant producing butanol as the main product. Surprisingly, the mutant was able to grow on glycerol as the sole carbon source. In spite of reduced growth, butanol yields were highly increased. Metabolic flux analysis revealed an important role of the newly identified electron bifurcation pathway for crotonyl‐CoA to butyryl‐CoA conversion in the regulation of redox balance. Compared to the parental strain, the electron bifurcation pathway flux of the dhaB mutant increased from 8 to 46% of the overall flux from crotonyl‐CoA to butyryl‐CoA and butanol, indicating a new, 1,3‐propanediol‐independent pattern of glycerol fermentation in Clostridium pasteurianum.
PPARβ/δ‐agonist GW0742 ameliorates dysfunction in fatty acid oxidation in PSEN1ΔE9 astrocytes
Authors: Konttinen Henna , Gureviciene Irina , Oksanen Minna , Grubman Alexandra , Loppi Sanna , Huuskonen Mikko T. , Korhonen Paula , Lampinen Riikka , Keuters Meike , Belaya Irina , Tanila Heikki , Kanninen Katja M. , Goldsteins Gundars , Landreth Gary , Koistinaho Jari , Malm Tarja 
Published: November 2018

AbstractAstrocytes are the gatekeepers of neuronal energy supply. In neurodegenerative diseases, bioenergetics demand increases and becomes reliant upon fatty acid oxidation as a source of energy. Defective fatty acid oxidation and mitochondrial dysfunctions correlate with hippocampal neurodegeneration and memory deficits in Alzheimer's disease (AD), but it is unclear whether energy metabolism can be targeted to prevent or treat the disease. Here we show for the first time an impairment in fatty acid oxidation in human astrocytes derived from induced pluripotent stem cells of AD patients. The impairment was corrected by treatment with a synthetic peroxisome proliferator activated receptor delta (PPARβ/δ) agonist GW0742 which acts to regulate an array of genes governing cellular metabolism. GW0742 enhanced the expression of CPT1a, the gene encoding for a rate‐limiting enzyme of fatty acid oxidation. Similarly, treatment of a mouse model of AD, the APP/PS1‐mice, with GW0742 increased the expression of Cpt1a and concomitantly reversed memory deficits in a fear conditioning test. Although the GW0742‐treated mice did not show altered astrocytic glial fibrillary acidic protein‐immunoreactivity or reduction in amyloid beta (Aβ) load, GW0742 treatment increased hippocampal neurogenesis and enhanced neuronal differentiation of neuronal progenitor cells. Furthermore, GW0742 prevented Aβ‐induced impairment of long‐term potentiation in hippocampal slices. Collectively, these data suggest that PPARβ/δ‐agonism alleviates AD related deficits through increasing fatty acid oxidation in astrocytes and improves cognition in a transgenic mouse model of AD.
Condensations based on 5‐(indol‐3‐yl)‐pyrrolidin‐2‐thiones
Authors: Sadovoy Andrey V. , Kattsyna Veronica V. , Protopopova Polina S. , Nelyubina Yulia V. , Pavlov Alexander A. , Kochetkov Konstantin A. , Sviridova Lyudmila A. 
Published: November 2018

AbstractNew activated indolylpyrrolidones—their methylthiopyrrolinium salts—in the reactions with several CH‐acids were studied. 2‐Nitromethylene‐ and 2‐dicyanomethyleneindolylpyrrolidines were obtained from 5‐indolyl‐2‐methylthiopyrrolinium salts with good yields. The reduction in these nitro compounds yields the respective aminomethylpyrolidines. The rigid structure of the starting compounds has significant stereoelectronic requirements of nucleophilic agents.
Cortactin expression: Association with disease progression and survival in oral squamous cell carcinoma
Authors: Horn Dominik , Gross Madeleine , Dyckhoff Gerhard , Fuchs Jennifer , Grabe Niels , Weichert Wilko , Herpel Esther , Herold‐Mende Christel , Lichter Peter , Hoffmann Jürgen , Hess Jochen , Freier Kolja 
Published: November 2018

AbstractBackgroundCortactin (CTTN) is located on chromosome 11q13 and is associated with invasiveness in various cancer entities. CTTN protein expression could be a prognosticator of oral squamous cell carcinoma (OSCC) in terms of recurrence and survival.MethodsCTTN‐dependent invasion was performed using migration assay in human papillomavirus‐negative head and neck squamous cell carcinoma (HNSCC) cells. Cortactin protein analysis in tissue microarrays was used for correlation with clinical parameters, as well as for survival analysis. Gene expression profiling in HNSCC cells was performed to unreveal CTTN signaling.ResultsKnockdown of CTTN in HNSCC cells showed less invasion in vitro. Gene expression profiling showed various deregulated genes known to be involved in progression. We confirmed the link between CTTN overexpression and progression in a large clinical cohort. High expression was associated with worse overall and progression‐free survival.ConclusionsWe propose CTTN for managing OSCC in terms of adjuvant therapy and aftercare. Furthermore, our study reveals new potential targets in CTTN signaling for individualized OSCC therapy.