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Oliw Ernst H EH Division of Biochemical Pharmacology, Department of Pharmaceutical Biosciences, Uppsala Biomedical Center, Uppsala University, 591, 75124, Uppsala, Sweden, - - 2015
Fatty acid oxygenases are often characterized by steric analysis of their hydroxy or hydroperoxy metabolites. Chiral phase-HPLC (CP-HPLC) can be used to separate enantiomeric hydroperoxyoctadecenoic acids. This method is based on analysis of seven octadecenoic fatty acids with double bonds at positions 6Z to 13Z, which were oxidized to hydroperoxides ...
Vignon Paul P UCCS (CNRS-UMR 8181), Université Lille Nord de France, USTL-ENSCL, 59652 Villeneuve d'Ascq - - 2014
The improved catalytic conversion of bioresources, namely unsaturated fatty acid derivatives, is presented. The targeted reaction is ruthenium-catalyzed cross-metathesis with functionalized olefins (α,β-unsaturated esters), that affords shorter diesters. These can be used as biosourced (pre)monomers for the production of polyesters. It is demonstrated that switch from terminal to internal cross-metathesis ...
Sánchez de Medina Verónica V Department of Analytical Chemistry, Annex C-3, Campus of Rabanales, University of Córdoba, Córdoba, Spain; University of Córdoba Agroalimentary Excellence Campus ceiA3; Institute of Biomedical Research Maimónides (IMIBIC), Reina Sofía Hospital, University of Córdoba, E-14071, Córdoba, - - 2014
Recent technological advances to improve the quality of virgin olive oil (VOO) have been focused on olive breeding programs by selecting outstanding cultivars and target progenies. Fatty acids (FAs) composition, with special emphasis on oleic acid (C18:1) and palmitic acid (C16:0), is one of the most critical quality factors to ...
Wang Dingguan - - 2014
Double emulsion has attracted intense scientific investigation on account of their use in a wide range of applications. However, the process of its solidification is usually accompanied by the problem of uncontrollable phase separation. In this work, a supramolecular route is proposed to manage the phase separation in double emulsion. ...
Tarus Dominte D University Grenoble Alpes, CERMAV, F-38000, Grenoble, France; CNRS, CERMAV, F-38000, Grenoble, - - 2014
Dynamic covalent hydrogels are facilely prepared from biocompatible polysaccharides in physiological conditions by the formation of phenylboronate ester cross-links. This is based on the simple mixing of carboxylate-containing polysaccharides (i.e., hyaluronic acid or carboxymethylcellulose) modified with phenylboronic acid and maltose moieties according to mild coupling reactions performed in aqueous solution. ...
Vidal Cristina M P - - 2014
Proanthocyanidins (PACs) are secondary plant metabolites that mediate non-enzymatic collagen cross-linking and enhance the properties of collagen based tissue, such as dentin. The extent and nature of cross-linking is influenced by the composition and specific chemical structure of the bioactive compounds present in certain PAC-rich extracts. This study investigated the ...
Chan-Huot Monique M Laboratoire des BioMolécules, UMR 7203, UPMC/ENS/CNRS, 24, rue Lhomond, 75231 Paris Cedex 05 (France); Sorbonne Universités, UPMC Univ Paris 06, LBM, 4 place Jussieu, 75005, Paris (France); École Normale Supérieure-PSL Research University, Département de Chimie, 24, rue Lhomond, 75005 Paris (France); Institut Curie, 91405 Orsay (France); INSERM U759, 91405 Orsay - - 2014
Deuterium ((2) H) magic-angle spinning (MAS) nuclear magnetic resonance is applied to monitor the dynamics of the exchanging labile deuterons of polycrystalline L-histidine hydrochloride monohydrate-d7 and α-oxalic acid dihydrate-d6 . Direct experimental evidence of fast dynamics is obtained from T1Z and T1Q measurements. Further motional information is extracted from two-dimensional ...
Medeiros D A DA Faculty of Nutrition Federal University of Goias - UFG, Goiânia, Goiás, - - 2014
Background/Objectives:Studies evaluating the effect of folic acid supplementation, either alone or in combination with iron, on the linear and ponderal growth of children are practically nonexistent. The aim of this study was to assess the effect of folic acid supplementation with ferrous sulfate on both linear growth and weight gain ...
