Articles from Wiley
Rapid Redox Processes of <i>c</i>-Type Cytochromes in A Living Cell Suspension of <i>Shewanella oneidensis</i> MR-1
This study provides a direct molecular level observation of the in vivo rapid EET processes under non-invasive physiological conditions by employing a UV/Vis optical-fibre spectrometer with an integrated-sphere detector. The rapid reaction kinetics and thermodynamics were analysed in four stages according to the step-by-step elementary electro transfer reactions. A suitable and powerful approach was established to examine the extents and rates of biological events in situ without disrupting the complexity of the live cellular environments.
Tongxu Liu, Yundang Wu, Fangbai Li, Xiaomin Li, Xiaobo Luo
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201602021. Read article
Calixarene-Based <i>n</i>-Dialkylamino Extractants for Selective Platinum Group Metal Separation from Automotive Catalysts
Calixarene-Based Extractants for PGM separation from automotive catalysts’ leach liquors: Three calixarene-based n-dialkylamino extractants have been synthesized. The extractants exhibit selective extraction of valuable platinum group metals (PGMs), specifically Pd(II) and Pt(IV), from leach liquors of automotive catalysts. Stripping of Pd(II) and Pt(IV) from organic solutions and reusability of the extractants were achieved.
Manabu Yamada, Muniyappan Rajiv Gandhi, Yu Kaneta, Yetian Hu, Atsushi Shibayama
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601981. Read article
This study shows that observation of fluorescence oscillation is a clear signature of constitutive enzymatic activity of NM-II−C2 which exists in extended 6S form when the entire length of C2 insert is present.
Shyamtanu Chattoraj, Shekhar Saha, Debdatta Halder, Siddhartha S. Jana, Kankan Bhattacharyya
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601963. Read article
Synthesis of a Safranin T - <i>p</i>-Sulfonatocalixarene Complex by Means of Supramolecular Complexation
A stable supramolecular complex is synthesied using facile supramolecular complexation using p-sulfonatocalixarene and cationic safranin T dye molecule. Using spectral, electrochemical, FT-IR and 2D NMR techniques, the complex was successfully studied both solid and solution medium.
Bosco Maria Ashwin, Arumugam Vinothini, Thambusamy Stalin, Paulpandian Muthu Mareeswaran
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601939. Read article
Concise Synthesis of a Pentasaccharide Repeating Unit Corresponding to the <i>O</i>-Antigen of <i>Salmonella Enterica</i> O51
Stereoselective glycosylation of suitably protected monosaccharide intermediates furnished a pentasaccharide linked to an aminoethyl linker corresponding to the cell wall O-antigen of S. enterica O51, which is responsible for several outbreaks of foodborne illness. Stereoselective glycosylation and removal of p-methoxybenzyl protecting group was carried out in a one-pot reaction condition.
Ishani Bhaumik, Anup Kumar Misra
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601918. Read article
Two steps in one-pot: dehydration of sorbitol and esterification of isosorbide can be carried out with the same heterogeneous catalyst, in the absence of solvent, under mild conditions in one-pot. Isosorbide diacetate is obtained with the same yield as in the two individual steps, but esterification with octanoic acid is sensitive to the presence of water on the catalyst.
José M. Fraile, Carlos J. Saavedra
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601866. Read article
An Efficient and Metal–free Synthesis of α-Ketoesters <i>via</i> Oxidative Cross Coupling of Arylglyoxals with Alcohols
In this work, we have described a simple and convenient method for the synthesis of α-ketoesters through oxidative cross coupling of arylglyoxals with alcohols by using N-bromosuccinimide (NBS) as an oxidant and 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) as a base at room temperature. The salient features of this method are mild reaction conditions, broad substrate scope and short reaction time. This various functional group compatible approach provides an easy access to α-ketoesters in good to excellent yield.
Kamlesh S. Vadagaonkar, Hanuman P. Kalmode, Suresh L. Shinde, Atul C. Chaskar
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601825. Read article
Transient Catalytic Activity of a Triazole-based Gelator Regulated by Molecular Gel Assembly/Disassembly
Transient catalysis. A dynamic catalytic system is described in which an amphiphilic gelator functionalized with an azidocoumarine triazole fragment shows a transient self-assembly/disassembly behaviour regulated by the presence of the reactants. The system shows temporary catalytic activity towards a model ‘click’ reaction that vanishes upon consumption of the reagents and reappearance of a gel phase.
