bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Fluorinated NH‐Iminophosphonates and Iminocarboxylates: Novel Synthons for the Preparation of Biorelevant α‐Aminophosphonates and Carboxylates.
Authors: Rassukana Yuliya V. , Yelenich Ivanna P. , Synytsya Anatoly D. , Onys'ko Petro P.
Published: September 2014

Previously unknown N—H α‐imino(fluoromethyl)phosphonates and ‐carboxylates (I) are synthesized and functionalized by reactions with O‐, S‐, N‐ and P‐nucleophiles to furnish biorelevant fluorinated aminophosphonates and ‐carboxylates.
ChemInform Abstract: Biorational Synthesis of Iridomyrmecin Diastereomers from Catnip Oil.
Authors: Chauhan Kamlesh R. , Schmidt Walter
Published: September 2014

Four diastereomers of the insecticide iridomyrmecin are prepared in five steps from naturally occurring nepetalactones, which are isolated from catnip oil.
ChemInform Abstract: New Nitrogenous Bisabolene‐Type Sesquiterpenes from a Formosan Sponge Axinyssa sp.
Authors: Liu Wangta , Liang Kai‐Ju , Chiang Ching‐Ying , Lu Mei‐Chin , Su Jui‐Hsin
Published: September 2014

Five nitrogenous bisabolene‐type sesquiterpenes including the two new compounds axinysalines A (I) and B (II) are isolated from a Formosan sponge Axinyssa sp.
ChemInform Abstract: Sanguinamide B Analogues: Identification of Active Macrocyclic Structures.
Authors: Wahyudi Hendra , Tantisantisom Worawan , McAlpine Shelli R.
Published: September 2014

Several analogues of sanguinamide B (Ia) are synthesized and their inhibition activity against cell proliferation HCT‐116 drug resistant colon cancer cell lines are tested.
ChemInform Abstract: C—N Bond Formation via Cu‐Catalyzed Cross‐Coupling with Boronic Acids Leading to Methyl Carbazole‐3‐carboxylate: Synthesis of Carbazole Alkaloids.
Authors: Rasheed Sk. , Rao D. Nageswar , Reddy K. Ranjith , Aravinda S. , Vishwakarma Ram A. , Das Parthasarathi
Published: September 2014

Copper catalyzed N‐arylation of iodoarenes with boronic acids followed by palladium catalyzed intramolecular C‐H arylation provides carbazole‐3‐carboxylates including the naturally occurring alkaloids Clausine C (IVg), H (IVf) and L (IVe).
ChemInform Abstract: Further Biphenyl Lignans with a Tetrahydrofuran Moiety from Gymnotheca chinensis
Authors: Xiao Shiji , He Dahai , Fang Dongmei , Chen Fang , Ding Lisheng , Zhou Yan
Published: September 2014

isolation and structure elucidation of four new atropisomeric biphenyl lignans, gymnothelignans P—S
ChemInform Abstract: Antiinflammatory Components of Euphorbia humifusa Willd.
Authors: Luyen Bui Thi Thuy , Tai Bui Huu , Thao Nguyen Phuong , Eun Kim Ji , Cha Ji Yun , Xin Ming Jie , Lee Young Mi , Kim Young Ho
Published: September 2014

Two new compounds, euphorbinoside (I) and dehydropicrorhiza acid methyl ester (II), are isolated from Euphorbia humifusa along with 24 known compounds.
ChemInform Abstract: Challenges in Reduction of Dinitrogen by Proton and Electron Transfer
Authors: van der Ham Cornelis J. M. , Koper Marc T. M. , Hetterscheid Dennis G. H.
Published: September 2014

Review: reaction mechanisms of a dissociative, an alternating associative, and a distal associative pathway, 50 refs.
ChemInform Abstract: Superconductivity and Ferromagnetic Quantum Criticality in Uranium Compounds
Authors: Aoki Dai , Flouquet Jacques
Published: September 2014

Review: 46 refs.
ChemInform Abstract: Design and Development of Ligands for Palladium‐Catalyzed Carbonylation Reactions
Authors: Fang Weiwei , Zhu Haibo , Deng Qinyue , Liu Shuangliang , Liu Xiyu , Shen Yajing , Tu Tao
Published: September 2014

Review: [135 refs.
ChemInform Abstract: Thiazolothiadiazoles and Thiazolooxadiazoles: Synthesis and Biological Applications
Authors: Abdel‐Wahab Bakr F. , Shaaban Saad
Published: September 2014

Review: [53 refs.
ChemInform Abstract: Reactions of Metallocarbenes Derived from N‐Sulfonyl‐1,2,3‐triazoles
Authors: Davies Huw M. L. , Alford Joshua S.
Published: September 2014

Review: such as transannulation reactions to generate new heterocycles, cyclopropanation and subsequent ring expansions, ylide formation with subsequent rearrangements, and C—H functionalization; 55 refs.
ChemInform Abstract: Gold‐Catalyzed C(sp3)—H Bond Functionalization
Authors: Xie Jin , Pan Changduo , Abdukader Ablimit , Zhu Chengjian
Published: September 2014

Review: 49 refs.
ChemInform Abstract: Direct Allylation of Alcohols Using Allyltrimethylsilane and a Move Towards an Economical and Ecological Protocol for C—C Bond Formation
Authors: Chaskar Atul , Murugan Kaliyappan
Published: September 2014

Review: 90 refs.
ChemInform Abstract: Reactivity of Carbonyl and Phosphoryl Groups at Calixarenes
Authors: Cacciapaglia Roberta , Di Stefano Stefano , Mandolini Luigi , Salvio Riccardo
Published: September 2014

Review: 48 refs.
ChemInform Abstract: Glycosylated Metal Phthalocyanines
Authors: Hanack Michael , Crucius Goran , Calvete Mario J. F. , Ziegler Thomas
Published: September 2014

