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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 LA School of Geography and Earth Science, McMaster University, Hamilton, Ontario, Canada. - - 2013
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 rate ...
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 ...
de Villiers Marianne M Department of Biochemistry, Stellenbosch University , Stellenbosch 7600, South - - 2013
Pantothenamides are secondary or tertiary amides of pantothenic acid, the vitamin precursor of the essential cofactor and universal acyl carrier coenzyme A. A recent study has demonstrated that pantothenamides inhibit the growth of blood-stage Plasmodium falciparum with submicromolar potency by exerting an effect on pantothenic acid utilization, but only when ...
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 ...
Li Lu - - 2013
Multifunctional fluorescent-magnetic pH-responsive eccentric-(concentric-Fe(3)O(4)@SiO(2))@polyacrylic acid core-double shell nanocomposites (NCs) have been prepared for simultaneous cell imaging and pH-responsive drug delivery. To confirm the universality of the synthetic concept, the synthetic strategy was also extended to fabricate monodisperse eccentric-(concentric-NaYF(4):Yb/Er/Gd@SiO(2))@polyacrylic acid core-double shell NCs.
Tambo Koharu - - 2013
Human amyloid-β peptide 1-42 (Aβ) was subjected to a radical reaction by using ascorbic acid and CuCl(2). The percentage of D-aspartic acid (D-Asp) after 24 h had increased to 6.69 ± 0.09%, this being comparable with the reported D-Asp concentration of purified core amyloids in Alzheimer's disease patients. This racemization ...
Wang Ming Li - - 2013
Peanut seeds contain high amounts of oil and protein as well as some useful bioactive phytochemicals which can contribute to human health. The U.S. peanut mini-core collection is an important genetic resource for improving seed quality and developing new cultivars. Variability of seed chemical composition within the mini-core was evaluated ...
Khamverdi Zahra - - 2013
[This corrects the article on p. 187 in vol. 4, PMID: 23236569.].
Avaji Prakash G - - 2013
Saturated fatty acids (FA) were grafted using tyrosine as a spacer group to the cyclotriphosphazene ring along with equimolar hydrophilic methoxy poly(ethylene glycol) (MPEG) in cis-nongeminal way. Seven new cyclotriphosphazene amphiphiles were prepared from combinations of hydrophilic MPEGs with different molecular weights of 350, 550, 750 and 1000 and four ...
Biermann Michael - - 2013
In this study, a precise and reliable ultra-high performance liquid chromatography (UHPLC) method for the simultaneous determination of non-canonical (norvaline and norleucine) and standard amino acids (aspartic acid, glutamic acid, serine, histidine, glycine, threonine, arginine, tyrosine, methionine, valine, phenylalanine, isoleucine, leucine) in biopharmaceutical-related fermentation processes was established. After pre-column derivatization ...
Falade Olumuyiwa S - - 2013
Methionine, cysteine, tryptophan, and available lysine were determined in Acacia colei and A. tumida seeds and some cereals using chemical methods, and the results were compared to those obtained using an amino acid analyzer. Ba(OH)2 hydrolysis gave the best result of the three methods of hydrolysis (acid, base, and enzyme) ...
Namiki Yoshihisa - - 2013
Lipidic magnetic nanoparticles are a rapid and reliable magnet-guided nucleic acid delivery system, which we have named as "LipoMag" (Namiki et al., Nat. Nanotechnol 4:598-606, 2009). LipoMag is composed of a cationic lipid shell, an oleic acid binder, and an iron oxide nanocrystal core. Through the electrostatic force, positively charged ...
Ono Machiko - - 2013
Alkaline hydrolysis of 4-hydroxy- or/and 5-hydroxy-(2E)-alkenoate followed by acid treatment gave the corresponding (2E)-alkenoic acids which were subjected to lactone formation reaction without further purification. The crude acids were treated with 2,4,6-trichlorobenzoyl chloride in pyridine to afford γ-lactone or δ-lactone, respectively, accompanied by trans-cis isomerization. By this procedure, (±)-(4,5)-trans-5-benzyloxy-2-hexen-4-olide (90% ...
Xu Yawei - - 2013
Glyco-specific enrichment methods for mass spectrometry pretreatment are invaluable for the detection of low abundant glycoproteins or glycopeptides. For example, boronic acid can specifically interact with glycans in nonaqueous or basic aqueous solutions. Here, we describe a glyco-specific enrichment method which uses a boronic acid-functionalized "core-satellite" composite nanoparticle to isolate ...
Szekeres Márta - - 2013
Despite the large efforts to prepare super paramagnetic iron oxide nanoparticles (MNPs) for biomedical applications, the number of FDA or EMA approved formulations is few. It is not known commonly that the approved formulations in many instances have already been withdrawn or discontinued by the producers; at present, hardly any ...
Antunes Luis Caetano M - - 2013
Chagas disease is a trypanosomiasis whose causative agent is the protozoan parasite Trypanosoma cruzi, which is transmitted to humans by hematophagous insects known as triatomines and affects a large proportion of South America. The digestive tract of the insect vectors in which T. cruzi develops constitutes a dynamic environment that ...
Sišková Karolína M - - 2013
Owing to Mössbauer spectroscopy, an advanced characterization technique for iron-containing materials, the present study reveals previously unknown possibilities using l-amino acids for the generation of magnetic particles. Based on our results, a simple choice of the order of l-amino acids addition into a reaction mixture containing ferrous ions leads to ...
