Search Results
Results 1 - 50 of 1632
1 2 3 4 5 6 7 8 9 10 >
Tapia Rubén - - 2014
The first synthesis of spiro lactone (+)-vitedoin B (14 steps, 8.0 % global yield) and spiro enol ether (+)-negundoin A (19 steps, 3.7 % global yield), via a nor-labdane acetoxy ester, has been achieved starting from commercial (+)-abietic acid.
Torricelli Fabio Cesar Miranda FC Stevan B. Streem Center for Endourology and Stone Disease, Glickman Urological & Kidney Institute, The Cleveland Clinic, Cleveland, OH; Division of Urology, Hospital das Clinicas, University of Sao Paulo Medical School, São Paulo, São Paulo, - - 2014
To study several measurements from a single-energy noncontrast computed tomography (NCCT) that may distinguish calcium oxalate, uric acid, and cystine stones. Patients with pure urinary stones who had at least 1 single-energy NCCT before the stone composition analysis from January 2008 to December 2012 were enrolled in this study. The ...
Silveira-Dorta Gaston - - 2014
Enantiomerically pure anti-β-amino alcohols were synthesized from optically pure alpha-N,N-dibenzylamino benzyl esters, derived from alpha-amino acids, by the sequential reduction to aldehyde with DIBAL-H at -78 °C, and subsequent in situ addition of Grignard reagents. Besides anti-β-amino alcohols, anti-2-amino-1,3-diols, and anti-3-amino-1,4-diols, in good yields (60-95%) and excellent stereoselectivity (de > ...
Li Hongmei - - 2014
A synthetic method to prepare a core-shell-structured Fe3O4@SiO2 as a safe nanovehicle for tumor cell targeting has been developed. Superparamagnetic iron oxide is encapsulated inside nonporous silica as the core to provide magnetic targeting. Carboxymethyl chitosan-folic acid (OCMCS-FA) synthesized through coupling folic acid (FA) with OCMCS is then covalently linked ...
Ouchi Hitoshi H School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, - - 2014
Practical total syntheses of acromelic acids A (1) and B (2), which have potent neuro-excitatory activity, were accomplished in 13 (36% total yield) and 17 steps (6.9% total yield), respectively, from 2,6-dichloropyridine (8). Regioselective transformation of symmetric 8 provided nitroalkenes 15 and 16. The pyrrolidine ring was efficiently constructed by ...
Palusiak Agata A Department of General Microbiology, Institute of Microbiology, Biotechnology and Immunology, University of Łódź, Łódź, - - 2014
Most Proteus lipopolysaccharides (LPSs) contain uronic acids or their amides with different amino acids, which together with other negatively charged components account for the acidic character of such LPS molecules. Previous studies have shown the significance of an amide of galacturonic acid with lysine [D-GalA(L-Lys)] for serological specificity of O-antigens ...
Abbasov Mikail E - - 2014
α,β-Unsaturated acylammonium salts, generated in situ from commodity acid chlorides and a chiral isothiourea organocatalyst, comprise a new and versatile family of chiral dienophiles for the venerable Diels-Alder cycloaddition. Their reactivity is unveiled through a highly diastereo- and enantioselective Diels-Alder-lactonization organocascade that generates cis- and trans-fused bicyclic γ- and δ-lactones ...
Luu Stephanie S Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT - - 2014
A major event in the nutrient germination of spores of Bacillus species is release of spores' large depot of dipicolinic acid (DPA). This event is preceded by both commitment, in which spores continue through germination even if germinants are removed, and loss of spore heat resistance. The latter event is ...
Pulido Daniel D Combinatorial Chemistry Unit, Barcelona Science Park , 08028 Barcelona, - - 2014
A highly versatile synthetic strategy is described to generate multimodal and multivalent platforms based on a diethylenetriaminepentaacetic (DTPA) core. Compounds with different functionalization patterns, from mono- to pentamodal, have been prepared using robust and simple chemistry.