Review: methods for the synthesis
ChemInform Abstract: Highly Selective Perfluoroalkylation of Unsaturated Molecules Upon Photoirradiation in BTF as an Organic/Fluorous Hybrid Solvent
Authors: Tamai Taichi , Sonoda Motohiro , Ogawa Akiya
Published: September 2014

Review: 74 refs.
ChemInform Abstract: Dirhodium Caprolactamate and tert‐Butyl Hydroperoxide — A Universal System for Selective Oxidations
Authors: Ratnikov Maxim O. , Doyle Michael P.
Published: September 2014

Review: 119 refs.
ChemInform Abstract: Recent Advances in the Synthesis of Nitroolefin Compounds
Authors: Yan Guobing , Borah Arun Jyoti , Wang Lianggui
Published: September 2014

Review: [51 refs.
ChemInform Abstract: Retrospective View on Recent Developments in Cyclobutane Synthesis via [2 + 2] Photocycloaddition of Unsaturated Ketones to Acyclic Dienes
Authors: Margaretha Paul
Published: September 2014

Review: 24 refs.
ChemInform Abstract: Paal‐Knorr Reaction in the Synthesis of Heterocyclic Compounds
Authors: Khaghaninejad Soheila , Heravi Majid M.
Published: September 2014

Review: 215 refs.
ChemInform Abstract: Fundamental Pd0/PdII Redox Steps in Cross‐Coupling Reactions: Homogeneous, Hybrid Homogeneous‐Heterogeneous to Heterogeneous Mechanistic Pathways for C—C Couplings
Authors: Fairlamb Ian J. S. , Lee Adam F.
Published: September 2014

Review: 114 refs.
ChemInform Abstract: High Birefringence Liquid Crystals
Authors: Dabrowski Roman , Kula Przemyslaw , Herman Jakub
Published: September 2014

Review: 133 refs.
ChemInform Abstract: Computational Studies of Lewis Acidity and Basicity in Frustrated Lewis Pairs
Authors: Gilbert Thomas M.
Published: September 2014

Review: 42 refs.
ChemInform Abstract: Nanocast Mesoporous Mixed Metal Oxides for Catalytic Applications
Authors: Nair Mahesh Muraleedharan , Yen Hoang , Kleitz Freddy
Published: September 2014

Review: 113 refs.
ChemInform Abstract: Fast‐Growing Field of Magnetically Recyclable Nanocatalysts
Authors: Wang Dong , Astruc Didier
Published: September 2014

Review: 457 refs.
ChemInform Abstract: Soil Water Repellency: Dynamics of Heterogeneous Surfaces
Authors: Diehl Doerte
Published: September 2014

Review: 152 refs.
ChemInform Abstract: Design and Synthesis of Organic—Inorganic Hybrid Capsules for Biotechnological Applications
Authors: Shi Jiafu , Jiang Yanjun , Wang Xiaoli , Wu Hong , Yang Dong , Pan Fusheng , Su Yanlei , Jiang Zhongyi
Published: September 2014

Review: 50 refs.
ChemInform Abstract: Semiconductor Heterojunction Photocatalysts: Design, Construction, and Photocatalytic Performances
Authors: Wang Huanli , Zhang Lisha , Chen Zhigang , Hu Junqing , Li Shijie , Wang Zhaohui , Liu Jianshe , Wang Xinchen
Published: September 2014

Review: 50 refs.
ChemInform Abstract: Amyloid‐Based Nanosensors and Nanodevices
Authors: Hauser Charlotte A. E. , Maurer‐Stroh Sebastian , Martins Ivo C.
Published: September 2014

Review: latest advances and major challenges in developing amyloids for future applications in nanotechnology and nanomedicine; 196 refs.
ChemInform Abstract: Thiamine Diphosphate — A Natural Iminium Salt. Its Role in Microbiological Processes During Wine Preparation and on the Aroma of Wine
Authors: Mueller Nikolaus
Published: September 2014

Review: 39 refs.
ChemInform Abstract: Density Functional Theory Simulations of Complex Catalytic Materials in Reactive Environments: Beyond the Ideal Surface at Low Coverage
Authors: Chizallet Celine , Raybaud Pascal
Published: September 2014

Review: 195 refs.
ChemInform Abstract: Theory and Simulation of Atom Tunneling in Chemical Reactions
Authors: Kaestner Johannes
Published: September 2014

Review: 82 refs.
ChemInform Abstract: Isotope Effects in ESR Spectroscopy
Authors: Stoesser Reinhard , Herrmann Werner
Published: September 2014

Review: 176 refs.
ChemInform Abstract: Nano‐ and Microstructuration of Supramolecular Materials Driven by H‐Bonded Uracil·2,6‐diamidopyridine Complexes
Authors: Marangoni Tomas , Bonifazi Davide
Published: September 2014

Review: 131 refs.
Dysmyelination with preservation of transverse bands in a long‐lived allele of the quaking mouse
Authors: Chaverneff Florence , Mierzwa Amanda , Weinstock Michael , Ketcham Maren , Lang Eric J. , Rosenbluth Jack
Published: September 2014