Ma Zhong Z Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. - - 2014
A double perovskite oxide Sr2CrMoO6-δ (SCM), synthesized using the sol-gel and annealing method with the assistance of citric acid and ethylene diamine tetraacetic acid, was investigated for the first time as an efficient catalyst for rechargeable lithium air batteries. The SCM cathode enables higher specific capacity, lower overpotential and a ...
Hyun M Y MY Department of Dermatology, Chung-Ang University College of Medicine, Seoul, South - - 2014
Hyaluronic acid (HA) fillers and poly-L-lactic acid (PLA) fillers are frequently used to correct facial wrinkles. To compare the efficacy and safety of a novel injectable poly-L-lactic acid (PLA) filler and a well-studied biphasic HA filler for the treatment of moderate to severe nasolabial folds. In this multicentre, randomized, evaluator-blinded, ...
Lu Xi X Department of Chemistry, University of Science and Technology of China, Hefei 230026 (China); State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Department of Chemistry, Tsinghua University, Beijing 100084 - - 2014
A novel method for the synthesis of non-natural L- and D-amino acids by a Ni-catalyzed reductive cross-coupling reaction is described. This strategy enables the racemization-free cross-coupling of serine/homoserine- derived iodides with aryl/acyl/alkyl halides. It provides convenient access to varieties of enantiopure and functionalized amino acids, which are important building blocks ...
Wang Zhen Z Centre of Basic Molecular Science, Chemistry Department, Tsinghua University , Beijing 100084, - - 2014
Equilibrium acidities (pKa) of 14 aromatic thiols in four pure room temperature ionic liquids (RTILs) were precisely determined and the corresponding acidity scales were established for the first time. Regression analyses show a distinct double-line Hammett relationship with similar slopes and excellent linearity (R(2) of 0.996-0.999) in all four ILs. ...
Manley David W DW University of St. Andrews , EaStCHEM School of Chemistry, St. Andrews, Fife, KY16 9ST, - - 2014
A titania photoredox catalysis protocol was developed for the homocoupling of C-centered radicals derived from carboxylic acids. Intermolecular reactions were generally efficient and selective, furnishing the desired dimers in good yields under mild neutral conditions. Selective cross-coupling with two acids proved unsuccessful. An intramolecular adaptation enabled macrocycles to be prepared, ...
Zhao Xia X College of Chemistry, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, China. - - 2014
Aryl pyrazolone thioethers were synthesized via the I2-catalysed cross-coupling of pyrazolones with aryl sulphonyl hydrazides in the presence of p-toluenesulphonic acid, which has been proposed to promote the reaction by facilitating the decomposition of sulphonyl hydrazides.
Gao Angela X AX Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts, United - - 2014
A panel of acid-labile bis-norbornene cross-linkers was synthesized and evaluated for the formation of acid-degradable brush-arm star polymers (BASPs) via the brush-first ring-opening metathesis polymerization (ROMP) method. An acetal-based cross-linker was identified that, when employed in conjunction with a poly(ethylene glycol) (PEG) macromonomer, provided highly controlled BASP formation reactions. A ...
Salari Pooneh - - 2014
BackgroundIn spite of several studies, the impact of homocysteine level and folic acid supplementation on bone metabolism is yet to be recognized. In this registered clinical trial (IRCT2014042217385N1), we aimed to find out the power of 6-month folic acid supplementation on homocysteine level and bone metabolism.MethodsForty postmenopausal osteoporotic women (50 ...
Zhu Zhi-Qiang ZQ Department of Chemistry, Zhejiang University , Hangzhou, 310028, P. R. - - 2014
A novel dehydrogenative cross-coupling (DCC) reaction between methylquinoline derivatives and N-aryl glycine esters was developed by a cooperative catalysis of copper salt and Brønsted acid, affording an efficient synthesis of β-quinolinyl α-amino acid esters. A plausible mechanism using a proton to activate the methylquinoline derivative and copper(II) to activate N-aryl ...
Thomas Michael C MC Independent Marine Biochemistry Research, Moreton Bay Research Station, Dunwich, QLD, 4183, Australia, - - 2014
The collision-induced dissociation (CID) of cationic fatty acid-metal ion complexes has been extensively studied and, in general, provides rich structural information. In particular, charge-remote fragmentation processes are commonly observed allowing the assignment of double bond position. In a previous manuscript, we presented two methods to doubly deprotonate polyunsaturated fatty acids ...