Qin Tian T Department of Chemistry and Center for Chemical Methodology and Library Development (CMLD-BU), Boston University, 590 Commonwealth Avenue, Boston, MA 02215 - - 2014
Total syntheses of the dimeric tetrahydroxanthone natural products secalonic acids A and D are described. Key steps involve kinetic resolution of the tetrahydroxanthone core structure using homobenzotetramisole catalysis and late-stage copper(I)-mediated homodimerization of complex aryl stannane monomers.
Lelle Marco M Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, - - 2014
We describe the synthesis and characterization of a new lysine-based heterofunctional cross-linking reagent. It carries two readily available aminooxy functionalities and an activated and protected thiol group that is capable of generating reducible disulfides, the former enable bioorthogonal modification of ketones and aldehydes by the formation of an oxime bond. ...
Soto-Cerda Braulio J BJ Department of Plant Science, University of Manitoba, 66 Dafoe Road, Winnipeg, MB, R3T 2N2, - - 2014
The identification of stable QTL for seed quality traits by association mapping of a diverse panel of linseed accessions establishes the foundation for assisted breeding and future fine mapping in linseed. Linseed oil is valued for its food and non-food applications. Modifying its oil content and fatty acid (FA) profiles ...
Kalina Warren Vincent WV Diagnostic Systems Division, United States Army Medical Research Institute of Infectious Disease, Fort Detrick, MD - - 2014
Magnetic beads offer superior impurity removal and nucleic acid selection over older extraction methods. The easyMAG®, MagNA Pure, EZ1 Advanced-XL, and Arrows' nucleic acid extraction performance of biothreat agents in blood or buffer was evaluated. All instruments showed excellent performance in blood; however, the easyMAG® had best precision and versatility.
Wu Hao H Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People's Republic of - - 2014
In this study we comparatively investigate the removal of humic acids with Fe@Fe2O3 core-shell nanowires under anoxic and oxic conditions. The products of humic acids after reacting with Fe@Fe2O3 core-shell nanowires under anoxic and oxic conditions were carefully examined with three-dimensional excitation emission matrix fluorescence spectroscopy and gas chromatography mass ...
Coogan Michael P MP School of Chemistry and Chemical Biology, University of Lancaster, Lancaster, LA1 4YB, - - 2014
Single amino acid chelates (SAACs) and SAAC-like bifunctional ligands can be exploited in the design of a variety of bioconjugates for facile metallation with the M(CO)3 (+) unit with M = (99m) Tc or Re. When the donor groups of the ligand are quinolone, thiazole or other similarly conjugated heterocycles, the rhenium ...
Keith John M JM Janssen Research and Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA. Electronic address: - - 2014
A series of mechanism based heteroaryl urea fatty acid amide hydrolase (FAAH) inhibitors with spirocyclic diamine cores is described. A potent member of this class, (37), was found to inhibit FAAH centrally, elevate the brain levels of three fatty acid ethanolamides [FAAs: anandamide (AEA), oleoyl ethanolamide (OEA) and palmitoyl ethanolamide ...
Fang Jidun J State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta, Binzhou University, Binzhou, Shandong Province 256600, - - 2013
The distribution and compound-specific carbon isotope ratios of n-alkanes and fatty acids in a sediment core (63cm) collected from Lake Dianchi were examined to investigate organic matter sources in the eutrophic lake. Fatty acids included free and bound fatty acids. The carbon isotope compositions of individual n-alkanes and fatty acids ...
Wang Xiao-Ping - - 2013
The use of snow and ice cores as recorders of environmental contamination is particularly relevant for per- and polyfluoroalky substances (PFASs) given their production history, differing source regions and varied mechanisms driving their global distribution. In a unique study perfluoroalkyl acids (PFAAs) were analysed in dated snow-cores obtained from high ...
Parmar Dixit D Institut für Organische Chemie, RWTH Aachen University, Landoltweg 1, 52074 Aachen (Germany), Fax: - - 2013
Catalytic fluorolactonisations of aromatic carboxylic acids have been developed. The reactions proceed under mild conditions using the commercially available reagent Selectfluor. A weak phase transfer of the reagent mediated by Na2 CO3 allows the reaction to be conducted in non-polar solvents. Furthermore, by the use of a catalytic amount of ...
