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Kovács Zita - - 2011
The effect of cold acclimation and abscisic acid (ABA) treatment on the free amino acid composition was compared in Chinese Spring chromosome 5A substitution lines with different levels of freezing tolerance. The total amino acid content gradually increased during the 3-week cold acclimation period, while the effect of ABA became ...
Vaske Yvette S Mimieux - - 2010
Photolysis of alpha-diazo-N-methoxy-N-methyl (Weinreb) beta-ketoamides derived from enantiomerically pure (EP) alpha-amino acids affords the corresponding EP beta-lactams via an intramolecular Wolff rearrangement. The photochemistry is promoted with either standard UV irradiation or through the use of a 100 W compact fluorescent light; the latter affords a safe and environmentally friendly ...
Dückers Nina - - 2010
Threonine aldolases (TAs) constitute a powerful tool for catalyzing carbon-carbon bond formations in synthetic organic chemistry, thus enabling an enantio- and diastereoselective synthesis of beta-hydroxy-alpha-amino acids. Starting from the achiral precursors glycine and an aldehyde, two new stereogenic centres are formed in this catalytic step. The resulting chiral beta-hydroxy-alpha-amino acid ...
Del Rio Daniele - - 2010
This paper reviews recent human studies on the bioavailability of chlorogenic acids in coffee and green tea flavan-3-ols in which the identification of metabolites, catabolites and parent compounds in plasma, urine and ileal fluid was based on mass spectrometric methodology. Both the chlorogenic acids and the flavan-3-ols are absorbed in ...
Khan Zeba - - 2010
The phytochemical investigation of the bark of Tectona grandis Linn. afforded a new steroidal glycoside identified as beta-sitosterol-beta-D-[4'-linolenyl-6'-(tridecan-4'''-one-1'''-oxy)] glucuranopyranoside and three new fatty esters, 7'-hydroxy-n-octacosanoyl n-decanoate, 20'-hydroxy eicosanyl linolenate and 18'-hydroxy n-hexacosanyl n-decanoate, along with the known compounds n-docosane, lup-20(29)-en-3beta-ol, betulinic acid and stigmast-5-en-3-O-beta-D-glucopyranoside. Their stereostructures have been elucidated on ...
Lamers Packo P - - 2010
beta-Carotene is overproduced in the alga Dunaliella salina in response to high light intensities. We have studied the effects of a sudden light increase on carotenoid and fatty acid metabolism using a flat panel photobioreactor that was run in turbidostat mode to ensure a constant light regime throughout the experiments. ...
Wang J - - 2010
A filamentous fungi strain, Aspergillus parasiticus Speare BGB, producing beta-glucuronidase was screened to transform glycyrrhizinic acid (GL) in liquorice into 18-beta-glycyrrhetinic acid (GA). Under the following cultivate conditions in shake flask, 1% GL (purity 30%), medium capacity 40% of flask, the initial pH value at 4.5, cultivate temperature of 32 ...
Tanpure Rajendra P - - 2010
Synthetic routes have been established for the preparation of regio- and stereoisomerically pure samples of the mono-beta-d-glucuronic acid derivatives of combretastatin A-1, referred to as CA1G1 (5a) and CA1G2 (6a). Judicious choice of protecting groups for the catechol ring was required for the regiospecific introduction of the glucuronic acid moiety. ...
Guo Na - - 2010
3-Oxo-oleanolic acid (1) was biotransformed in growing cultures of the fungus Absidia glauca, resulting in three novel hydroxylated metabolites, identified as 1β-hydroxy-3-oxo-olean-11-en-28,13-lactone (2), 1β,11α-dihydroxy-3-oxo-olean-12-en-28-oic acid (3), and 1β,11α,21β-trihydroxy-3-oxo-olean-12-en-28-oic acid (4).
Thasana Nopporn - - 2010
Subtulene A, a new cyclic lipopeptide, was isolated from the culture broth of Bacillus subtilis SSE4. This antibiotic compound contained the seven common alpha-amino acids, L-Asn-1, D-Tyr-2, D-Asn-3, L-Gln-4, L-Pro-5, D-Asn-6, L-Ser-7 and the unique beta-amino acid-8 present in the iturin family. 1D and 2D NMR, as well as MS ...
