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Hrdina Radim - - 2011
We present a new class of catalysts based on the combination of N,N'-diaryl(thio)ureas and weak silicon Lewis acids (e.g., SiCl(4)). Such silicon-(thio)urea catalysts effectively catalyze the stereospecific rearrangement of epoxides to quaternary carbaldehydes.
Tava Aldo - - 2011
The saponin composition of leaves from the Medicago polymorpha cultivars 'Santiago' and 'Anglona' belonging to the botanical varieties brevispina and vulgaris, respectively, was investigated by a combination of chromatographic, spectroscopic and spectrometric techniques. Several compounds were detected and quantitated by HPLC analysis using the external standard method. Twelve triterpene saponins ...
Zhong Ying - - 2011
Epigallocatechin gallate (EGCG) is the major polyphenol in green tea and known to render many health benefits associated with tea consumption. EGCG was modified structurally in order to improve its lipophilicity and expand its application in lipophilic media and enhance its cellular absorption in vivo. Esterification of the water-soluble EGCG ...
Fukuyama Takayuki - - 2011
The electronic circular dichroism (ECD) spectra of three L-hydroxy acids (L-lactic acid, (+)-(S)-2-hydroxy-3-methylbutyric acid, and (-)-(S)-2-hydroxyisocaproic acid) were measured down to 160 nm in aqueous solution using a vacuum-ultraviolet ECD spectrophotometer. To assign the two positive peaks around 210 and 175 nm and the one negative peak around 190 nm ...
Ogawa Shoujiro - - 2011
The (25R)- and (25S)-epimers of C(27) 3α,7α,12α-trihydroxy-5α-cholestan-27-oic acid as well as their corresponding N-acylamidate conjugates with glycine or taurine were prepared starting from cholic acid in 14 steps. The principal reactions involved were (1) reduction of a key intermediary C(24)allo-cholic acid performate with NaBH(4)/triethylamine/ethyl chloroformate, (2) iodination of the resulting ...
Huang Tengfang - - 2011
Chemical defense against herbivores is of utmost importance for plants. Primary and secondary metabolites, including non-protein amino acids, have been implicated in plant defense against insect pests. High levels of non-protein amino acids have been identified in certain plant families, including legumes and grasses, where they have been associated with ...
Ooi Makoto - - 2011
OBJECTIVE: The roles that amino acids play in immunity and inflammation are well defined, and the relationship between inflammatory bowel disease (IBD) and certain amino acids has recently attracted attention. In this study, the levels of amino acids and trichloroacetic acid (TCA) cycle-related molecules in the colonic tissues and sera ...
Onyango E M - - 2011
The effects of different forms of inositol hexaphosphate (IP6, phytate) on mucin excretion from the digestive tract of ducks were investigated. Forty-eight ten-wk-old male ducks were grouped by weight into eight blocks of six cages with one bird per cage. On the first day of experimentation, birds received by intubation ...
Nunes Patrícia M - - 2011
Ursodeoxycholic acid (UDCA) is commonly used for the treatment of hepatobiliary disorders. In this study, we tested whether a 4-week treatment with this bile acid (12-15 mg/kg/day) could improve hepatic fatty acid oxidation in obese Zucker rats - a model for nonalcoholic fatty liver disease and steatosis. After 24 h of fasting, ...
Jin Li-Qun - - 2011
2-Chloronicotinic acid is receiving much attention for its effective applications as a key precursor in the synthesis of pesticides and medicines. In this study, a strain ZJB-09149 converting 2-chloro-3-cyanopyridine to 2-chloronicotinic acid was newly isolated and identified as Rhodococcus erythropolis, based on its physiological and biological tests, and 16S rDNA ...
Xu Tao - - 2011
A new strategy for the stereoselective total synthesis of natural product pseudolaric acid A (1) was accomplished in 16 steps from commercially available starting material, featuring a samarium diiodide (SmI(2))-mediated intramolecular alkene-ketyl radical cyclization and a ring-closing metathesis (RCM) reaction to stereoselectively cast the unusual trans-fused [5-7]-bicyclic core of pseudolaric ...
Liu Tao - - 2011
An efficient copper-catalyzed method has been developed for the synthesis of poly-N-heterocycles containing amino acid residues. The protocol uses readily available 2-halobenzamides containing amino acids and their methyl esters, substituted phenylacetonitriles, and malononitrile as the starting materials and the reactions were performed well under mild conditions. The method should provide ...
