Development of a new protein labeling strategy, oxidation labeling. part 1: Preliminary evaluation and synthesis of tautomycin containing a metal coordinating unit

March 9th, 2010

In the current work we present our preliminary evaluation of a new protein labeling strategy, namely oxidation labeling. We found that a bis(2-picolyl) amine analogue coordinating Cu+ was able to oxidize histidine to oxo-histedine in a small peptide by generating reactive oxygen species upon exposure to hydrogen peroxide. The bis(2-picolyl) amine unit was then incorporated into the natural product tautomycin via an oxime linker. The compound, which showed good activity toward protein phosphatase 1γ (PP1γ), will be used in oxidation labeling studies with PP1γ.

http://dx.doi.org/10.1016/j.tet.2009.12.036
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Boron–dipyrromethene based specific chemodosimeter for fluoride ion

March 9th, 2010

3,5-Bis(trimethylsilylethynyl)-4,4-difluoro-8-(4-tolyl)-4-bora-3a,4a-diaza-s-indacene [BODIPY(CCTMS)2] has been synthesized by coupling of 3,5-dibromo-4,4-difluoro-8-(4-tolyl)-4-bora-3a,4a-diaza-s-indacene with trimethylsilylacetylene under pd(0) coupling conditions. The BODIPY(CCTMS)2 was used as a selective colourimetric and fluorescent chemodosimeter for fluoride ion, following the F ion induced cleavage of trimethylsilyl group, the protecting group of ethyne functionality by monitoring the changes in UV–vis and fluorescence properties. The dosimeter BODIPY(CCTMS)2 display clear changes in colour, absorption and emission bands selectively for F ion over other anions such as Cl, Br, I, ClO4 and HPO42−.

http://dx.doi.org/10.1016/j.tet.2009.12.039
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Anion recognition through hydrogen bonding by adamantane-dipyrromethane receptors

March 9th, 2010

Adamantane-dipyrromethane (AdD) receptors [di(pyrrole-2-yl)methyladamantane (1), 2,2-di(pyrrole-2-yl)adamantane (2), 1,3-bis[di(pyrrole-2-yl)methyl]adamantane (3), 2,2,6,6-tetra(pyrrole-2-yl)adamantane (4)] form complexes with F, Cl, Br, AcO, NO3, HSO4, and H2PO4. The association constants of the complexes were determined by 1H NMR titrations, whereas the geometries of complexes 1·F (2:1), 2·F (2:1), 2·Cl (2:1), 2·AcO (2:1), and 4·F (1:1) were determined by X-ray structural analysis. The most stable complexes are of 2:1 stoichiometry with F and AcO. The stability constants are in accordance with the anion basicity and the ability of AdD receptors to place the hydrogen bonding donor groups in a tetrahedral fashion around anions. The binding energies of the complexes between receptors 14 and F anion are calculated using quantum chemical methods. The calculated results show that the solvent polarity is important for the complexation of fluoride ion with AdD receptors 14.

http://dx.doi.org/10.1016/j.tet.2010.01.018
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Ratiometric fluorescent and colorimetric sensors for Cu2+ based on 4,5-disubstituted-1,8-naphthalimide and sensing cyanide via Cu2+ displacement approach

March 9th, 2010

Two 4,5-disubstituted-1,8-naphthalimide derivatives 1 and 2 were synthesized as ratiometric fluorescent and colorimetric sensors for Cu2+, respectively. In 100% aqueous solutions of 1, the presence of Cu2+ induces a strong and increasing fluorescent emission centered at 478 nm at the expense of the fluorescent emission of 1 centered at 534 nm. Compound 2 senses Cu2+ by means of a colorimetric (primrose yellow to pink) method with a thorough quench in emission attributed to the deprotonation of the secondary amine conjugated to the naphthalimide fluorophore. 1-Cu2+ and 2-Cu2+ sense cyanide in ratiometric way via colorimetric and fluorescent changes.

http://dx.doi.org/10.1016/j.tet.2010.01.008
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Synthesis of reversible fluorescent organogel containing 2-(2′-hydroxyphenyl)benzoxazole: fluorescence enhancement upon gelation and detecting property for nerve gas simulant