Lo Yi-Chen - - 2010
In the field of osteoporosis, there has been growing interest in anabolic agents that enhance bone formation. Here, we examined the effects of betulinic acid on cell proliferation, differentiation, and mineralization of MC3T3-E1 osteoblasts. Then, the impact of betulinic acid on signaling pathways known to be implicated in osteoblastogenesis was ...
Miyase Toshio - - 2010
Three triterpene glycosides and two known ones were isolated from the bark of Albizia procera by using chromatographic techniques. The structures of the compounds were determined to be 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid 16-O-beta-D-glucopyranoside, 3-O-beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid 16-O-beta-D-glucopyranoside and 3-O-alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl echinocystic acid 16-O-beta-D-glucopyranoside. Their structures were determined by NMR techniques including HOHAHA, ...
Lin Shaohui - - 2010
Cationic Pd(II)-catalyzed addition of arylboronic acids to beta,beta-disubstituted enones in high yields was developed. This method provided an efficient method for the construction of quaternary carbon centers, and only 0.5 mol % of Pd(II) catalyst was needed.
Davis Franklin A - - 2010
Cyclic cis-beta-amino Weinreb amides, valuable building blocks for the asymmetric synthesis of cyclic beta-amino acids derivatives, are readily prepared via ring-closing metathesis of sulfinimine-derived N-sulfinyl beta-amino diene Weinreb amides. These unsaturated cyclic cis-beta-amino Weinreb amides are valuable building blocks for the asymmetric synthesis of cyclic beta-amino acid derivatives.
Xiao Yin - - 2010
New single-isomer, cationic beta-cyclodextrins, including mono-6-deoxy-6-pyrrolidine-beta-cyclodextrin chloride (pyCDCl), mono-6-deoxy-6-(N-methyl-pyrrolidine)-beta-cyclodextrin chloride (N-CH(3)-pyCDCl), mono-6-deoxy-6-(N-(2-hydroxyethyl)-pyrrolidine)-beta-cyclodextrin chloride (N-EtOH-pyCDCl), mono-6-deoxy-6-(2-hydroxymethyl-pyrrolidine)-beta-cyclodextrin chloride (2-MeOH-pyCDCl) were synthesized and used as chiral selectors in capillary electrophoresis for the enantioseparation of carboxylic and hydroxycarboxylic acids and dansyl amino acids. The unsubstituted pyCDCl exhibited the greatest resolving ability. Most analytes were ...
Chen Xia - - 2010
Two new triterpenoid saponins (1 and 2) were isolated from the dried aerial parts of Dianthus superbus L. (Caryophyllaceae). Their structures were elucidated on the basis of spectral data to be 3-O-beta-D-glucopyranosyl olean-9(11),12-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (1) and 3-O-beta-D-glucopyranosyl olean-11,13(18)-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (2).
Virtanen S M - - 2010
N-3 (omega-3) fatty acids have been reported to decrease the risk for development of beta-cell autoimmunity and clinical type I diabetes. We set out to examine whether different serum fatty acids are associated with the development of advanced beta-cell autoimmunity in children carrying human leukocyte antigen DQ beta-1 (HLA-DQB1)-conferred susceptibility ...
Sonntag Tessa - - 2010
Sensory-guided fractionation of stewed beef juice using ultrafiltration, gel permeation chromatography, PFPP-HPLC, and HILIC combined with analytical sensory techniques led to the identification of the dipeptides beta-alanyl-N-methyl-L-histidine and beta-alanyl-L-histidine, as well as the creatinine derivatives N-(1-methyl-4-oxoimidazolidin-2-ylidene)aminopropionic acid, N-(1-methyl-4-oxoimidazolidin-2-ylidene)aminoacetic acid, and N-(1-methyl-4-oxoimidazolidin-2-ylidene)amino-4,5,6-trihydroxyhexanoic acid as taste modulators in stewed beef juice. Model ...
Csuk René - - 2010
An endoperoxide was synthesized starting from 11-keto-beta-boswellic acid and screened for antitumor activity in a panel of 15 human cancer cell lines by an SRB assay. The compound induces apoptosis and shows an average IC(50) value of 0.4-4.5 microM.
De Marco Rosaria - - 2010
The methylation reaction of N(beta)-nosyl hydrazides of N-nosyl protected alpha-amino acids by using diazomethane shows a controlled regiochemical trend and makes it possible to obtain the corresponding products methylated at specific positions depending on the amount of diazomethane used. The observed selectivity is closely connected with the different acidity of ...