Ito Shosuke - - 2011
Eumelanin and pheomelanin in tissue samples can be specifically measured as the markers pyrrole-2,3,5-tricarboxylic acid (PTCA) and 4-amino-3-hydroxyphenylalanine after acidic permanganate oxidation and hydroiodic acid hydrolysis, respectively. Those degradation methods, although widely applied, are not easily performed in most laboratories. To overcome this difficulty, we developed alkaline H(2) O(2) oxidation ...
Gerszten Robert E RE Cardiology Division and Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital East, Charlestown, MA 02129, USA. - - 2011
In this issue of Science Translational Medicine, Laferrère and colleagues describe a metabolite profiling approach to investigate changes in the circulating metabolome after equivalent weight loss spurred by either gastric bypass surgery (GBP) or dietary intervention. The results reveal that GBP enhances branched chain amino acid metabolism by mechanisms separate ...
Davey Evan A - - 2011
A small array obtained from three reactive cruciform fluorophores in six different solvents discerns ten different aromatic carboxylic acid by protonation-induced fluorescence shifts that are recorded by digital photography. This simple array works even for acids that have closely spaced pKa values.
Friedman Mendel - - 2011
This paper reviews and interprets a method for determining the nutritional value of D: -amino acids, D: -peptides, and amino acid derivatives using a growth assay in mice fed a synthetic all-amino acid diet. A large number of experiments were carried out in which a molar equivalent of the test ...
Tan Chong Kiat - - 2011
An efficient and enantioselective bromolactonization of 1,2-disubstituted olefinic acids using an amino-thiocarbamate catalyst has been developed, resulting in the formation of δ-lactones containing two chiral centers with up to 99% yield, 95% ee.
Tsuchiya Masayuki - - 2011
A novel sensing method for polyhydroxy compounds has been established based on the stimuli-responsive inclusion complex of boronic acid-modified amylose with iodine. An aqueous solution containing the boronic acid-modified amylose and iodine was coloured bluish purple due to encapsulation of iodine within the helical cavity of amylose. When polyhydroxy compounds ...
Tsutsumi Motosuke - - 2011
One of the important secondary structures in proteins is the β-strand. However, due to its complexity, it is less characterized than helical structures. Using the 1,641 representative three-dimensional protein structure data from the Protein Data Bank, we characterized β-strand structures based on strand length and amino acid composition, focusing on ...
Lien Eric Jung-Chi - - 2011
In view of the increasing number of patients undergoing kidney dialysis or transplant every year, a survey of the literature on renal protective medicinal plants was undertaken. Most of them are from traditional Chinese medicine (TCM). Although many of the medicinal herbs reported have not been investigated in terms of ...
Zhu Shuyun - - 2011
In this communication, we demonstrate for the first time the proof of concept that single-walled carbon nanohorns can be used as an effective fluorescent sensing platform for nucleic acid detection with a high selectivity down to single-base mismatch.
Fu Ji-Ya - - 2011
A series of simple chiral primary amino acids were first successfully applied to promote the enantioselective a-amination of branched aldehydes with azadicarboxylates and the desired adducts bearing quaternary stereogenic centers were obtained in excellent yields (up to 99%) and enantioselectivities (up to 97% ee).
Li Fasong - - 2011
In this study, nine perfluorinated compounds (PFCs) were investigated in water and sediment of Haihe River (HR) and Dagu Drainage Canal (DDC), Tianjin, China. The total PFCs in water samples from DDC (40-174ngL(-1)) was much greater than those from HR (12-74ngL(-1)). PFC contamination was severe at lower reaches of HR ...
Zu Yanbing - - 2011
Extensive secondary structures in nucleic acid targets seriously impede the binding of complementary oligonucleotide probes. We report here a method to conduct the detection under extremely low salt conditions where the secondary structures are unstable and more accessible. A new type of nanoparticle probes prepared by functionalizing gold nanoparticles with ...
Kawamoto Jun - - 2011
Shewanella violacea DSS12, a deep-sea bacterium, produces eicosapentaenoic acid (EPA) as a component of membrane phospholipids. Although various isolates from the deep sea, such as Photobacterium profundum SS9, Colwellia psychrerythraea 34H and various Shewanella strains, produce EPA- or docosahexaenoic acid-containing phospholipids, the physiological role of these polyunsaturated fatty acids remains ...
Gangwar Savita - - 2011
Responses of pea (Pisum sativum L.) seedlings to manganese (50, 100 and 250 μM) and indole acetic acid (10 and 100 μM) treatments were investigated. Single and combined exposure of pea to manganese and 100 μM indole acetic acid decreased root and shoot fresh mass, chlorophyll, carotenoids, protein and nitrogen while ammonium content ...
