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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 ...
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.
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, ...
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 ...
Agarwal Hitesh K - - 2012
Three fatty acyl conjugates of (-)-2',3'-dideoxy-5-fluoro-3'-thiacytidine (FTC, emtricitabine) were synthesized and evaluated against HIV-1 cell-free and cell-associated virus and compared with the corresponding parent nucleoside and physical mixtures of FTC and fatty acids. Among all the compounds, the myristoylated conjugate of FTC (5, EC50 = 0.07-3.7 µM) displayed the highest ...
Singh Ram B - - 2012
Recent research indicates an association between brain dysfunction and the pathogenesis of metabolic syndrome. To investigate this, we created a Medline search (up to December 2011) of articles in PubMed. The results indicated that refined carbohydrates, saturated and total fat, high levels of ω-6 fatty acids, and low levels of ...
Nosaka Atsuko Y - - 2012
Glutathione is a tripeptide capable of diminishing active oxygen species in living cells. The photocatalytic decomposition glutathione and related amino acids in TiO2 suspension was investigated with 1H NMR spectroscopy. The results suggest that both glutathione in reduced and oxidative forms are adsorbed on the TiO2 surface by carboxyl or ...
Kwon Youngkook - - 2012
This paper addresses the hydrolysis of cellobiose to glucose and its further decomposition with electrochemically generated acid (H(+) ) on a platinum electrode, and with electrochemically generated hydroxyl radicals (OH(.) ) on boron-doped diamond (BDD). The results are compared with the hydrolysis promoted by conventional acid (H(2) SO(4) ) and ...
Kumano O - - 2012
Background: Lupus anticoagulant (LA) is an antibody that interferes with phospholipids dependent coagulation reactions. Activated partial thromboplastin time (APTT) is widely used as a test for LA screening. APTT reagents are composed of activators, such as silica or ellagic acid, and phospholipids, and APTT reagents with silica are recommended for ...
Leung Patrick S C - - 2012
The serologic hallmark of primary biliary cirrhosis (PBC) is the presence of antimitochondrial autoantibodies (AMAs) directed against the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2). The PBC-related autoepitope of PDC-E2 contains lipoic acid, and previous work has demonstrated that mimics of lipoic acid following immunization of mice lead to ...
Huang Xiaoyan - - 2012
BACKGROUND: Stearoyl-CoA desaturase-1 (SCD-1) converts dietary saturated fatty acids to monounsaturated fatty acids. Elevated SCD-1 activity thus signifiesimpaired fatty acid metabolism and excess saturated fat intake. In the general population,increased SCD-1 activity is associated with cardiovascular disease and mortality. The determinants and implications of SCD-1 activity in dialysis patients are ...
Romagnoli Gabriele - - 2012
Fusel alcohols are precursors and contributors to flavor and aroma compounds in fermented beverages, and some are under investigation as biofuels. The decarboxylation of 2-oxo acids is a key step in the Ehrlich pathway for fusel alcohol production. In Saccharomyces cerevisiae, five genes share sequence similarity with genes encoding thiamine ...
Yamanaka Masahiro - - 2012
D: -Amino acids are stereoisomers of L: -amino acids. They are often called unnatural amino acids, but several D: -amino acids have been found in mammalian brains. Among them, D: -serine is abundant in the forebrain and functions as a co-agonist of NMDA receptors to enhance neurotransmission. D: -Amino-acid oxidase ...
Dowling Jennifer K - - 2012
Polyunsaturated fatty acids (PUFA) can modulate the immune response, however the mechanism by which they exert this effect remains unclear. Previous studies have clearly demonstrated that the cis-9, trans-11 isomer of conjugated linoleic acid (c9,t11-CLA), found predominantly in beef and dairy products, can modulate the response of immune cells to ...
Wang Hua - - 2012
An efficient catalytic decarboxylative acylation of unactivated sp(2) (alkenyl) C-H bonds has been developed. Various substituted α-oxocarboxylic acids with different electronic properties react under mild conditions to afford a diverse range of β-acyl enamide products in good yields. The reaction is proposed to proceed via a cyclic vinylpalladium intermediate, facilitating ...
Burney Sarah - - 2012
A quick switch: A single amino acid substitution at a conserved residue (D396N) of Arabidopsis cryptochrome-1 (Atcry1) confers single-stranded DNA repair activity in vitro, conferring photolyase activity onto the cryptochrome. The mutant protein undergoes photoreduction of flavin to the fully reduced anionic form, similar to photolyases and unlike wild-type cryptochromes.
Schriever Sonja C - - 2012
The regulation of cell growth and protein biosynthesis is triggered by the mammalian target of rapamycin complex 1 (mTORC1) responding to amino acids, especially leucine. The molecular mechanisms linking leucine to mTORC1 activation are not well understood. We analyzed whether the free intracellular leucine availability, a metabolite of leucine catabolism ...
Lane Darius J R - - 2012
Vitamin C (ascorbate) plays important neuroprotective and neuromodulatory roles in the mammalian brain. Astrocytes are crucially involved in brain ascorbate homeostasis and may assist in regenerating extracellular ascorbate from its oxidised forms. Ascorbate accumulated by astrocytes can be released rapidly by a process that is stimulated by the excitatory amino ...
Anandan Ramaswamy - - 2012
OBJECTIVES: The aim of the study was to investigate the renoprotective effect of hesperidin (HDN), a citrus flavanoid with anti-oxidant properties against gentamicin (GEN)-induced nephrotoxicity in male Wistar albino rats. METHODS: Urea, uric acid, creatinine, thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), total cholesterol, free fatty acids, and triglyceride ...
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