Williams John D - - 2013
6-Cyanobenzo[b]furan-2-boronic acid pinacol ester (10) is a potentially useful 2-point scaffold for the construction of specific compounds or compound libraries with benzofuran cores. Using a per-iodination/de-iodination strategy coupled with a Sonogashira alkynylation and Cu-catalyzed heteroannulation, we have developed a procedure that allows the preparation of benzo[b]furan-6-carbonitrile (9) and 6-cyanobenzo[b]furan-2-boronic acid ...
Yanai Hikaru H School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. - - 2013
The reaction of 1,1-bis(triflyl)ethylene generated in situ with enolizable carbonyls yielded δ-oxo-1,1-bis(triflyl)alkane derivatives. Their acidities in both the gas and solution phases were determined.
Gronwald Oliver O BASF SE, GMV/P - B1, 67056 Ludwigshafen, Germany. - - 2013
This article describes the synthesis and characterization of a novel crosslinked polymer with tricyanuric acid core bearing tetrasulfide bridges as a novel redox polymerization electrode material for rechargeable lithium-sulfur batteries. The new material was synthesized by reaction of stoichiometric sulfur monochloride amounts with trithiocyanuric acid and the structure of the ...
Maswal Masrat - - 2013
Citral is a flavour component widely used in food and cosmetic industries, but is chemically unstable and degrades over time in aqueous solutions due to acid-catalysed and oxidative reactions leading to loss of desirable flavour. The present study reveals the effect of non-ionic micellar solutions of Brij30 and Brij35 on ...
Kim Tae Hyun - - 2012
Ethanol production from poplar sawdust using sulfuric acid-assisted continuous twin screw-driven reactor (CTSR) pretreatment followed by simultaneous saccharification and fermentation (SSF) was investigated. Pretreatment with high acid concentration increased the cellulose content in the pretreated solid (74.9-76.9% in the range of 4.0-5.5wt.% H(2)SO(4)). The sugar content (XMG; xylan+mannan+galactan) in the ...
Pott Robert W M - - 2012
The growth of the biodiesel industry, and its concurrent production of glycerol, has lowered the price of glycerol 20-fold. While many options for using this glycerol have been proposed, the size of the waste stream means that generation of fuels is likely to be the only viable route. One such ...
Sun Yanchun - - 2012
A rapid, sensitive, and reliable ultra-performance liquid chromatography (UPLC) coupled with photodiode array detection method was developed for the amino acid analysis of Amur sturgeon (Acipenser schrenckii Brandt). The method uses minimal sample volume and automated online precolumn derivitization of amino acids with fluorescent 6-aminoquinolyl-carbamyl reagent. The chromatographic separation was ...
Janvier Florence F Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2L - - 2013
Elevated red blood cell (RBC) aggregation increases low-shear blood viscosity and is closely related to several pathophysiological diseases such as atherosclerosis, thrombosis, diabetes, hypertension, cancer, and hereditary chronic hemolytic conditions. Non-ionic linear polymers such as poly(ethylene glycol) (PEG) and Pluronic F68 have shown inhibitory effects against RBC aggregation. However, hypersensitivity ...
Kano Koji - - 2012
A supramolecular diatomic receptor, hemoCD, was modified with PEGylated dendrons to extend its circulation time in the bloodstream. The core component was 4-oxo-4-[[4-(10,15,20-tris(4-sulfonatophenyl)-21H,23H-porphin-5-yl)phenyl]amino]butanoic acid (Por-COOH). The building block of the dendrons was Fmoc-4-amino-4-(2-carboxyethyl)heptanedioic acid (FmocTA), which was condensed with α-amino-ω-methoxy-poly(ethylene glycol) (PEG5000-NH2) to yield an FmocG1-dendron. After deprotection, the G1-dendron ...
De Moliner Fabio - - 2012
A concise synthesis of two pharmacologically relevant classes of molecules possessing the imidazoquinoxaline core is reported. The protocol involves use of 1,2-phenylenediamines and glyoxylic acid derivatives, namely ethyl glyoxylate or benzylglyoxamide, along with tosylmethylisocyanides in a microwave-assisted Van Leusen three-component condensation. Subsequent unmasking (Boc removal) of an internal amino-nucleophile promotes ...
Kupal Sidhendra G - - 2012
Chemo-selective chemistry is one of the main synthetic strategies for the design of bioactive constructs. In this contribution we report on the fabrication of core-shell microgel particles, obtained by "click chemistry" and "inverse emulsion droplets" technique. Azido and alkyne derivatives of poly (vinyl alcohol) (PVA) in a 1:2 mole ratio ...
Kano Taichi - - 2012
An asymmetric synthesis of cyclic amino acids having piperidine and azepane core structures was realized starting from readily available glycine and alanine esters by combination of phase-transfer catalyzed asymmetric alkylation and subsequent reductive amination.
Maity Dipak - - 2012
Core-shell hydrophilic superparamagnetic iron oxide (SPIO) nanoparticles, surface functionalized with either terephthalic acid or 2-amino terephthalic acid, showed large negative MRI contrast ability, validating the advantage of using low molecular weight and π-conjugated canopies for engineering functional nanostructures with superior performances.
Mazzone Jennifer R - - 2012
A synthetic approach to the papyracillic acid family of natural products has been developed. The spiroacetal core is rapidly assembled through an unprecedented zinc carbenoid-mediated tandem chain extension-acylation reaction. Subsequent functional group manipulation provided access to papyracillic acid B and 4-epi-papyracillic acid C. The successful preparation of these molecules resulted ...
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