Yang Pengyuan - - 2010
Intracellular nucleic acid sensors detect microbial RNA and DNA and trigger the production of type I interferon. However, the cytosolic nucleic acid-sensing system remains to be fully identified. Here we show that the cytosolic nucleic acid-binding protein LRRFIP1 contributed to the production of interferon-beta (IFN-beta) induced by vesicular stomatitis virus ...
Joh Eun-Ha - - 2010
A high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method employing electrospray ionization (ESI) has been developed for simultaneous determination of lancemaside A (3-O-beta-D-glucuronopyranosyl-3beta, 16alpha-dihydroxyolean-12-en-28-oic acid 28-O-beta-D-xylopyranosyl(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl ester) and its metabolites in mouse plasma. When lancemaside A (60 mg/kg) was orally administered to mice, echinocystic acid was detected in the blood. ...
Khedr Alaa - - 2010
The aim of the present work is to apply a non-invasive test, using thumb fingerprint residue analysis, for detection of beta-thalassemia (beta-Thal). The relative percentages of free amino acids (AA) in the latent fingerprint of beta-Thal patients and healthy subjects were compared. The sample included 24 beta-Thal patient and 24 ...
Laeger Thomas - - 2010
Although the phenomenon of beta-hydroxybutyric acid (BHBA) impact on satiety and thermogenesis has been described in the past decades, the underlying molecular mechanisms involved remain unresolved. Other metabolites such as glucose, fatty or branched chain amino acids are known to activate the AMP kinase pathway leading to an increase of ...
Wu Min - - 2010
Further chemical investigation of the whole plants of Gentiana loureirii led to the isolation and characterization of three new compounds, cyclic 4-O-beta-D-glucopyranosylcaffeic acid dimer (1), a new alpha-tetralone, 4-hydroxy-6-methyl-alpha-tetralone 4-O-beta-D-glucopyranoside (2), and 3beta,30-dihydroxy-12-ursen-28-oic acid 28-O-beta-D-glucopyranosyl ester (3), along with five known compounds. To the best of our knowledge, compound 1 ...
Pigza Julie A - - 2010
The addition of allyl stannanes to (S)-4,5-dihydro-5-phenyl-2H-oxazinone (3) was achieved under Brønsted acid catalysis to give 2-allylmorpholinones with high diastereoselectivity (up to dr 14.2:1). The product of dimethylallyltributylstannane addition to 3 was converted to l-beta-methylisoleucine, an alpha-amino acid residue found in the complex, biologically active marine-derived peptides polytheonamides A and ...
Ferreira Paula M T - - 2010
Several new beta,beta-dihalo and beta-halo-beta-substituted dehydroalanines and dehydrodipeptides were synthesized by reacting the corresponding dehydroamino acid derivative with a N-halosuccinimide or in the case of beta,beta-di-iododehydroalanines with iodine. The results obtained confirmed that the stereochemical outcome of the halogenation reaction with beta-substituted dehydroamino acids depends on the substrate. Thus, an ...
Marsh Rebekah S - - 2010
beta-Carotene oxygenase 2 cleaves beta-carotene asymmetrically at non-central double bonds of the polyene chain, yielding apocarotenal molecules. The hypothesis tested was that apocarotenoids are able to stimulate transcription by activating retinoic acid receptors (RARs). The effects of long- and short-chain apocarotenals and apocarotenoic acids on the activation of RARalpha and ...
Pauloin Alain - - 2010
Although virtually all cells store neutral lipids as cytoplasmic lipid droplets, mammary epithelial cells have developed a specialized function to secrete them as milk fat globules. We have used the mammary epithelial cell line HC11 to evaluate the potential connections between the lipid and protein synthetic pathways. We show that ...
Cao Hongmei - - 2010
Eleven authenticated botanicals used in the traditional Chinese medicine Huo-Luo-Xiao-Ling Dan were screened for ligands to cyclooxygenase (COX) using pulsed ultrafiltration liquid chromatography-mass spectrometry, and a mass spectrometry-based enzyme assay was used to determine the concentration of each of 17 ligands that inhibited COX-1 or COX-2 by 50% (IC(50)). Acetyl-11-keto-beta-boswellic ...