Andrés Miriam - - 2013
In this manuscript, the synthesis and biological activity of a series of pyrazole acetic acid derivatives as CRTh2 antagonists is presented. Biological evaluation in vitro revealed that the pyrazole core showed in several cases a different structure-activity relationship (SAR) to that of related indole acetic acid. A potent series of ortho-sulfonyl ...
Pett Christian - - 2013
By displaying different O-glycans in a multivalent mode, mucin and mucin-like glycoproteins are involved in a plethora of protein binding events. The understanding of the roles of the glycans and the identification of potential glycan binding proteins are major challenges. To enable future binding studies of mucin glycan and glycopeptide ...
Zheng Fang-Cai - - 2013
The Fe3O4@C core-shell magnetic nanoparticles with an average size of about 190 nm were synthesized via a one-pot solvothermal process using ferrocene as a single reactant. The sulfonic acid-functionalized Fe3O4@C magnetic nanoparticles were obtained by grafting the sulfonic groups on the surface of Fe3O4@C nanoparticles to produce magnetically recyclable solid ...
Huang Huachao - - 2013
Ha72 of Helicoverpa armigera nucleopolyhedrovirus (a homologue of ac78) was identified as a conserved late baculovirus gene and characterized. HA72 localizes in the intranuclear ring zone. By generating mutants, we showed that HA72 is essential for BV production and ODV occlusion. HA72 also interacted with P33, a baculoviral sulfhydryl oxidase. ...
Hisamatsu Yosuke - - 2013
Four arms: A quadruple zwitterion based on a pentaerythritol core forms thermoreversible gels in DMSO driven by the formation of ion-paired dimers between the zwitterionic units. Furthermore, it exhibits reversible gel-sol transitions in response to both acid and base.
Lodowska Jolanta - - 2013
The sugar 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) is a characteristic component of bacterial lipopolysaccharide (LPS, endotoxin). It connects the carbohydrate part of LPS with C6 of glucosamine or 2,3-diaminoglucose of lipid A by acid-labile α-ketosidic linkage. The number of Kdo units present in LPS, the way they are connected, and the occurrence ...
Padala Kishor - - 2013
Substituted acetanilides reacted with aromatic acids in the presence of [{RuCl2(p-cymene)}2], AgSbF6 and (NH4)2S2O8 in ClCH2CH2Cl at 100 °C for 24 h yielding ortho-benzoxylated acetanilides in good to excellent yields in a highly regioselective manner via C-H bond activation.
Crosa María José - - 2014
In this study the effect of vacuum frying (VF) and traditional frying (TF) on oil degradation, fatty acid composition and alpha-tocopherol content was investigated. Two different refined sunflower oils were used: sunflower oil with high oleic acid content (HOSO) and sunflower oil with synthetic antioxidant (tertiary-butylhydroquinone) (TBHQ-SO). Oil degradation was ...
Liu Xiaoxuan - - 2013
RNAi-based nucleic acid molecules have attracted considerable attention as compelling therapeutics providing safe and competent delivery systems are available. Dendrimers are emerging as appealing nanocarriers for nucleic acid delivery thanks to their unique well-defined architecture and the resulting cooperativity and multivalency confined within a nanostructure. The present review offers a ...
Pan Miaorong - - 2013
In this work, a core-shell-shell structured boronic acid-functionalized magnetic composite microspheres Fe3O4@SiO2@poly (methyl methacrylate-co-4-vinylphenylbornoic acid) (Fe3O4@SiO2@P(MMA-co-VPBA)) with uniform size and fine morphology were synthesized. Here, Fe3O4 magnetic particles were prepared by a solvothermal reaction while the Fe3O4@SiO2 microspheres with a core-shell structure were obtained by a sol-gel process. And then, ...
Liu Yingle - - 2013
A tunable and highly regio- and diastereoselective addition of acyclic silyl dienolates to several α-fluoroalkyl sulfinylimines was developed. By appropriate choice of the Lewis acid catalyst, two new chiral α-fluoroalkyl amines and were obtained in good yields and excellent diastereoselectivities (up to >99 : 1 dr), respectively.