The new mutant mouse shaking (shk) differs from other “myelin mutants” in having a more stable neurological impairment and a much longer lifespan. We have shown that transverse bands (TBs), the component of the paranodal junction (PNJ) that attaches the myelin sheath to the axon, are present in the shk central nervous system (CNS), in contrast to more severely affected mutants, in which TBs are absent or rare. We have proposed that TBs are the major determinant underlying shk neurological stability and longevity. Here we report that TBs are abundant not only in the shk CNS but also in its peripheral nervous system (PNS), which, as in other “myelin mutants”, is not as severely dysmyelinated as the CNS but does display structural abnormalities likely to affect impulse propagation. In particular, myelin sheaths are thinner than normal, and some axonal segments lack myelin sheaths entirely. In addition, we establish that the shk mutation, previously localized to chromosome 17, is a quaking (qk) allele consisting of a 105‐nucleotide insertion in the qk regulatory region that decreases qk transcription but does not extend to the Parkin and Parkin coregulated genes, which are affected in the qk allele. We conclude that: 1) dysmyelination is less severe in the shk PNS than in the CNS, but TBs, which are present in both locations, stabilize the PNJs and prevent the progressive neurological deficits seen in mutants lacking TBs; and 2) the insertional mutation in shk mice is sufficient to produce the characteristic neurological phenotype without involvement of the Parkin and Parkin coregulated genes. J. Comp. Neurol. 523:197–208, 2015. © 2014 Wiley Periodicals, Inc.
Identification and distribution of SIFamide in the nervous system of the desert locust Schistocerca gregaria
Authors: Gellerer Alina , Franke Aileen , Neupert Susanne , Predel Reinhard , Zhou Xin , Liu Shanlin , Reiher Wencke , Wegener Christian , Homberg Uwe
Published: September 2014

SIFamides are a family of highly conserved arthropod neuropeptides. To date, nine orthocopies from different arthropods, most of them insects, have been identified, all consisting of 11–12 amino acid residues. The striking conservation in sequence is mirrored by highly similar morphologies of SIFamide‐immunoreactive neurons: immunolabeling in various insect species revealed four immunopositive neurons with somata in the pars intercerebralis and arborizations extending throughout the brain and ventral nervous system. In contrast, the functional role of these neurons and their neuropeptide SIFamide is largely obscure. To provide an additional basis for functional analysis, we identified, by matrix‐assisted laser desorption/ionization time of flight (MALDI–TOF) mass spectrometry, a SIFamide peptide in the desert locust Schistocerca gregaria and studied its distribution throughout the nervous system. Identification was supported by analysis of transcriptomic data obtained from another grasshopper, Stenobothrus lineatus. Scg‐SIFamide, unlike all SIFamides identified so far, is a pentadecapeptide with an extended and highly modified N‐terminus (AAATFRRPPFNGSIFamide). As in other insects, pairs of descending neurons with somata in the pars intercerebralis and ramifications in most areas of the nervous system are SIFamide‐immunoreactive. In addition, a small number of local interneurons in the brain and ventral ganglia were immunostained. Double‐label experiments showed that the SIFamide‐immunoreactive descending neurons are identical to previously characterized primary commissure pioneer (PNP) neurons of the locust brain that pioneer the first commissure in the brain. The data suggest that the descending SIFamide‐immunoreactive neurons play a developmental role in organizing the insect central nervous system. J. Comp. Neurol. 523:108–125, 2015. © 2014 Wiley Periodicals, Inc.
Synthesis and self‐assembled mechanism of CuO peony‐flowers by a composite hydroxide‐mediated approach at low temperature
Authors: Liu Min , Jin Hongyun , Liu Meiying , Dong Jie , Hou Pan , Ji Zhengjia , Hou Shuen
Published: September 2014

A composite‐hydroxide mediated (CHM) method was utilized for the synthesis of CuO peony‐flower nanostructures under temperatures ranging between 25 and 160 °C. The CHM mechanism was confirmed through X‐ray Powder Diffraction (XRD) and a Thermo‐Gravimetric Differential Scanning Calorimeter (TG‐DSC). Cu(NO3)2 was shown to transform into Cu(OH)2 in the mixed alkalis (NaOH/KOH); the reaction was facilitated by the solvent properties of the mixed alkalis. Cu(OH)2 subsequently consumed H2O in the adsorption of the mixed alkalis at 25∼65 °C. At higher reaction temperatures (>65 °C), the Cu(OH)2 was seen to decompose at an accelerated rate. Therefore, crystalline CuO could be obtained not only above 65 °C but also at 25 °C. The crystal morphology and structure of CuO were examined through Filed Emission Scanning Electron Microscopy (FE‐SEM) and Transmission Electron Microscopy (TEM). It was determined that the CuO peony‐flower had a polycrystalline structure composed of single crystalline CuO petals. Using the Selected Area Electron Diffraction (SAED) results, the rings were indexed as (002), (111), (112), (202) and (−113), which was in agreement with the XRD results. With increasing temperature, the CuO flower petals self‐assembled through random aggregation and gathered CuO nanorod parts, which led to incomplete CuO flower petals through orientated aggregation. Prolonged reaction time led to the growth of CuO flower petals in the direction of [001]. An ideal CuO flower structure was observed through TEM observation.
Curcumin Inhibits the Proliferation and Invasiveness of MHCC97‐H Cells via p38 Signaling Pathway
Authors: Zhang Kai , Rui Xiaojiang , Yan Xi
Published: September 2014

Preclinical Research

Curcumin has been reported to be effective as a cancer therapy. However, the anti‐metastatic effect and molecular mechanism(s) of curcumin in hepatocellular carcinoma (HCC) remain poorly understood. The purpose of this study was to test the effects of curcumin on HCC and its putative mechanism(s). Curcumin inhibited the proliferation of HCC cells and inhibited the migration and invasion of these cells at sub‐cytotoxic concentrations. Curcumin also decreased the expression and activity of matrix metalloproteinases (MMP)‐2 and MMP‐9, and reduced p38 phosphorylation. Combination treatment of HCC cells with curcumin and SB203580 (a p38 signaling pathway inhibitor), generated a synergistic effect on the expression of MMP‐2 and MMP‐9, suggesting that the anti‐metastatic effect of curcumin on HCC may involve a p38 signaling pathway.
Opportunities and Challenges Provided by Cloud Repositories for Bioinformatics‐Enabled Drug Discovery
Authors: Dalpé Gratien , Joly Yann
Published: September 2014

Strategy, Management and Health Policy

Enabling Technology, Genomics, Proteomics
Preclinical Research
Postmarketing Phase IV