Marco Araújo, Beatriu Escuder
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601816. Read article
Enyne compounds are useful building blocks to construct various cyclic skeletons. An efficient synthetic pathway to enyne derivatives from readily available allenols has been accomplished in the presence of sodium hydride and trimethyl phosphate as an inexpensive and stable activator of hydroxy groups of allenols. The present method could be applied to various allenol derivatives to give a variety of functionalized-enyne products.
Shota Asai, Maho Kato, Yasunari Monguchi, Hironao Sajiki, Yoshinari Sawama
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601789. Read article
The copper(II) complexes of 1,4 diazepane based ligands have been synthesized as models for copper amine oxidases (CAOs). The molecular structure of complexes adopts distorted square pyramidal geometry as identical to native CAOs enzyme. The Cu-N(2.0 Å) bond distances of model complexes are similar to the Cu-NHis bond distances in the CAOs enzyme (1.9-2.2 Å).The model substrate 2-aminophenol is simultaneously converted into o-quinone via oxidative deamination by model complexes using O2 in water. The secondary coordination sphere of CAOs is duplicated by an additional pyridine arm in complexes, which is decoordinated from the copper center and act as an acid-base catalyst as like in CAO catalysis.
Sethuraman Muthuramalingam, Shanmugam Subramaniyan, Themmila Khamrang, Marappan Velusamy, Ramasamy Mayilmurugan
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601786. Read article
Copper-Catalyzed Recyclable Synthesis of (<i>Z</i>)-3-Alkylideneisoindolinones by Cycloisomerization of 2-Alkynylbenzamides in Ionic Liquids
The first example of the synthesis of (Z)-3-alkylideneisoindolinones by cycloisomerization of 2-alkynylbenzamides in ionic liquids is reported. Under the promotion by CuCl2 as simple and inexpensive catalyst, in the presence of K2CO3 as base, and in 1-ethyl-3-methylimidazolium ethyl sulfate (EmimEtSO4) as the solvent, a series of (Z)-3-alkylideneisoindolinones were chemo-, regio-, and stereoselectively obtained in high yields, and the catalyst/solvent/base system could be recycled several times without appreciable loss of activity. DFT calculations confirmed the roles exerted by the base and CuCl2 in favoring the anti-5-exo-dig reaction course leading to (Z)-3-alkylideneisoindolinones.
Raffaella Mancuso, Christian S. Pomelli, Dnyaneshwar S. Raut, Nadia Marino, Salvatore V. Giofrè, Roberto Romeo, Stefania Sartini, Cinzia Chiappe, Bartolo Gabriele
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601738. Read article
Scalable Synthesis and Supramolecular Assembly of <i>trans</i>-A<sub>2</sub>B<sub>2</sub> Porphyrins with Pendant Carboxylic Functional Groups
Facile synthetic methodology of a novel class of meso-related trans-A2B2 porphyrin building units (A=COOH), allows to introduce diverse ′B′ molecular-recognition groups on the porphyrin scaffolds to affect their supramolecular self-assembly in crystals.
Bharat Kumar Tripuramallu, Ramesh Palakuri, Hatem M. Titi, Israel Goldberg
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601716. Read article
Ag(I)-Catalyzed Cyclizative Hydration of Alkynes and Propargylic Alcohols. A Mild Approach to 2-Acylfuran Derivatives
A mild strategy for the synthesis of 2-acylfuran derivatives via cyclizative hydration of propargylic alcohols and alkynes, under Ag(I) catalysis has been reported. This is the first report employing the propargylic alcohols and their derivatives as alkyne partners in the cyclizative hydration process.
Soniya Gandhi, Prabhakararao Tharra, Beeraiah Baire
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601623. Read article
Aerobic Water–based Oxidation of 2,3,6-Trimethylphenol to Trimethyl-1,4-benzoquinone over Copper(II) Nitrate Catalyst
An efficient method for aerobic oxidation of 2,3,6-trimethylphenol to trimethyl-1,4-benzoquinone catalyzed by copper(II) nitrate is developed in water. Almost complete conversion of 2,3,6-trimethylphenol was achieved and the yield for trimethyl-1,4-benzoquinone reached 94 % under mild conditions. Based on the results, a reaction mechanism involving free radical pathway is proposed. This study offers a safe system for aerobic oxidation of 2,3,6-trimethylphenol to trimethyl-1,4-benzoquinone with high activity and selectivity under halogen ions-free conditions.