Weiner Barbara - - 2010
In this critical review, the progress in catalytic asymmetric synthesis of beta-amino acids is discussed, covering the literature since 2002. The review treats transition metal catalysis, organocatalysis and biocatalysis and covers the most important synthetic methods, such as hydrogenation, the Mannich reaction and conjugate additions (160 references).
Tawfik Kamilia A - - 2010
Potent antifungal cyclic lipopeptides, burkholdines (Bk), were isolated from a culture of Burkholderia ambifaria 2.2N. Bk-1229 (1) and Bk-1097 (2) are octapeptides comprised of nonproteinogenic amino acids, including beta-hydroxytyrosine, beta-hydroxyasparagine, and a new fatty acyl amino acid. 1 and 2 are fungicidal against a panel of fungi with potencies 2-60-fold ...
Sharma Gangavaram V M - - 2010
A cyclic tetrapeptide is prepared from alternating (S)-beta-Caa (C-linked carbo-beta-amino acid) and (R)-Ama (alpha-aminoxy acid). Extensive NMR (in CDCl(3) solution) and mass spectral (MS) studies show its halide binding capacity, with a special affinity to the chloride ion. At higher concentration it was found to form molecular aggregates as evidenced ...
Tan Qiang - - 2010
4,7-Dichloro-1-benzothien-2-yl sulfonylaminomethyl boronic acid (DSABA, Compound I) was discovered as the first boronic acid-based class D beta-lactamase inhibitor. It exhibited an IC(50) of 5.6 microM against OXA-40. The compound also inhibited class A and C beta-lactamases with sub to low microM IC(50), and synergized with imipenem against Acinetobacter baumannii.
Hyyryl?inen Anna R M - - 2010
Differentiation of beta-amino acid enantiomers with two chiral centres was investigated by kinetic method with trimeric metal-bound complexes. Four enantiomeric pairs of beta-amino acids were studied: cis-(1R,2S)-, cis-(1S,2R)-, trans-(1R,2R)- and trans-(1S,2S)-2-aminocyclopentanecarboxylic acids (cyclopentane beta-amino acids), and cis-(1R,2S)-, cis-(1S,2R)-, trans-(1R,2R)-, and trans-(1S,2S)-2-aminocyclohexanecarboxylic acids (cyclohexane beta-amino acids). The results showed that the ...
Nishimura Takahiro - - 2010
Rhodium-catalyzed asymmetric 1,4-addition of arylboronic acids to beta-phthaliminoacrylate esters took place efficiently to give high yields of beta-aryl-beta-amino acid esters with 96-99% enantioselectivity, which was realized by use of a hydroxorhodium/chiral diene complex.
Innocenti Alessio A Università degli Studi di Firenze, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, I-50019 Sesto Fiorentino (Firenze), - - 2010
The protein encoded by the NCE103 gene of Candida glabrata, a beta-carbonic anhydrase (CA, EC 4.2.1.1) designated as CgCA, was investigated for its activation with amines and amino acids. CgCA was weakly activated by amino acids such as l-/d-His, l-Phe, l-DOPA, and l-Trp and by histamine or dopamine (K(A)s of ...
Kim Hyun Jung - - 2010
The impact of beta-glucan molecular weight (MW) on in vitro bile-acid binding and in vitro fermentation with human fecal flora was evaluated. beta-Glucan extracted from oat line 'N979-5-4' was treated with lichenase (1,3-1,4-beta-D-glucanase) to yield high (6.87x10(5) g/mol), medium (3.71x10(5) g/mol), and low (1.56x10(5) g/mol) MW fractions. The low MW ...
Ma Chunming - - 2010
The beta-carboline alkaloids have been characterized as a class of potential antitumor agents. To further enhance the cytotoxic potency and improve water solubility of beta-carboline, a series of new beta-carboline amino acid ester, beta-carboline amino acid and N(2)-benzylated quaternary beta-carboline amino acid ester conjugates were designed and synthesized, and the ...
Hamed Refaat B - - 2010
The utility of wild-type and variant carboxymethylproline synthases for biocatalysis was demonstrated by preparing functionalised 5-, 6- and 7-membered N-heterocycles from amino acid aldehydes and (alkylated) malonyl-coenzyme A derivatives; the N-heterocycles produced were converted to the corresponding bicyclic beta-lactams by a carbapenem synthetase.