Healthcare‐related bioinformatics databases are increasingly offering the possibility to maintain, organize, and distribute DNA sequencing data. Different national and international institutions are currently hosting such databases that offer researchers website platforms where they can obtain sequencing data on which they can perform different types of analysis. Until recently, this process remained mostly one‐dimensional, with most analysis concentrated on a limited amount of data. However, newer genome sequencing technology is producing a huge amount of data that current computer facilities are unable to handle. An alternative approach has been to start adopting cloud computing services for combining the information embedded in genomic and model system biology data, patient healthcare records, and clinical trials' data. In this new technological paradigm, researchers use virtual space and computing power from existing commercial or not‐for‐profit cloud service providers to access, store, and analyze data via different application programming interfaces. Cloud services are an alternative to the need of larger data storage; however, they raise different ethical, legal, and social issues. The purpose of this Commentary is to summarize how cloud computing can contribute to bioinformatics‐based drug discovery and to highlight some of the outstanding legal, ethical, and social issues that are inherent in the use of cloud services.
Epigenomic Networking in Drug Development: From Pathogenic Mechanisms to Pharmacogenomics
Authors: Cacabelos Ramón
Published: September 2014

Preclinical Research

Different epigenetic alterations (DNA methylation, histone modifications, chromatin remodeling, noncoding RNA dysregulation) are associated with the phenotypic expression of complex disorders in which genomic, epigenomic, proteomic, and metabolomic changes, in conjunction with environmental factors, are involved. As epigenetic modifications are reversible and can be potentially targeted by pharmacological and dietary interventions, a series of epigenetic drugs have been developed, including DNA methyltransferase inhibitors (nucleoside analogs, small molecules, bioproducts, antisense oligonucleotides, miRNAs), histone deacetylase inhibitors (short‐chain fatty acids, hydroxamic acids, cyclic peptides, benzamides, ketones, sirtuin inhibitors, sirtuin activators), histone acetyltransferase modulators, histone methyltransferase inhibitors, histone demethylase inhibitors, and noncoding RNAs (miRNAs), with potential effects against myelodysplastic syndromes, different types of cancer, and neurodegenerative disorders. Pharmacogenetic and pharmacoepigenetic studies are required for the proper evaluation of efficacy and safety issues in clinical trials with epigenetic drugs.
Correcting Transcription Factor Gene Sets for Copy Number and Promoter Methylation Variations
Authors: Rathi Komal S. , Gaykalova Daria A. , Hennessey Patrick , Califano Joseph A. , Ochs Michael F.
Published: September 2014

Preclinical Research

Gene set analysis provides a method to generate statistical inferences across sets of linked genes, primarily using high‐throughput expression data. Common gene sets include biological pathways, operons, and targets of transcriptional regulators. In higher eukaryotes, especially when dealing with diseases with strong genetic and epigenetic components such as cancer, copy number loss and gene silencing through promoter methylation can eliminate the possibility that a gene is transcribed. This, in turn, can adversely affect the estimation of transcription factor or pathway activity from a set of target genes, as some of the targets may not be responsive to transcriptional regulation. Here we introduce a simple filtering approach that removes genes from consideration if they show copy number loss or promoter methylation, and demonstrate the improvement in inference of transcription factor activity in a simulated dataset based on the background expression observed in normal head and neck tissue.
Genetic Findings in Obsessive–Compulsive Disorder Connect to Brain‐Derived Neurotropic Factor and Mammalian Target of Rapamycin Pathways: Implications for Drug Development
Authors: Grados Marco , Sung Hyung Mo , Kim Sejin , Srivastava Siddharth
Published: September 2014

Preclinical Research

Traditional pharmacological approaches to the treatment of obsessive–compulsive disorder (OCD) are based on affecting serotonergic and dopaminergic transmission in the central nervous system. However, genetic epidemiology findings are pointing to glutamate pathways and developmental genes as etiological in OCD. A review of recent genetic findings in OCD is conducted, and bioinformatics approaches are used to locate pathways relevant to neuroprotection. The OCD susceptibility genes DLGAP1, RYR3, PBX1‐MEIS2, LMX1A and candidate genes BDNF and GRIN2B are components of the neuronal growth, differentiation and neurogenesis pathways BDNF‐mTOR. These pathways are emerging as a promising area of research for the development of neuroprotective pharmaceuticals. Emergent genetic epidemiologic data on OCD and repetitive behaviors may support new approaches for pharmacological discovery. Neuroprotective approaches that take into consideration glutamate‐mediated BDNF‐mTOR pathways are suggested by OCD susceptibility genes.
Microarray Gene and miRNA Expression Studies: Looking for New Therapeutic Targets for Frontotemporal Lobar Degeneration
Authors: Milanesi Elena , Pilotto Andrea
Published: September 2014

Preclinical Research

Frontotemporal lobar degeneration (FTLD) encompasses a spectrum of neurodegenerative disorders characterized by behavioral, executive and language impairment, with a common overlap with parkinsonism and motor‐neuron disease. Despite an increased understanding of its genetic background and molecular pathophysiology, FTLD is still an orphan disorder and there are currently no effective therapies available. In this brief overview we report the results obtained by several high‐throughput and bioinformatic studies aimed at discovering impairment in the transcriptional profiles in brain and peripheral tissues from FTLD patients and in animal models. Taken together, all these results provide an interesting but still fragmentary list of genes and miRNAs whose role in FTLD should be thoroughly investigated.
Advancing Cancer Patient Care by Integrating Circulating Tumor Cell Technology to Understand the Spatial and Temporal Dynamics of Cancer
Authors: Rodriguez‐Lee Mariam , Kuhn Peter , Webb David R.
Published: September 2014