Tomita Kengo - - 2011
BACKGROUND/AIMS: Serum free fatty acid (FFA) composition and abnormal fatty acid metabolism have been implicated in the pathogenesis of nonalcoholic steatohepatitis (NASH). Therefore, we determined if the serum FFA composition can provide accurate diagnosis of NASH. METHODS: We compared fasting serum FFA compositions in 20 patients with simple steatosis to ...
Bhat Rajeev - - 2011
Freshly squeezed kasturi lime fruit juice was sonicated (for 0, 30 and 60min at 20°C, 25kHz frequency) to evaluate its impact on selected physico-chemical and antioxidant properties, such as pH, °Brix, titratable acidity, Hunter color values (L(∗), a(∗), b(∗)), ascorbic acid, DPPH radical scavenging activity, total phenolics, antioxidant capacity, flavonoids ...
Zeng Ying Y Department of Physiological Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, United - - 2011
Myelin associated glycoprotein (Siglec-4) is a myelin adhesion receptor, that is, well established for its role as an inhibitor of axonal outgrowth in nerve injury, mediated by binding to sialic acid containing ligands on the axonal membrane. Because disruption of myelin-ligand interactions promotes axon outgrowth, we have sought to develop ...
Ferreira Pablo Gomes - - 2011
This study aimed to evaluate the potential of soybean-promoted acidic nitrite reduction and to correlate this activity to the content of phenolics and to the bactericidal activity against <i>Escherichia coli</i> O157:H7. Extracts of embrionary axes and cotyledons enriched in phenolics increased NO formation at acidic pH at values that were ...
Khan Abad - - 2011
A fast, simple, and a reliable high-performance liquid chromatography linked with electrochemical detector (HPLC-ECD) method for the assessment of lipoic acid (LA) and dihydrolipoic acid (DHLA) in plasma was developed using naproxen sodium as an internal standard (IS) and validated according to standard guidelines. Extraction of both analytes and IS ...
Sato Chizuru - - 2011
Treating the leaves of sweet pepper (Capsicum annuum L. var. grossum) with an aqueous solution of cellulase resulted in a four-fold increase in the salicylic acid level compared to a control plant. The level of endogenous azelaic acid was also elevated by the cellulase treatment. Azelaic acid has recently been ...
Hu Junli - - 2011
Site-specific PEGylation offers the possibility to modify a therapeutic protein without interfering with its biological activity. Previously, a preferential N-terminal PEGylation has been reported for several proteins when the reaction was performed at acidic pH. In the present study it was explored if acidic pH favors N-terminal PEGylation of bone ...
Huang Meng-Chuan - - 2011
Long chain polyunsaturated fatty acids (LC-PUFA), ARA (arachidonic acid, 20:4n-6) and DHA (docosahexaenoic acid, 22:6n-3) have positive effects and environment pollutants, polychlorinated dibenzo-p-dioxins/dibenzofurans(PCDD/F) and polychlorinated biphenyls (PCB) have negative effects on neural development during early life. Placental dioxin/PCB serves as markers for cumulative exposure to fetus. Fatty acid composition of ...
Kabasawa Sho - - 2011
PURPOSE:: To assess modifiable environmental risk factors and protective factors for age-related macular degeneration (AMD) in a native Japanese population. DESIGN:: A case-control study. PARTICIPANTS:: We included 422 case-control samples composed of 279 consecutive AMD cases and 143 controls. METHODS:: Information regarding systemic conditions and lifestyle were documented in each ...
Kikuchi Naoya - - 2011
The Japanese mealybug, Planococcus kraunhiae, is suitable as a model insect for biosynthetic studies on mealybug pigments. Four yellow pigments, including two novel ones, were isolated from the mealybug bodies and characterized as endocrocin, a dicarboxylic acid named fujikonaic acid (1), emodin 1-O-β-D-glucopyranoside and 7-hydroxyemodin 1-O-β-D-glucopyranoside (2). The enzymatic activity ...
Takahashi Hideki - - 2011
We investigated the effects of various cyclodextrins (CDs) on the aqueous solubility and thermal stability of α-lipoic acid, a compound with low water solubility. α-CD, β-CD, and γ-CD had little effect on the aqueous solubility of α-lipoic acid. In contrast, 6-O-α-maltosyl-CDs increased it in a concentration-dependent manner, 6-O-α-maltosyl-β-CD enhancing solubility ...
Bolte Benoit - - 2011
A series of allenyl ethers can be transformed into various fused or spiro tetrahydrofurans and tetrahydropyrans following a hydride shift/cyclization sequence. A divergence in product selectivity, that depends on the nature of the catalyst used (Au(I) complex or Brønsted acid), was observed.