March 9th, 2010

A new low molecular mass organogelator 1 containing 2-(2′-hydroxyphenyl)benzoxazole (HPB) group with long alkyl chain was synthesized by the reaction with 5-amino-2-(2′-hydroxy-4′-methylphenyl)benzoxazole and dodecyl isocyanate in THF at room temperature. The reversible gelation ability of 1 was investigated using a heating-cooling method in various organic solvents. The stable organogel was formed from carbon tetrachloride or from cyclohexane at the concentration as low as 0.9%. The self-assembled supramolecular gel structure formed by non-covalent bonding was confirmed with field emission-scanning electron microscope (FE-SEM) exhibiting fibril- or ribbon-shaped structure depending on the solvent used. Regarding the aggregation-induced emission enhancement (AIEE) phenomenon, the optical properties were investigated in its solution and gelled state. The detecting properties of resulting organogel toward nerve gas simulant were monitored by UV–vis and fluorescence spectroscopy. Both color change from colorless to greenish yellow and disruption of gel structure resulting from alteration in intermolecular forces were observed upon the exposure to nerve gas simulant.

http://dx.doi.org/10.1016/j.tet.2010.01.006
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Supramolecular gelation of alcohol and water by synthetic amphiphilic gallic acid derivatives

March 9th, 2010

The supramolecular organogelation of alcohols was observed in relatively hydrophobic amphiphiles with a short oligo(ethylene glycol) unit and three long alkyl chains at room temperature, while the hydrogelation occurred in more hydrophilic gelators with a longer poly(ethylene glycol) unit and two long alkyl chains at various temperatures. When a hot aqueous solution of some of the synthetic hydrogelators was cooled down, the supramolecular hydrogel was formed at room temperature. In some other amphiphiles with less intermolecular interactivity in water at room temperature, a reverse phase transition of sol to gel was observed by elevating the temperature of their aqueous systems, especially below a physiological temperature, 37 °C. The supramolecular hydrogelation at a low or high temperature was dependent on a slight molecular modification of the synthetic amphiphiles.

http://dx.doi.org/10.1016/j.tet.2010.01.002
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Total Synthesis of Coralloidolides A, B, C, and E

March 9th, 2010
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Total Synthesis of Lipoteichoic Acid of Streptococcus pneumoniae

March 9th, 2010
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Supramolecular Interactions at the Inorganic-Organic Interface in Hybrid Nanomaterials

March 9th, 2010
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High-Generation Second-Order Nonlinear Optical (NLO) Dendrimers: Convenient Synthesis by Click Chemistry and the Increasing Trend of NLO Effects

March 9th, 2010
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Nitrogen-Doped Ordered Mesoporous Graphitic Arrays with High Electrocatalytic Activity for Oxygen Reduction

March 9th, 2010
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Diastereo- and Enantioselective Catalytic Tandem Michael Addition/Mannich Reaction: Access to Chiral Isoindolinones and Azetidines with Multiple Stereocenters

March 9th, 2010
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Bambus[6]uril

March 9th, 2010
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Ethanolysis of N-substituted norbornane epoxyimides: Discovery of diverse pathways depending on substituent’s character

March 9th, 2010

Tetyana Petrova, Igor Tarabara, Vitaliy Palchikov, Liliya Kasyan, Dmytro Kosenkov, Sergiy Okovytyy, Leonid Gorb, Svetlana Shishkina, Oleg Shishkin, Jerzy Leszczynski
(Paper from Org. Biomol. Chem.)
Tetyana Petrova, Org. Biomol. Chem., 2010, DOI: 10.1039/b917850c
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The Fluid-Mosaic Model, Homeoviscous Adaptation, and Ionic Liquids: Dramatic Lowering of the Melting Point by Side-Chain Unsaturation

March 8th, 2010
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Detection of Single Enzyme Molecules inside Nanopores on the Basis of Chemiluminescence

March 8th, 2010
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Amide-to-Ester Substitution Allows Fine-Tuning of the Cyclopeptide Conformational Ensemble

March 8th, 2010
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General and Efficient Copper-Catalyzed Three-Component Coupling Reaction towards Imidazoheterocycles: One-Pot Synthesis of Alpidem and Zolpidem

March 8th, 2010
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Physical Chemistry: Prize for S. Schlücker Popular Chemistry: G. Schwedt Awarded Young Talent Prizes of the ADUC