Lemétais Aurélie - - 2013
Tetra-O-acylated sulfolipids are metabolites found in the cell wall of Mycobacterium tuberculosis, the causative agent of tuberculosis. Their role in pathogenesis remains, however, undefined. Here we describe a novel access to model tetra-O-acylated trehalose sulfate derivatives having simple acyl chains. The trehalose core was regioselectively protected using a tandem procedure ...
Zhu Lizhi - - 2013
A mild and efficient dual-mode Lewis acid induced Diels Alder (DA)/carbocyclization cascade cyclization reaction has been developed for construction of the tricyclic core of ent-kaurenoids in one pot with the aid of a theoretical study on the π,σ-Lewis acidities of a variety of Lewis acids. With ZnBr2 as the dual-mode ...
Ziolkowski Lori A - - 2013
Abstract The hyperarid core of the Atacama Desert is one of the driest and most inhospitable places on Earth, where life is most commonly found in the interior of rocks (i.e., endolithic habitats). Due to the extreme dryness, microbial activity in these habitats is expected to be low; however, the ...
Teichert Johannes F - - 2013
Boronic acid-substituted shapeshifting bullvalenes bearing a 13C label are employed as sensor arrays for polyhydroxylated compounds such as carbohydrates, flavanols and sialic acids. The dynamic nature of the bullvalene core allows for covalent binding to a wide variety of analytes, allowing for specific analyte de- tection by a single NMR ...
Miao Fang - - 2013
Fluorescent imaging of acidic compartments in living cells was carried out successfully by a novel molecule (CAE) that contained a pyridine unit and a carbazole core. As the protonation of the pyridine N atom of CAE, pH-dependent absorption and fluorescence properties were shown with a pKa of 5.47 which matches ...
Dajantaa Katekan K Faculty of Food and Agricultural Technology, Pibulsongkram Rajabhat University, Phitsanulok 65000, - - 2013
Thai traditionally fermented soybean (Thua Nao) has been suggested as a good source of available amino acids and aglycone isoflavones. The objective of this research was to investigate the changes of biochemical and nutritional qualities in aerobic- and vacuum-packed thua Nao during the storage at 4 and 40 degrees C ...
Zähringer Ulrich - - 2013
In Acinetobacter calcoaceticus NCTC 10305 and A. haemolyticus NCTC 10305 lipopolysaccharide (LPS) a Kdo (3-deoxy-d-manno-oct-2-ulosonic acid)-related octulosonic acid (Ko) interlinks the lipid A with the core-oligosaccharide. This Ko replaces the first Kdo (Kdo(I)) attached to the lipid A backbone in the LPS. The only structural difference between Kdo and Ko ...
Zhong Nanjing - - 2013
BACKGROUND: Pure 1, 3-diacylglycerols (1, 3-DAG) have been considered to be significant surfactants in food, cosmetics and pharmaceutical industries, as well as the effect on obesity prevention. METHODS: In this study, a vacuum-driven air bubbling operation mode was developed and evaluated for the enzymatic synthesis of 1, 3-DAG of saturated ...
Moreno Pineda Eufemio E School of Chemistry and Photon Science Institute, The University of Manchester, Oxford Road, Manchester, M13 9PL, - - 2013
The use of 1-amino-1-cyclohexyl phosphonic acid, a functionalised phosphonate, leads to the synthesis of two new structural types for 3d-4f phosphonate cages with unusual structural cores and which show high magnetocaloric effects.
Kaszowska Marta - - 2013
The complete structure of semi-rough lipopolysaccharide (SR-LPS) of Plesiomonas shigelloides CNCTC 39/89 (serotype O37) has been investigated by (1)H and (13)C NMR spectroscopy, matrix-assisted laser-desorption/ionization time-of-flight MS, and chemical methods. The following structure of the single unit of the O-antigen has been established: in which α-d-Lenp is (2S)-O-(4-oxopentanoic acid)-α-d-Glcp residue ...
Liu Yang - - 2013
10-23 DNAzyme has been used as a very good model for exploring the potential of functional nucleic acids. Its 15-mer catalytic core has been demonstrated to be the optimized in vitro selection result. However, with the introduction of protein-like functional groups through 2'-deoxyguanosine analogues, its two highly conserved guanine residues ...