Lobo Glenn P - - 2010
The uptake of dietary lipids from the small intestine is a complex process that depends on the activities of specific membrane receptors with yet unknown regulatory mechanisms. Using both mouse models and human cell lines, we show here that intestinal lipid absorption by the scavenger receptor class B type 1 ...
Akihisa Toshihiro - - 2010
A new iridoid glycoside, 9-epi-6alpha-methoxy geniposidic acid (4), three new hemiterpene glycosides, 3-methylbut-3-enyl 2'-O-(beta-D-glucopyranosyl)-beta-D-glucopyranoside (nonioside K) (6), 3-methylbut-3-enyl 6'-O-(beta-D-xylopyranosyl)-beta-D-glucopyranoside (nonioside L) (8), and 3-methylbut-3-enyl 6'-O-(beta-D-xylofuranosyl)-beta-D-glucopyranoside (nonioside M) (9), and two new saccharide fatty acid esters, 6'-O-(beta-D-glucopyranosyl)-1'-O-[(2xi)-2-methylbutanoyl]-beta-D-glucopyranose (nonioside N) (16) and 6'-O-(beta-D-xylopyranosyl)-1'-O-[(2xi)-2-methylbutanoyl]-beta-D-glucopyranose (nonioside O) (17), were isolated from a methanol extract ...
Sameermahmood Zaheer - - 2010
Gallic acid is claimed to possess antioxidant, antiinflammatory and cytoprotective effects. Since pancreatic islets from Type 2 diabetic patients have functional defects, it was hypothesized that glucolipotoxicity might induce apoptosis in beta-cells and gallic acid could offer protection. To test this, RINm5F beta-cells were exposed to high glucose (25 microM) ...
Karch Florian - - 2010
Glycopeptides from the mucin family decorated with tumour-associated carbohydrate antigens (TACA) have proven to be important target structures for the development of molecularly defined anti-cancer vaccines. The strategic incorporation of β-amino acid building blocks into such mucin-type sequences offers the potential to create pseudo-glycopeptide antigens with improved bioavailability for tumour ...
Bhattacharjee Nicholus - - 2010
Despite the importance of β-strands as main building blocks in proteins, the propensity of amino acid in β-strands is not well-understood as it has been more difficult to determine experimentally compared to α-helices. Recent studies have shown that most of the amino acids have significantly high or low propensity towards ...
Tasn?di G?bor - - 2010
The enantioselective (E approximately 200) Burkholderia cepacia-catalysed hydrolyses of beta-amino esters with H(2)O (0.5 equiv.) in t-BuOMe or in i-Pr(2)O at 45 degrees C are described. The enantiomers of biologically relevant beta-arylalkyl-substituted beta-amino acids, and especially (R)-3-amino-3-(2,4,5-trifluorophenyl)butanoic acid, the intermediate of the new antidiabetic drug sitagliptine, were prepared with high ...
Szymanski Wiktor - - 2009
An approach is described for the synthesis of aromatic alpha- and beta-amino acids that uses phenylalanine aminomutase to catalyze a highly enantioselective addition of ammonia to substituted cinnamic acids. The reaction has a broad scope and yields substituted alpha- and beta-phenylalanines with excellent enantiomeric excess. The regioselectivity of the conversion ...
Verkuijl Bastiaan J V - - 2010
An efficient and selective method for the extraction of alpha-amino acids in preference over their beta-isomers using PdCl(2)(PPh(3))(2) was discovered, which enables the separation of product mixtures obtained in the enantioselective enzymatic formation of beta-amino acids.
Bisio Angela - - 2009
A study has been carried out on the surface exudate of Salvia x jamensis, which showed a significant phytotoxic activity against Papaver rhoeas L. and Avena sativa L.. Bioguided separation of the exudate yielded active fractions from which 3 beta-hydroxy-isopimaric acid (1), hautriwaic acid (2), betulinic acid (3), 7,8 beta-dihydrosalviacoccin ...
Fryszkowska Anna - - 2010
A short chemoenzymatic synthesis of beta-aryl-gamma-aminobutyric acids has been developed, based on a highly enantioselective biocatalytic reduction of beta-aryl-beta-cyano-alpha,beta-unsaturated carboxylic acids.
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