Liu Yu - - 2014
A Ni-catalyzed direct carboxylation of unactivated primary alkyl bromides and sulfonates with CO2 at atmospheric pressure is described. The transformation is characterized by its mild conditions and a remarkable wide scope without the need for air- or moisture-sensitive reagents, thus becoming a user-friendly and operationally simple protocol en route to ...
Wilkie Lynn M LM Arizona State University, 950 S McAllister, Tempe, AZ, 85282. Electronic address: - - 2014
Complex taste experiences arise from the combinations of five taste primaries. Here we review the literature on binary interactions of heterogeneous taste primaries, focusing on perceptual results of administering mixtures of aqueous solutions to human participants. Some interactions proved relatively consistent across tastants and experimental methods: sour acids enhanced saltiness, ...
Shacklady-McAtee Danielle M DM Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United - - 2014
Highly improved conditions for the enantiospecific cross coupling of benzylic ammonium triflates with boronic acids are reported. This method relies on the use of Ni(cod)2 without ancillary phosphine or N-heterocyclic carbene ligands as catalyst. These conditions enable the coupling of new classes of boronic acids and benzylic ammonium triflates. In ...
Wang Lei L a Division of Applied Science, Graduate School of Agriculture , Hokkaido University , Sapporo , - - 2014
In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable α-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic ...
Mehrparvar Saber S Peptide Chemistry Research Center, K. N. Toosi University of Technology, P. O. Box 15875-4416 , Tehran, - - 2014
Novel analogs of 2-pyridone-3-carboxylic acids 4a-l have been prepared by the three-component reaction of 3-formyl chromone, Meldrum's acid, and primary amines in the presence of a catalytic amount of diammonium hydrogen phosphate in water. Good-to-high yields, easy work-up, and an environmentally friendly profile are the advantages of this method for ...
Gupta Manoj K MK Department of Chemistry, The University of Alabama , Box 870336, Tuscaloosa, Alabama 35487-0336, United - - 2014
Aldehydes and primary alcohols can be converted to one-carbon homologated primary, secondary, or tertiary amides in two operational steps. The approach offers several unique features including compatibility with (hetero)aryl, alkyl, alkenyl, and racemizable chiral substrates, the ability to prepare Weinreb amides from aryl and unhindered aliphatic substrates, and the opportunity ...
Geerts Roy R AkzoNobel N.V., P.O. Box 9300, 6800 SB, Arnhem, The Netherlands, - - 2014
To get insight in the biodegradation and potential read-across of fatty acid amides, N-[3-(dimethylamino)propyl] cocoamide and N-(1-ethylpiperazine) tall oil amide were used as model compounds. Two bacteria, Pseudomonas aeruginosa PK1 and Pseudomonas putida PK2 were isolated with N-[3-(dimethylamino)propyl] cocoamide and its hydrolysis product N,N-dimethyl-1,3-propanediamine, respectively. In mixed culture, both strains ...
Xu Shu S Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan. - - 2014
A novel and efficient transformation of primary alcohols to one-carbon shorter carboxylic acids using IBX is reported. Mechanistic studies revealed that the combination of IBX and molecular iodine produces a different active hypervalent iodine species.
Takase Hiroka H Department of Biophysical Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, - - 2014
Human serum amyloid A (SAA) is a precursor protein of the amyloid fibrils that are responsible for AA amyloidosis. Of the four human SAA genotypes, SAA1 is most commonly associated with AA amyloidosis. Furthermore, SAA1 has three major isoforms (SAA1.1, 1.3, and 1.5) that differ by single amino acid variations ...
Song Qiuling Q Institute of Next Generation Matter Transformation, College of Chemical Engineering at Huaqiao University , 668 Jimei Boulevard, Xiamen, Fujian, 361021, P. R. - - 2014
A Cu2O-catalyzed aerobic oxidative decarboxylative ammoxidation to primary benzamides from phenylacetic acids and α-hydroxyphenylacetic acids is developed. A variety of primary benzamides could be prepared smoothly, in good to excellent yields, by means of a one-pot domino protocol combining decarboxylation, dioxygen activation, oxidative C-H bond functionalization, and amidation reactions.