M. S. Liangning Hu, Jianqiang Yu, Hongchuan Xin, Zengjian An, Wenshou Sun
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601606. Read article
Incorporating Pd(OAc)<sub>2</sub> on Imine Functionalized Microporous Covalent Organic Frameworks: A Stable and Efficient Heterogeneous Catalyst for Suzuki-Miyaura Coupling in Aqueous Medium
We reported the reusable Pd/TATAE catalyst and their catalytic efficiencies is measured by the Suzuki-Miyaura coupling reaction in an environmentally benign aqueous medium at room temperature with very good yield.
Velu Sadhasivam, Rajendiran Balasaravanan, Chinnadurai Chithiraikumar, Ayyanar Siva
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601440. Read article
Chemical Synthesis of L-Fucose Derivatives for Acceptor Specificity Characterisation of Plant Cell Wall Glycosyltransferases
Seven derivatives of L-fucose were chemically synthesized and characterized. The derivatives of L-fucose were designed to mimic the L-fucose moieties present in the A-chain of pectic rhamnogalacturonan-II and used to investigate the regiospecificity of three heterologously expressed xylosyltransferases from Arabidopsis thaliana. The monosaccharide methyl α-L-fucopyranoside was the most efficient acceptor, 30 fold more effective than methyl 4-O-methyl-α-L-fucopyranoside. O-methylation in position 2 or 3 abolished acceptor function.
Iben Damager, Carl Erik Olsen, Jack Egelund, Bodil Jørgensen, Bent Larsen Petersen, Peter Ulvskov, Birger Lindberg Møller, Mohammed Saddik Motawia
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601315. Read article
Ultrasensitive Fluorescent Biosensor for Creatinine Determination in Human Biofluids Based on Water Soluble Rhodamine B Dye-Au<sup>3+</sup> ions Conjugate
A very simple and highly selective, colorimetric as well as fluorescence biosensor platform was designed for creatinine biomolecule by utilizing water soluble Rhodamine B dye along with Au3+ ions within the linear range of 10 nM to 1.2 x 10−3 M along with the limit of detection of 5 nM. The total response time is found to be 15 minutes only and we have successfully extended this application for the determination of creatinine in human urine samples.
S. Ellairaja, K. Shenbagavalli, V. S. Vasantha
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601110. Read article
Carbon space explored: For a thorough analysis of complex systems by mass spectrometry peak instrument performance in all aspects is needed. A new approach is presented here, that combines peak sensitivity with excellent resolving power. Thus a major part of the compositional space populated by carbon species can be explored.
Alessandro Vetere, Wolfgang Schrader
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601083. Read article
Synthesis of a silyl derivative of revised aglycone of marine anticancer macrolide Mandelalide A is described. The synthetic highlights include acid-catalyzed epoxide opening, Chelation controlled Grignard reaction, Still-Gennari olefination, Pd-catalyzed intramolecular alkoxycarbonylation, Kocien′ski-Julia olefination and Shiina macrolactonization as key steps
Praveen AnkiReddy, Sandeep AnkiReddy, Gowravaram Sabitha
ChemistrySelect, January 24, 2017, DOI: 10.1002/slct.201601076. Read article
Unsymmetrical Bipyrrole-Derived β-Tetraalkylporphycenes and C–H···Br–C Interaction Induced 2D Arrays of the 2:1 Supramolecular Sandwich Complex of Their <i>cis</i>-/<i>trans</i>-Dibromo Isomers
Two hybrid β-tetraalkyl-substituted porphycenes, including the unsymmetrical cis isomer with interesting photophysical properties, are synthesized. The selectively synthesized dibromo derivatives of their mixture forms a strong π–π stacked supramolecular sandwich complex that extends into a 2D array only through C–H···Br–C interactions.
Narendra N. Pati, B. Sathish Kumar, Brijesh Chandra, Pradeepta K. Panda
Eur. J. Org. Chem., January 24, 2017, DOI: 10.1002/ejoc.201601584. Read article