Preclinical Research

Spatial and temporal dynamics of cancer, studied with physical science approaches at critical transition points of the disease can provide insight into the biology of cancer and the evolutionary changes that occur both naturally and in response to therapy. A very promising development in translational cancer medicine has been the emergence of circulating tumor cells (CTC) as minimally invasive “liquid biopsies.” We envision that the future utility of CTC will not simply be confined to enumeration, but also include their routine characterization using a high‐content approach that investigates morphometrics, protein expression and genomic profiling. This novel approach guided by mathematical models to predict the spread of disease from the primary site to secondary site can bring the bench to the bedside for cancer patients. It is agnostic with reference to drug choice and treatment regimen, which also means that each patient is unique. The approach is Bayesian from a data collection perspective and is patient‐centric rather than drug or new chemical entity–centric. The analysis of data comes from an understanding of commonalities and differences that are detected among patients with a given cancer type. Thus, patients are treated over the course of their disease with various drug regimens that reflects our real‐time understanding of their evolving tumor genomics and response to treatment. This likely means that smaller cohorts of patients receive any given regimen but we hypothesize that it would lead to better patient outcomes than with the current classic approach to drug testing and development.
Nickel and Copper Complexes of Pyrrolecarboxamide Ligands – Stabilization of M3+ Species and Isolation of Ni3+ Complexes
Authors: Kumar Sushil , Munjal Megha , Singh Jyoti , Gupta Rajeev
Published: September 2014

We report NiII and CuII complexes of a few pyrrolecarboxamide ligands containing –H, –Cl, and –CH3 substituents on the phenylene ring. Solid‐state X‐ray diffraction and solution‐based spectral studies substantiated a square‐planar geometry around the metal ions in all six of the MII complexes. Electrochemical studies showed that the electronic substituents considerably influence the M3+/2+ redox potentials. All of the complexes exhibit considerably low M3+/2+ redox potentials owing to their tetraanionic coordination environments. Chemical and/or electrochemical oxidation has resulted in the isolation of Ni3+ complexes and the generation of Cu3+ species. The spectroscopic studies revealed square‐planar geometries around the metal ions in the resultant Ni3+ and Cu3+ complexes.
TiO2/Eu3+ Thin Films with High Photoluminescence Emission Prepared by Electrophoretic Deposition from Nanoparticulate Sols
Authors: Borlaf Mario , Colomer María T. , de Andrés Alicia , Cabello Fátima , Serna Rosalia , Moreno Rodrigo
Published: September 2014

The light emission properties of anatase TiO2/Eu3+ thin films prepared by electrophoretic deposition and of the corresponding precursor nanoparticulate sols and xerogels with different Eu3+ contents are reported. Transparent anatase TiO2 thin films were successfully obtained by electrophoretic deposition after dilution of the original sols with ethanol in order to inhibit the water hydrolysis and facilitate the drying process. The topography of the films shows a high homogeneous distribution in terms of grain size and roughness of the surface of the thin films. The film thickness varied from 50 nm to 800 nm and it was found to be strongly dependent on the Eu3+ content of the sols, probably because of uncompensated electrical charges provided by Eu3+ ions located at the surface of the nanoparticles. A spontaneous densification of the films occurs at a thickness above 400 nm and, concomitantly, a significant increase of the Eu3+ emission efficiency is detected.
Efficient Hybrid‐Type CO2 Adsorbents of Reassembled Layered Double Hydroxide 2D Nanosheets with Polyoxometalate 0D Nanoclusters
Authors: Gunjakar Jayavant L. , Kim In Young , Hwang Seong‐Ju
Published: September 2014

Porous nanohybrids of cationic Mg‐Al‐LDH 2D nanosheets and anionic polyoxometalate (POM, V10O286– and W7O246–) 0D nanoclusters are synthesized by an exfoliation–reassembling process. The electrostatically derived reassembling between two kinds of nanostructures yields a layer‐by‐layer‐ordered intercalation structure with porous structures composed of mesopores and micropores. The hybridization with POM leads to the remarkable enhancement of CO2 adsorption capacity (adsorptivity) of Mg‐Al‐LDH by about 10‐fold. Of prime importance is that the CO2 adsorptivity of the nanohybrid is strongly dependent on the type of guest POM species, strongly suggesting that the CO2 adsorptivity of the LDH‐based nanohybrid materials can be optimized by ones selection of guest species. The present study clearly demonstrates that the exfoliation–reassembling method is quite effective at enabling synthesis of new LDH nanosheet‐based hybrid materials with improved CO2 adsorption capabilities.
Barium Titanate Torus‐Like Particles: Low‐Temperature Synthesis and Formation Mechanism
Authors: Maxim Florentina , Poenaru Iuliana , Teodorescu Florina , Tanasescu Speranta
Published: September 2014

This work aims to clarify the mechanism of formation of torus‐like barium titanate (BaTiO3) particles with a view to evaluating the properties of these hollow perovskite oxide crystals. Crystalline BaTiO3 powders have been synthesized by hydrothermal treatment of titanium‐based nanotubes and barium chloride in alkaline media at 90, 110 and 200 °C for various reaction times. The possibility of obtaining hollow barium titanate particles at intermediate stages of crystallization by a low‐temperature template‐free process is demonstrated. The formation of a hollow in the centre of the particles is attributed to the Kirkendall effect associated with the different diffusion rates of Ba2+ and Ti4+ hydrothermal species through the (010) crystallographic plane of the BaTiO3 lattice and with the formation of vacancies.
Theoretical Design of cis‐Bis(imido)uranium Iodides – Electronic Structures and Spectroscopic Properties
Authors: Lv Chun‐Mei , Pan Ling‐Chao , Pan Qing‐Jiang , Guo Yuan‐Ru , Zhang Hong‐Xing
Published: September 2014