Bai Jianfei J Laboratoire de Glycochimie et de Synthèse Asymétrique, Swiss Federal Institute of Technology (EPFL) , Batochime, CH 1015 Lausanne, - - 2014
An efficient method has been developed for the direct amidification of carboxylic acids via sulfinylamides preformed in situ by the reaction of pure amines with prop-2-ene-1-sulfinyl chloride. The method can be applied to aliphatic acids, including pivalic acid, aromatic acids, and primary and secondary amines. It is compatible with acids ...
Kumar Vijay V Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla, Himachal Pradesh 171005, - - 2014
β -D-Galactosidases (EC 3.2.1.23) hydrolyze the terminal nonreducing β -D-galactose residues in β -D-galactosides and are ubiquitously present in all life forms including extremophiles. Eighteen microbial β -galactosidase protein sequences, six each from psychrophilic, mesophilic, and thermophilic microbes, were analyzed. Primary structure reveals alanine, glycine, serine, and arginine to be ...
Breslow Ronald R Columbia University, New York City, USA, - - 2013
The synthesis of an excess of D-glyceraldehyde by coupling glycolaldehyde with formaldehyde under prebiotic conditions is catalyzed by L amino acids having primary amino groups at acidic pH's, but at neutral or higher pH's they preferentially form L-glyceraldehyde. L Amino acids having secondary amino groups, such as proline, have the ...
- - 2013
To the Editor: The article on primary hyperoxaluria by Cochat and Rumsby (Aug. 15 issue)(1) contains a misstatement and an omission that require clarification. Contrary to the authors' statement that "oxalate, a dicarboxylic acid," is "highly insoluble," oxalic acid and its sodium salt are quite soluble in water. The toxic ...
Rezvani Iraj - - 2013
To the Editor: The article on primary hyperoxaluria by Cochat and Rumsby (Aug. 15 issue)(1) contains a misstatement and an omission that require clarification. Contrary to the authors' statement that "oxalate, a dicarboxylic acid," is "highly insoluble," oxalic acid and its sodium salt are quite soluble in water. The toxic ...
Dai Ning - - 2013
Concerns have arisen for the possible contamination of air or drinking water supplies downwind of amine-based CO2 capture facilities by potentially carcinogenic N-nitrosamines formed from reactions between flue gas NOx and amine solvents. This study evaluated the influence of amine structure on the potential to form total N-nitrosamines within the ...
Li Yuehui - - 2013
Not a 'B'ore! Benzothiophene-based boronic acids catalyze the reduction of tertiary, secondary, and primary amides in the presence of a hydrosilane. The reaction demonstrates good functional-group tolerance.
Tzin Vered - - 2013
Tomato (Solanum lycopersicum) fruit contains significant amounts of bioactive compounds, particularly multiple classes of specialized metabolites. Enhancing the synthesis and accumulation of these substances, specifically in fruits, are central for improving tomato fruit quality (e.g. flavour and aroma) and could aid in elucidate pathways of specialized metabolism. To promote the ...
Hong Eunyoung E Plant Resources Research Institute, Duksung Women's University, Seoul 132-714, - - 2013
Korean cabbage, a member of the Brassicaceae family which also includes cauliflower, mustard, radish, and turnip plants, is a crucial leafy vegetable crop. Korean cabbage is harvested after completion of the leaf heading process and is often prepared for use in "baechu kimchi", a traditional Korean food. Many of the ...
Blanchard Darian - - 2013
A one-step Bronsted acid-catalyzed synthetic methodology leading to 3-(alkoxymethylene)indolin-2-ones was developed starting from easily accessible 2-hydroxyindole-3-carboxaldehydes. The procedure simply involves a treatment of differently substituted 2-hydroxyindole-3-carboxaldehydes with various alcohols (primary/secondary/tertiary/allyl/propargyl/benzyl) in the presence of a catalytic amount of Bronsted acids such as [Formula: see text]-toluenesulfonic acid and trifluroacetic acid. A ...
Yamashita Risa - - 2013
Primary alkylboronic acids such as methylboronic acid and butylboronic acid are highly active catalysts for the dehydrative amide condensation of α-hydroxycarboxylic acids. The catalytic activities of these primary alkylboronic acids are much higher than those of the previously reported arylboronic acids. The present method was easily applied to a large-scale ...
