Angewandte Chemie International Edition

Cover image for Vol. 53 Issue 30

Editor: Peter Gölitz, Deputy Editors: Neville Compton, Haymo Ross

Online ISSN: 1521-3773

Associated Title(s): Angewandte Chemie, Chemistry - A European Journal, Chemistry – An Asian Journal, Zeitschrift für Chemie

Upcoming Hot Papers

Hot Papers are chosen by the Editors for their importance in a rapidly evolving field of high current interest. Many of the "Very Important Papers" (VIPs) would certainly qualify to be included here, but such a duplication is avoided.

Peptide Antivirals

Cell-Penetrating, Dimeric α-Helical Peptides: Nanomolar Inhibitors of HIV-1 Transcription

Sangmok Jang, Dr. Soonsil Hyun, Seoyeon Kim, Seonju Lee, Prof. Dr. Im-Soon Lee, Prof. Dr. Masanori Baba, Prof. Dr. Yan Lee and Prof. Dr. Jaehoon Yu

Cell-Penetrating, Dimeric α-Helical Peptides: Nanomolar Inhibitors of HIV-1 TranscriptionGoing viral: Nearly quantitative penetration into eukaryotic cells and effective inhibition of the elongation of the short hairpin RNA transcript TAR at low nanomolar concentrations has been achieved by using dimeric α-helical peptide bundles based on leucine (L) and lysine (K). The effective inhibition of HIV-1 replication strongly suggests that these dimers have strong potential as anti-HIV-1 drugs.

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Protein Dynamics

Local Transient Unfolding of Native State PAI-1 Associated with Serpin Metastability

Dr. Morten B. Trelle, Dr. Jeppe B. Madsen, Prof. Peter A. Andreasen and Prof. Dr. Thomas J. D. Jørgensen

Local Transient Unfolding of Native State PAI-1 Associated with Serpin MetastabilitySerpin proteins are prone to pathological conformational change, for instance by conversion to an inactive, so-called latent form. Using advanced hydrogen/deuterium-exchange mass spectrometry transient unfolding of a serpin is shown under native condition. Based on these observations, a new mechanism (see picture) is proposed.

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Perovskite Solar Cells

A Fast Deposition-Crystallization Procedure for Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells

Manda Xiao, Dr. Fuzhi Huang, Wenchao Huang, Yasmina Dkhissi, Dr. Ye Zhu, Prof. Dr. Joanne Etheridge, Dr. Angus Gray-Weale, Prof. Dr. Udo Bach, Prof. Dr. Yi-Bing Cheng and Prof. Dr. Leone Spiccia

A Fast Deposition-Crystallization Procedure for Highly Efficient Lead Iodide Perovskite Thin-Film Solar CellsFast and thin: Flat, uniform thin films of CH3NH3PbI3 perovskites have been produced by a fast, one-step procedure involving spin-coating of a DMF solution of CH3NH3PbI3 and immediate exposure to chlorobenzene to induce crystallization. Planar heterojunction solar cells made with these films gave a maximum power conversion efficiency of 16.2 %.

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Biocatalysis

Unprecedented Role of Hydronaphthoquinone Tautomers in Biosynthesis

Dr. Syed Masood Husain, Dr. Michael A. Schätzle, Dr. Steffen Lüdeke and Prof. Dr. Michael Müller

Unprecedented Role of Hydronaphthoquinone Tautomers in BiosynthesisBreaking the cycle: In studies on the reduction of 2-hydroxynaphthoquinones to the stable 1,4-diketo tautomeric form of hydronaphthoquinones and their further reduction by fungal tetrahydroxynaphthalene reductase, diketo tautomers emerge as true intermediates in biosynthesis. Their formation breaks the (redox) cycle, thus protecting the cell from stress-related redox events.

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Membrane Preparation

Coordination-Driven In Situ Self-Assembly Strategy for the Preparation of Metal–Organic-Framework Hybrid Membranes

Rong Zhang, Prof. Shulan Ji, Dr. Naixin Wang, Lin Wang, Prof. Guojun Zhang and Jian-Rong Li

Coordination-Driven In Situ Self-Assembly Strategy for the Preparation of Metal–Organic-Framework Hybrid MembranesMopping up the mess: A hybrid membrane composed of the metal–organic framework (MOF) ZIF-8 and poly(sodium 4-styrenesulfonate) was prepared by coordination-driven in situ self-assembly method. The MOF particles were well-dispersed in the polymer in the resulting stable membrane (see picture), which showed excellent performance in the nanofiltration and separation of dyes from water.

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Selective CO2 Capture in ZIFs

Selective Capture of Carbon Dioxide under Humid Conditions by Hydrophobic Chabazite-Type Zeolitic Imidazolate Frameworks

Nhung T. T. Nguyen, Dr. Hiroyasu Furukawa, Dr. Felipe Gándara, Dr. Hoang T. Nguyen, Kyle E. Cordova and Prof. Omar M. Yaghi

Selective Capture of Carbon Dioxide under Humid Conditions by Hydrophobic Chabazite-Type Zeolitic Imidazolate FrameworksWetting their appetite for CO2: Hydrophobic zeolitic imidazolate frameworks (ZIFs) with the chabazite (CHA) topology selectively capture CO2 from N2 in the presence of water. They thus overcome crucial challenges faced by many other porous materials for which even the smallest amount of water causes decomposition or decreases the materials’ ability to capture CO2.