To understand the structural and electronic properties of uranium complexes, the cis‐bis(imido)uranium iodides cis‐[U(NPh)2(THF)3I2] (3Ph) and cis‐[U(NPh)2(THF)2I2] (2Ph) have been designed, and their structures and properties have been calculated by density functional theory (DFT) and time‐dependent DFT. Four isomers (3Ph1, 3Ph2, 2Ph1, 2Ph2) were addressed in the study; these isomers have the structural feature that one iodide atom is trans to one imido group in the axial direction, and the other iodine atom is cis to the other imido group in the equatorial plane. The total system energies, geometry parameters, and vibrational spectra were similar among the respective isomers. Analyses of the electronic structures in tetrahydrofuran solution revealed that these isomeric complexes show mixed π(U=N) and π(Ph) character for the highest occupied molecular orbital (HOMO) and HOMO–1; the lone pairs of electrons of the iodine atom are dominant in the energetically lower occupied orbitals. U(f)‐type orbitals contribute to the low‐lying unoccupied orbitals, as has been generally accepted for analogous hexavalent trans‐dioxouranium complexes. Three main absorption peaks were observed for 3Ph1/3Ph2 and 2Ph1/2Ph2 from time‐dependent long‐range‐corrected functional calculations. The first one originates from the π(U=N) bonds and the phenyl groups, and the third is related to character of the iodine atoms [σ(U–I) and π(I)]; combined π(I) and π(U=N) character is attributed to the middle peak. We also calculated the experimentally known trans‐U(NPh)2(THF)3I2 (trans‐3Ph). The comparison of trans‐3Ph, 3Ph1, and 3Ph2 indicates that the cis/trans isomerism has a relatively large effect on their structural and electronic properties.
Revisiting the Synthesis of 4,6‐Difluorobenzofuroxan: A Study of Its Reactivity and Access to Fluorinated Quinoxaline Oxides
Authors: Jovené Cyril , Jacquet Morgane , Marrot Jérome , Bourdreux Flavien , Kletsky Mikhail E. , Burov Oleg N. , Gonçalves Anne‐Marie , Goumont Régis
Published: September 2014

New quinoxaline 1,4‐dioxide derivatives have been synthesized from novel fluorinated benzofuroxans such as 4‐fluorobenzofuroxan, which is prepared for the first time. Furthermore, the preparation 4,6‐difluorobenzofuroxan has been revisited because we were unable to reproduce the reported synthetic method. Several synthetic pathways have thus been investigated, and the optimal way to prepare this disubstituted benzofuroxan was from the 3,5‐difluoro‐2‐nitroaniline. The various synthetic attempts have allowed the isolation of interesting new compounds such as hydroxybenzotriazole‐like heterocycles or benzoquinone 2‐diazide. In the latter case, our study reveals some interesting features in the mechanism of their formation. The first structural elucidation of benzoquinone 2‐diazide through an X‐ray crystallographic study is also reported. This study has unambiguously shown that benzoquinone 2‐diazide can be involved in Diels–Alder reactions. The first case of a reaction involving a nitro‐substituted benzoquinone 2‐diazide and cyclopentadiene is also reported. To understand better the influence of the fluorine atoms on the reactivity of benzofuroxans and benzofurazans, a wide array of new fluorinated heterocycles were synthesized together with some already known compounds. This has enabled an extensive investigation of their electrophilic behavior to be undertaken through a theoretical and an electrochemical study. From these studies, it could be deduced that the replacement of nitro groups by fluorine atoms results in a significant decrease in the electrophilic character of benzofuroxan. Nevertheless, these compounds could undergo SNAr processes, leading to new functionalized heterocycles. The first examples of aromatic nucleophilic substitution of fluorine with these compounds are also described.
Efficient Synthesis of 1,4,7‐Triazacyclononane and 1,4,7‐Triazacyclononane‐Based Bifunctional Chelators for Bioconjugation
Authors: Désogère Pauline , Rousselin Yoann , Poty Sophie , Bernhard Claire , Goze Christine , Boschetti Frédéric , Denat Franck
Published: September 2014

The reaction of diethylenetriamine with chloroacetaldehyde yielded a bicyclic aminal intermediate for the synthesis of 1,4,7‐triazacyclononane (TACN), a macrocyclic polyamine the derivatives of which find applications as catalysts, bleaching agents, and chelators for medical imaging. This new synthetic protocol outperforms the synthetic methods described so far because it does not involve any cyclization step. Moreover, this aminal intermediate allowed access to a new family of TACN derivatives functionalized on the carbon skeleton, for example, C‐aminomethyl‐TACN. This novel compound is a precursor of valuable bifunctional chelating agents for nuclear medicine, in particular, for the preparation of PET imaging agents after bioconjugation and metallation with 68Ga or 64Cu.
Reagent‐Controlled Cyclization–Deprotection Reaction to Yield either Fluorenes or Benzochromenes
Authors: Killander Dan , Sterner Olov
Published: September 2014

Compounds with benzochromene and fluorene structures are common in nature and society, and they can have potentially useful biological activities. In this paper, conditions for the selective preparation of either a benzochromene or a fluorene from the same starting material are described. The procedure uses a reagent‐controlled cyclization–demethylation to give the benzochromene, or an intramolecular Friedel–Crafts‐type alkylation to give the fluorene.
Asymmetric Evans syn‐Aldol Reactions of Terpene‐Derived Enals: Scope and Limitations
Authors: Kriening Sebastian , Evagelou Athanasios , Claasen Birgit , Baro Angelika , Laschat Sabine
Published: September 2014

The (E)‐ and (Z)‐terpene‐based aldehydes 6b and 6c with a silyl ether function in the γ‐position were prepared and investigated in boron‐mediated asymmetric Evans aldol reactions. Screening experiments of chiral N‐acylated oxazolidinones 7, which are conveniently accessible from 5‐methyl‐5‐hexenoic acid and Evans oxazolidinone auxiliaries, with various boron triflates and terpenoid neral (Z)‐6a as aldehyde component, provided conditions in which highly selective formation of syn‐aldol adduct 5a occurred and competing C=C double bond isomerization to 10 was completely suppressed. Applying the optimized conditions to O‐silylated aldehydes 6b and 6c and N‐acyloxazolidinone derivative (R)‐7a confirmed the syn‐selectivity and gave the appropriate products syn‐5b,c and syn‐21b,c in good yields. In the case of neral‐derived syn adduct 5a, the configuration of the new stereogenic centers C‐2/C‐3 could be assigned as (2R,3S).
Lipase‐Catalyzed Synthesis of Substituted Phenylacetamides: Hammett Analysis and Computational Study of the Enzymatic Aminolysis
Authors: García Liñares Guadalupe , Arroyo Mañez Pau , Baldessari Alicia
Published: September 2014