Tsatsaroni Alexandra - - 2013
An explanation for the vast difference observed in the trypanocidal activity between the new secondary (N-methylated) hydroxamic acids 5 and 6, and their primary (nonmethylated) congeners 1a and 2, based on their E/Z conformational behaviour in DMSO, is presented.
Cui Lingyun - - 2013
Aromatic enamines: para-Vinylanilines were identified as unique nucleophiles, closely resembling enamines, to undergo CC coupling with aldehydes catalyzed by a simple primary-tertiary diamine/Brønsted acid. The resulting bis(allylic) adducts, which have potential as functional materials, were obtained in high yields under rather mild conditions.
Zambroń Bartosz K - - 2013
An efficient method has been developed for the preparation of yet unknown acyclic mixed anhydrides of carboxylic and sulfinic acids. Sterically hindered 2-methylbut-3-ene-2-sulfinyl carboxylates add primary and secondary amines preferentially onto the carbonyl moieties realizing a new method for the one-pot preparation of carboxamides. It uses 1:1 mixtures of carboxylic ...
Lu F S H - - 2013
The main objective of this study was to investigate the oxidative stability and non-enzymatic browning reactions of marine PL in the presence or in the absence of primary amine group from aminophospholipids and amino acids. Marine phospholipids liposomal dispersions were prepared from two authentic standards (phosphatidylcholine and phosphatidylethanolamine) and two ...
Howden Andrew J M - - 2013
Here we demonstrate quantitation of stimuli-induced proteome dynamics in primary cells by combining the power of bio-orthogonal noncanonical amino acid tagging (BONCAT) and stable-isotope labeling of amino acids in cell culture (SILAC). In conjunction with nanoscale liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS), quantitative noncanonical amino acid tagging (QuaNCAT) allowed us to ...
Kakiyama Genta G Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University and McGuire VA Medical Center, Richmond, VA 23249, United - - 2013
The 7α-dehydroxylation of primary bile acids (BAs), chenodeoxycholic (CDCA) and cholic acid (CA) into the secondary BAs, lithocholic (LCA) and deoxycholic acid (DCA), is a key function of the gut microbiota. We aimed at studying the linkage between fecal BAs and gut microbiota in cirrhosis since this could help understand ...
Hyun Myung Ho - - 2013
Liquid chromatographic resolution of racemic compounds containing a primary amino group has been known to be most successful when chiral crown ether-based chiral stationary phases (CSPs) are used. Among various crown ether-based CSPs, the stationary phase based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid covalently bonded to silica gel has been successfully applied in ...
Cal Marta - - 2012
1-[(4-Methylphenyl)oxy]pyrrolidine-2,5-dione and 1-[(4-methylphenyl)oxy]piperidine-2,6-dione react in a Lossen-type reaction with primary alcohols in the presence of triethylamine to furnish corresponding N (α)-urethane-protected β-alanine and γ-aminopropionic acid (GABA), respectively, with excellent yields and purities, in an essentially "one-pot" procedure.
Castellano Teresa G - - 2012
Heterocyclic enols are used for the first time as acid components in an Ugi-type multicomponent condensation. For that purpose, we have chosen enols containing a Michael acceptor, in order to facilitate an irreversible rearrangement of the primary Ugi adduct. The new four-component process leads readily and efficiently to heterocyclic enamines ...
Xu Jun - - 2012
New couple: The Cu-promoted trifluoromethylation of primary and secondary alkylboronic acids with TMSCF(3) extends the scope of transition-metal-catalyzed trifluoromethylation reactions to sp(3) -hybridized carbon centers. It also represents one of the first examples for Cu-catalyzed CC cross-coupling reactions of alkylboronic acid derivatives.
Wang Yong Y Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, Tennessee 38163-0001, - - 2012
Oxyma and an oxyma derivative, (2,2-dimethyl-1,3-dioxolan-4-yl)methyl 2-cyano-2-(hydroxyimino)acetate (5b), displayed a remarkable effect on selective esterifications of primary alcohols. A wide range of carboxylic acids could be esterified with primary alcohols by using EDCI, NaHCO(3), and Oxyma or Oxyma derivative 5b in 5% H(2)O-CH(3)CN. Oxyma derivative 5b is particularly useful, since ...
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