March 8th, 2010
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Organocatalytic asymmetric synthesis of polyfunctionalized 3-(cyclohexenylmethyl)-indoles via a quadruple domino Friedel-Crafts-type/Michael/Michael/aldol condensation reaction

March 8th, 2010

Dieter Enders, Chuan Wang, Meruyert Mukanova, Andreas Greb
(Communication from Chem. Commun.)
Dieter Enders, Chem. Commun., 2010, DOI: 10.1039/c002839h
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New chiral ligands bearing two N-heterocyclic carbene moieties at a dioxolane backbone. Gold, palladium and rhodium complexes as enantioselective catalysts

March 8th, 2010

Avelina Arnanz, Camino Gonzalez-Arellano, Alberto Juan, Gonzalo Villaverde, Avelino Corma, Marta Iglesias, Felix Sanchez
(Communication from Chem. Commun.)
Avelina Arnanz, Chem. Commun., 2010, DOI: 10.1039/b922534j
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Design, synthesis, and complementary recognition of [small beta]-hairpin peptides stabilized by artificial DNA base-pairing amino acids

March 8th, 2010

Katsuhiro Isozaki, Kazushi Miki
(Communication from Chem. Commun.)
Katsuhiro Isozaki, Chem. Commun., 2010, DOI: 10.1039/b924239b
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Rapid access to 1-methyleneindenes via palladium-catalyzed tandem reactions of 1-(2,2-dibromovinyl)-2-alkynylbenzenes with arylboronic acids

March 8th, 2010

Shengqing Ye, Xiaodi Yang, Jie Wu
(Communication from Chem. Commun.)
Shengqing Ye, Chem. Commun., 2010, DOI: 10.1039/b926763h
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Synthesis and molecular properties of donor-[small pi]-spacer-acceptor ynamides with up to four conjugated alkyne units

March 8th, 2010

Bernhard Witulski, Torsten Schweikert, Dieter Schollmeyer, Nicolai A. Nemkovich
(Communication from Chem. Commun.)
Bernhard Witulski, Chem. Commun., 2010, DOI: 10.1039/b919275a
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Computational enzymology

March 8th, 2010

Richard Lonsdale, Kara E. Ranaghan, Adrian J. Mulholland
(Feature Article from Chem. Commun.)
Richard Lonsdale, Chem. Commun., 2010, DOI: 10.1039/b925647d
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Evidence of drug confinement into silica mesoporous matrices by STEM spherical aberration corrected microscopy

March 8th, 2010

Maria Vallet-Regi, Miguel Manzano, Jose M. Gonzalez-Calbet, Eiji Okunishi
(Communication from Chem. Commun.)
Maria Vallet-Regi, Chem. Commun., 2010, DOI: 10.1039/c000806k
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Using the Wittig reaction to produce alkenylcarbaboranes

March 8th, 2010

Antonio Sousa-Pedrares, Clara Vinas, Francesc Teixidor
(Communication from Chem. Commun.)
Antonio Sousa-Pedrares, Chem. Commun., 2010, DOI: 10.1039/b921122e
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Synthesis of a chiral artificial receptor with catalytic activity in Michael additions and its chiral resolution by a new methodology

March 8th, 2010

Luis Simon, Francisco M. Muniz, Angel Fuentes de Arriba, Victoria Alcazar, Cesar Raposo, Joaquin R. Moran
(Communication from Org. Biomol. Chem.)
Luis Simon, Org. Biomol. Chem., 2010, DOI: 10.1039/b925367j
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A comparative study of the self-immolation of para-aminobenzylalcohol and hemithioaminal-based linkers in the context of protease-sensitive fluorogenic probes

March 8th, 2010

Yves Meyer, Jean-Alexandre Richard, Bruno Delest, Pauline Noack, Pierre-Yves Renard, Anthony Romieu
(Communication from Org. Biomol. Chem.)
Yves Meyer, Org. Biomol. Chem., 2010, DOI: 10.1039/b926316k
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Hierarchical films of layered double hydroxides by using a sol-gel process and their high adaptability in water treatment

March 6th, 2010

Yufei Zhao, Shan He, Min Wei, David G. Evans, Xue Duan
(Communication from Chem. Commun.)
Yufei Zhao, Chem. Commun., 2010, DOI: 10.1039/b926906a
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