A series of hydroxy‐, methoxy‐, and nitrophenylacetamides was synthesized by enzyme catalysis. The 28 new products were obtained through a lipase‐catalyzed two‐step reaction in very good to excellent yield. In the case of nitro derivatives, a one‐pot, two‐step methodology allowed the desired products to be obtained in high yields. The influence of various reaction parameters in the lipase‐catalyzed reactions, such as enzyme source, nucleophile (alcohol or amine)/substrate ratio, enzyme/substrate ratio, solvent and temperature were studied. It was observed that nitro‐substituted phenylacetates were more reactive in the aminolysis reaction than phenylacetates substituted with a hydroxyl group. To study this substituent effect, a Hammett analysis and the determination of the ρ parameter were carried out. Moreover, a computational study was applied to the most representative systems, performing an exploration of the potential energy surface for the catalyzed and noncatalyzed aminolysis reaction for nitro‐ and hydroxyphenylacetates. Both analysis showed that the presence of a strongly electron‐attracting group favors the activity of the enzyme, in complete agreement with the experimental results of the enzymatic catalysis.
A General Continuous Flow Method for Palladium Catalysed Carbonylation Reactions Using Single and Multiple Tube‐in‐Tube Gas‐Liquid Microreactors
Authors: Gross Ulrike , Koos Peter , O'Brien Matthew , Polyzos Anastasios , Ley Steven V.
Published: September 2014

A series of continuous flow chemistry processes that facilitate the palladium‐catalysed carbonylation of aryl and vinyl iodides and aryl bromides with a range of alkoxy, hydroxy and amino nucleophiles is reported. Harnessing a semipermeable Teflon® AF‐2400 Tube‐in‐Tube assembly, these reactors permit the controlled transport of carbon monoxide into solution at elevated pressure to generate homogeneous flow streams, avoiding some potential issues associated with segmented flow gas‐liquid reactors. As the volume of pressurised gas contained within the device is low, the hazards associated with this are potentially mitigated relative to comparable batch processes. We also show how the incorporation of a second in‐line gas‐flow reactor allows for the sequential introduction of two gases (carbon monoxide and a gaseous nucleophile) into the reaction stream.
Six Peroxide Groups in One Molecule – Synthesis of Nine‐Membered Bicyclic Silyl Peroxides
Authors: Arzumanyan Ashot V. , Terent'ev Alexander O. , Novikov Roman A. , Lakhtin Valentin G. , Chernyshev Vladimir V. , Fitch Andrew N. , Nikishin Gennady I.
Published: September 2014

Compounds containing two nine‐membered peroxide rings bridged by an ethane, ethene, or ethyne group were synthesized by the reactions of 1,2‐bis[dichloro(alkyl)silyl]ethanes, (E)‐1,2‐bis[dichloro(methyl)silyl]ethene, or 1,2‐bis[dichloro(methyl)silyl]ethyne with 1,1′‐dihydroperoxydicycloalkyl peroxides. Each ring is formed by the replacement of two geminal chlorine atoms at the silicon atom with the hydroperoxide groups of one peroxide molecule. The cyclization is regioselective. The possible 12‐membered bicyclic peroxide products are not produced. Unexpectedly, the peroxides are extremely explosive. The reactions of 1,2‐bis[dichloro(alkyl)silyl]ethanes with 1,1‐dihydroperoxy‐tert‐butylcyclohexane give only bicyclic peroxides containing two six‐membered rings also through the replacement of two geminal chlorine atoms at the silicon atom by the hydroperoxide groups of one dihydroperoxide molecule.
Reconsidering remap methods
Authors: Rider William J.
Published: September 2014

Methods for discretizing remap are often based on algorithms developed for hyperbolic conservation laws. Because its introduction in 1977 Van Leer's monotonicity‐preserving piecewise linear method and its extensions have been ubiquitous in remap “Van Leer's fourth paper in his series “Towards the Ultimate””. In that 1977 paper, Van Leer introduced another five algorithms, which largely have not been used for remap despite the observation that the piecewise linear method had the least favorable theoretical properties. This adoption parallels the algorithmic choices in other related fields. Two factors have led to the lack of attraction to the five algorithms: the simplicity and effectiveness of the piecewise linear method and complications in practical implementation of the other methods. Plainly stated, Van Leer's piecewise linear method enabled ALE methods to move forward by providing a high‐resolution, monotonicity‐preserving remap. As a cell‐centered scheme, the extension to remap was straightforward. Several factors may be conspiring to reconsider these methods anew: computing architectures are more favorable toward more floating point intensive methods, methods lacking data movement, and 30 years of experience in devising nonlinear stability mechanisms (i.e., limiters). In particular, one of the methods blends characteristics of finite volume and finite difference methods together in an ingenious manner that has exceptional numerical properties and should be considered as a viable alternative to the ubiquitous piecewise linear method. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Investigating Injury Occurrence in Motor Vehicle Collision Using Artificial Neural Networks
Authors: Liu Dahai , Solomon Desmond , Hardy Leon
Published: September 2014