Mizoguchi Tadashi - - 2013
Green photosynthetic bacteria have unique light-harvesting antenna systems called chlorosomes. Chlorobaculum tepidum, a model organism of the bacteria, biosynthesized monogalactosyl- and rhamnosylgalactosyldiacylglycerides possessing a methylene-bridged palmitoleyl group characterized by a cis-substituted cyclopropane ring as the dominant glycolipids of its chlorosome surface. The formation of the cyclopropane ring was chemically inhibited ...
Salman Salih Mahdi - - 2013
Aiming for new glycolipids with enhanced chemical stability and close structural similarity to natural cell membrane lipids for the development of a drug delivery system, we have synthesized double amide analogs of glyco-glycerolipids. The synthesis applied a Staudinger reaction based coupling of a 1,3-diazide with fatty acid chlorides. While the ...
Riss Patrick J - - 2013
The cocaine-derived dopamine reuptake inhibitors FE-β-CIT (8-(2-fluoroethyl)-3-(4-iodophenyl)-8-azabicyclo[3.2.1]octane-2-carboxylic acid methyl ester) (1) and PR04.MZ(8-(4-fluorobut-2-ynyl)-3-p-tolyl-8-azabicyclo[3.2.1]octane-2-carboxylic acid methyl ester) (2) were labelled with (18) F-fluorine using a two-step route. 2-[(18) F]Fluoroethyltosylate and 4-[(18) F]fluorobut-2-yne-1-yl tosylate were used as labelling reagents, respectively. Radiochemically pure (>98%) [(18) F]FE-β-CIT and [(18) F]PRD04.MZ (32-86 GBq/µmol) were obtained after ...
Qian Tao - - 2013
Polypyrrole-reduced graphite oxide core-shell microspheres with high dispersibility were facilely fabricated and were demonstrated to be excellently sensitive for electrochemical detection of nanomolar concentrations of dopamine in the presence of a large excess of uric acid and ascorbic acid.
Samarajeewa Sandani S Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, - - 2013
In this work, degradable cationic shell cross-linked knedel-like (deg-cSCK) nanoparticles were developed as an alternative platform to replace similar nondegradable cSCK nanoparticles that have been utilized for nucleic acids delivery. An amphiphilic diblock copolymer poly(acrylamidoethylamine)(90)-block-poly(DL-lactide)(40) (PAEA(90)-b-PDLLA(40)) was synthesized, self-assembled in aqueous solution, and shell cross-linked using a hydrolyzable cross-linker to ...
Wang Feijun - - 2013
Enantioselective Pd(ii)-catalyzed construction of [3.3.1]-bicyclic ketals from 2-hydroxyphenylboronic acid and enone is reported, yielding enantioenriched [3.3.1]-bicyclic ketals in up to 97% yields and 98% ee.
Zhao Liyan - - 2013
Determination of the concentration of ascorbic acid in a solution has attracted intense recent interest. Here we demonstrate the feasibility of electro-oxidation of ascorbic acid on spherical cobalt core-shell nanoparticles (10-50 nm dia.) prepared by electrochemical deposition on a H-terminated Si(100) substrate. Depth-profiling X-ray photoelectron spectroscopy reveals that these nanoparticles ...
Taufik Epi - - 2013
The biological significance of the tremendous variation in proportions of oligosaccharides and lactose among mammalian milks is poorly understood. We investigated milk oligosaccharides of the striped skunk (Mephitis mephitis) and compared these results to other species of the clade Mustelida. Individual oligosaccharides were identified by proton nuclear magnetic resonance spectroscopy. ...
Wang Zhaofeng - - 2013
The organocatalytic additions of ascorbic acid to various α,β-unsaturated aldehydes via tandem 1,4-conjugate addition/hemiacetalization/hemiketalization were developed, which provided a rapid entry into the 5-5-5 spirodilactone cores of a family of ascorbylated natural products. Based on the described chemistry, total syntheses of leucodrin, leudrin and the proposed structure of dilaspirolactone were ...
1 2 3 4 5 6 7 8 9 10 >