Nagao Seiya - - 2011
This study reports carbon isotopic ratios (Δ(14)C and δ(13)C) of dissolved humic and fulvic acids in the Tokachi River system, northern Japan. These acids have a refractory feature and they represent the largest fraction of dissolved organic matter in aquatic environments. The acids were isolated using the XAD extraction method ...
Erb Jeremy - - 2011
We report in full detail our studies on the catalytic, asymmetric α-fluorination of acid chlorides, a practical method that produces an array of α-fluorocarboxylic acid derivatives in which improved yield and virtually complete enantioselectivity are controlled through electrophilic fluorination of a ketene enolate intermediate. We discovered, for the first time, ...
Ding Hui H Department of Neurosurgery, Cedars-Sinai Medical Center, 110 N. George Burns Rd, Davis 2094A, Los Angeles, CA 90048, USA. - - 2011
Membranolytic macromolecules are promising vehicles for cytoplasmic drug delivery, but their efficiency and safety remains primary concerns. To address those concerns, membranolytic properties of various poly(β-L-malic acid) (PMLA) copolymers were extensively investigated as a function of concentration and pH. PMLA, a naturally occurring biodegradable polymer, acquires membranolytic activities after substitution ...
Ma Tian-Yi - - 2011
Hierarchically macro-/mesoporous titanium phosphonates with enlarged H(+) exchange capacity were synthesized in the presence of a series of alkyl amines that acted as protective groups for the defective P-OH, which were used as promising solid acid catalysts to replace conventional liquid acid catalysts and acidic resins in some acid-catalytic reactions.
Hu Baichuan - - 2011
A mixture of isobutyric acid + water has an upper consolute point at 38.8 mass % isobutyric acid and temperature near 26 °C. Nickel (II) oxide dissolves in this mixture by reacting with the acid to produce water and nickel isobutyrate. The solubility of nickel (II) oxide in isobutyric acid + water ...
Ihara Hideki - - 2011
Anthranilamide (AAM) serves as a bifunctional modifier on the boron atom in catalytic transformations of arylboronic acids. It makes boronyl groups unreactive in Suzuki-Miyaura coupling and promotes Ru-catalyzed ortho-silylation. Suzuki-Miyaura coupling of AAM-modified bromophenylboronic acids with tolylboronic acid gave 1,1'-biaryl-4-boronic acid bearing AAM on the boron atom, which subsequently underwent ...
Miyamoto Yuji - - 2011
Arundic acid, (R)-(-)-2-propyloctanonic acid, is a novel neurological agent for intractable neurodegenerative diseases. However, arundic acid, an oily drug, has low aqueous solubility and severe bitter/irritating tastes. Consequently, these physicochemical properties of arundic acid need to be improved to develop its pharmaceutical preparations. In the present study, we evaluated whether ...
Macredmond Ruth - - 2011
The limitations and side effects of existing asthma therapies prompt interest in complementary and alternative therapies. Conjugated linoleic acids (CLA) are a family of natural fatty acids found primarily in beef and dairy products. These molecules have a variety of biological properties which suggest potential benefit in asthma, including effects ...
Wengryniuk Sarah E - - 2011
The first general method for the asymmetric α,α-bisalkylation of ketones having both α- and α'-protons is described. Both excellent regio- and stereoselectivity result. The transformation is enabled by complex-induced syn-deprotonation (CIS-D), which completely reverses the inherent preference of LDA to remove the least sterically hindered of two similarly acidic protons. ...
Tsourdi Elena - - 2011
Context: Bisphosphonates represent potent antiresorptive drugs that are established for therapy of patients with benign and malignant bone diseases. Zoledronic acid is an iv aminobisphosphonate that is administered annually against osteoporosis. Because of its potency and the parenteral route of administration, zoledronic acid is an alternative to oral bisphosphonates, in ...
Du Ni - - 2011
In this paper, the preparation of new supported ionic liquids (SILs) composed of the N-methylimidazolium cation and the quinoline cation is described. They have been confirmed and evaluated by infrared spectroscopy, elemental analysis and thermogravimetric analysis. Six kinds of different SILs included SiO(2)·Im(+)·Cl(-), SiO(2)·Im(+)·BF(4)(-), SiO(2)·Im(+)·PF(6)(-), SiO(2)·Qu(+)·Cl(-), SiO(2)·Qu(+)·BF(4)(-) and SiO(2)·Qu(+)·PF(6)(-). The ...
Zafarani-Moattar Mohammed Taghi - - 2011
In biotechnology, extraction by means of aqueous biphasic systems (ABS) is known as a promising tool for the recovery and purification of bio-molecules. Over the past decade, the increasing emphasis on cleaner and environmentally benign extraction procedures has led to enhanced interest in the ABS containing ionic liquids (ILs)-a new ...
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