Vehicle collisions amount to a significant loss of life in America. Upward of 30,000 lives are lost each year in the United States alone. Hundreds of millions of dollars are spent each year on vehicle safety and roadway design in the United States, and many studies have been conducted on the causal factors for vehicle collisions. This study used artificial neural networks as a means to predict the occurrence of injury of a vehicle collision. The objective was to classify the levels of the “injury occurrence” in vehicle collisions, given certain input variables, including demographic and environmental factors involved in crashes. Using Neural Ware's Predict software, a back‐propagation neural network model was constructed, trained, tested, and validated using data from the 2006 and 2007 Florida Traffic Crash Database. The neural network's computational power was iteratively increased by adding hidden layers to boost its predicting power until the performance began to plateau. Classification rates as well as Kolmogorov‐Smirnov (K‐S) statistical analysis were used to validate the model. A sensitivity analysis was then applied to find the level of contribution that the input variables had on the injury occurrence. Accident severity, number of lanes, and road surface conditions were found to have the most positive impacts on the injury occurrence. The implications of the study are discussed at the end of the article.
Viral infections and colorectal cancer: A systematic review of epidemiological studies
Authors: Chen Hongda , Chen Xin‐Zu , Waterboer Tim , Castro Felipe Andres , Brenner Hermann
Published: September 2014

Numerous studies have found the presence of viral DNA in colorectal tumor tissues. However, whether viral infections contribute to the risk of colorectal cancer (CRC) is still under debate. We aimed to provide an overview of published epidemiological studies on the association between viral infections and CRC. A systematic literature search was performed in PubMed to find relevant studies published until 8 May 2014. Information collected included study population, sample type, laboratory method and prevalence of viral infection in cancer or precancer patients and controls. We found 41 studies that fulfilled the selection criteria, all of which had cross‐sectional or case‐control designs, and most of which were of small to moderate size. Viral infections included human papillomaviruses (HPV), human polyomaviruses, human herpesviruses, human bocavirus and Inoue‐Melnick virus. Inconsistent results were observed across studies. Many studies reported higher viral DNA prevalence in tumor tissues than in normal noncancerous tissues either in the same patients or in CRC‐free controls. However, potential contamination or temporal sequence of the infection and cancer development were often unclear. Seroprevalence studies assessing antibody titers indicative of viral infections did not find statistically significant differences between CRC cases and healthy controls. Overall published evidence on the role of viral infections in CRC etiology remains limited. Given the potential importance of viral infections and their implication for prevention, there is a strong need for large, methodologically rigorous epidemiological studies.
Wound healing‐like immune program facilitates postpartum mammary gland involution and tumor progression
Authors: Martinson Holly A. , Jindal Sonali , Durand‐Rougely Clarissa , Borges Virginia F. , Schedin Pepper
Published: September 2014

Women diagnosed with breast cancer within 5 years postpartum have poor survival rates. The process of postpartum mammary gland involution, whereby the lactating gland remodels to its prepregnant state, promotes breast cancer progression in xenograft models. Macrophage influx occurs during mammary gland involution, implicating immune modulation in the promotion of postpartum breast cancer. Herein, we characterize the postpartum murine mammary gland and find an orchestrated influx of immune cells similar to that which occurs during wound healing. Further, the normal involuting gland may be in an immunosuppressed state as discerned by the transient presence of Foxp3+ regulatory T cells and IL‐10+ macrophages with T cell suppressive function. To determine the influence of the postpartum immune microenvironment on mammary tumor promotion, we developed an immune‐competent model. In this model, mammary tumors in the involution group are sixfold larger than nulliparous group tumors, have decreased CD4+ and CD8+ T cell infiltrates and contain a greater number of macrophages with the ability to inhibit T cell activation. Targeting involution with a neutralizing antibody against the immunosuppressive cytokine IL‐10 reduces tumor growth in involution group mice but not in nulliparous mice, implicating the involution microenvironment as the primary target of αIL‐10 treatment. Relevance to women is implicated, as we find postlactational human breast tissue has transient high IL‐10+ and Foxp3+ immune cell infiltrate. These data show an immune modulated microenvironment within the normal involuting mammary gland suggestive of immunosuppression, that when targeted reduces tumor promotion, revealing possible immune‐based strategies for postpartum breast cancer.
Skin absorption of six performance amines used in metalworking fluids
Authors: Roux Lauriane N. , Brooks James D. , Yeatts James L. , Baynes Ronald E.
Published: September 2014

Every year, 10 million workers are exposed to metalworking fluids (MWFs) that may be toxic. There are four types of MWFs: neat oils and three water‐based MWFs (soluble oil, semisynthetic and synthetic), which are diluted with water and whose composition varies according to the mineral oils ratio. MWFs also contain various additives. To determine the absorption of six amines used as corrosion inhibitors and biocides in MWFs, porcine skin flow‐through diffusion cell experiments were conducted with hydrophilic ethanolamines (mono‐, di‐ and triethanolamine, MEA, DEA and TEA respectively) and a mixture of lipophilic amines (dibutylethanolamine, dicyclohexylamine and diphenylamine). The six amines were dosed in four vehicles (water and three generic water‐based MWF formulations) and analyzed using a scintillation counter or gas chromatography/mass spectrometry. These 24 h studies showed that dermal absorption significantly (P < 0.05) increased from water for the six amines (e.g. 1.15 ± 0.29% dose; DEA in water) compared to other formulations (e.g. 0.13 ± 0.01% dose; DEA in semisynthetic MWF) and absorption was greatest for dibutylethanolamine in all the formulations. The soluble oil formulation tended to increase the dermal absorption of the hydrophilic amines. The permeability coefficient was significantly higher (P < 0.05) with TEA relative to the other hydrophilic amines (e.g. 4.22 × 10–4 ± 0.53 × 10–4 cm h–1 [TEA in synthetic MWF] vs. 1.23 × 10–4 ± 0.10 × 10–4 cm h–1 [MEA in synthetic MWF]), except for MEA in soluble oil formulation. Future research will confirm these findings in an in vivo pig model along with dermatotoxicity studies. These results should help MWF industries choose safer additives for their formulations to protect the health of metalworkers. Copyright © 2014 John Wiley & Sons, Ltd.