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Nitrogen Photofixation

Plasmon-Induced Ammonia Synthesis through Nitrogen Photofixation with Visible Light Irradiation

Dr. Tomoya Oshikiri, Prof. Kosei Ueno and Prof. Hiroaki Misawa

Plasmon-Induced Ammonia Synthesis through Nitrogen Photofixation with Visible Light IrradiationSee the light of day: A plasmon-induced ammonia synthesis technique that responds to visible light and is based on a strontium titanate (SrTiO3) photoelectrode loaded with gold nanoparticles has been developed. It is deduced that plasmon-induced charge separation at the Au/SrTiO3 interface promotes oxidation in the anodic chamber and subsequent nitrogen reduction on the cathodic side.

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One-Pot Synthesis of Highly Substituted Polyheteroaromatic Compounds by Rhodium(III)-Catalyzed Multiple C[BOND]H Activation and Annulation

Jayachandran Jayakumar, Dr. Kanniyappan Parthasarathy, Yi-Hsiang Chen, Tai-Hua Lee, Prof. Dr. Shih-Ching Chuang and Prof. Dr. Chien-Hong Cheng

One-Pot Synthesis of Highly Substituted Polyheteroaromatic Compounds by Rhodium(III)-Catalyzed Multiple C<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />H Activation and AnnulationActivated and annulated: A rhodium-catalyzed one-pot synthesis of highly substituted polyheteroaromatic compounds from N-hydroxybenzamidines and alkynes is described. This reaction likely proceeds through multiple C[BOND]H bond activation and annulation.

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Perovskite Solar Cells

High-Performance Hole-Extraction Layer of Sol–Gel-Processed NiO Nanocrystals for Inverted Planar Perovskite Solar Cells

Zonglong Zhu, Yang Bai, Teng Zhang, Dr. Zhike Liu, Dr. Xia Long, Zhanhua Wei, Zilong Wang, Lixia Zhang, Prof. Jiannong Wang, Prof. Feng Yan and Prof. Shihe Yang

High-Performance Hole-Extraction Layer of Sol–Gel-Processed NiO Nanocrystals for Inverted Planar Perovskite Solar CellsThe advantages are crystal clear: A transparent layer of NiO nanocrystals fabricated by a simple sol–gel processing method acted as an efficient hole-transport layer in an inverted perovskite solar cell. With the NiO film (see picture), a cell efficiency of 9.11 % was observed: by far the highest for a planar perovskite solar cell based on an inorganic hole-extraction layer.

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Asymmetric Synthesis

Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation Reactions

Zhiyong Yu, Robert J. Ely and Prof. James P. Morken

Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation ReactionsBorylation-based synthesis: The development of a strategy for stereocontrol in catalytic diene hydroboration enables the synthesis of a critical building block for the assembly of (+)-discodermolide. Combined with asymmetric catalytic diboration, hydroformylation, and borylative aldehyde–diene coupling reactions, (+)-discodermolide could then be prepared from simple hydrocarbon-based building blocks.

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Self-Assembly

Reversible Supramolecular Assembly at Specific DNA Sites: Nickel-Promoted Bivalent DNA Binding with Designed Peptide and Bipyridyl–Bis(benzamidine) Components

Mateo I. Sánchez, Jesús Mosquera, Prof. M. Eugenio Vázquez and Prof. José L. Mascareñas

Reversible Supramolecular Assembly at Specific DNA Sites: Nickel-Promoted Bivalent DNA Binding with Designed Peptide and Bipyridyl–Bis(benzamidine) ComponentsNickel(II) salts promote the assembly of a bis(histidine)-modified peptide that is derived from a bZIP transcription factor and a bipyridine-substituted bis(benzamidine) unit at specific DNA sites. This supramolecular system features some key properties of naturally occurring DNA-binding proteins, such as bivalence, selectivity, responsiveness to external agents, and reversibility.

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Polymeric Catalysts

A Polyphenylene Support for Pd Catalysts with Exceptional Catalytic Activity

Dr. Feng Wang, Jerrik Mielby, Dr. Felix Herrmann Richter, Dr. Guanghui Wang, Dr. Gonzalo Prieto, Dr. Takeshi Kasama, Dr. Claudia Weidenthaler, Hans-Josef Bongard, Prof. Dr. Søren Kegnæs, Prof. Dr. Alois Fürstner and Prof. Dr. Ferdi Schüth

A Polyphenylene Support for Pd Catalysts with Exceptional Catalytic ActivitySupport with benefits: A composite catalyst is synthesized by palladium-catalyzed Suzuki coupling which directly results in formation of palladium nanoparticles confined to a porous polyphenylene network. A polyphenylene support serves as an excellent platform for metal-catalyzed reactions, which are typically carried out under homogeneous conditions.

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Photochemistry

Selective Photoelectrochemical Reduction of Aqueous CO2 to CO by Solvated Electrons

Linghong Zhang, Di Zhu, Prof. Gilbert M. Nathanson and Prof. Robert J. Hamers

Selective Photoelectrochemical Reduction of Aqueous CO2 to CO by Solvated ElectronsDiamond in the rough: Illumination of diamond substrates leads to emission of electrons into aqueous media. The solvated electrons are potent reducing agents and induce the direct one-electron reduction of CO2 to CO2.−, which then forms CO. This approach represents a new concept in catalysis by directly releasing electrons into reactant liquids.

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Fluorination

Mild and Versatile Nitrate-Promoted C[BOND]H Bond Fluorination

Dr. Shao-Jie Lou, Prof. Dan-Qian Xu and Prof. Zhen-Yuan Xu

Mild and Versatile Nitrate-Promoted C<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />H Bond FluorinationNitrate makes it possible: A novel and facile method for C[BOND]H bond fluorination entails remarkably mild reaction conditions (close to room temperature in most cases). Both aromatic and olefinic C(sp2)[BOND]H bonds were selectively fluorinated in the presence of a catalytic amount of inexpensive and nontoxic nitrate as the promoter.

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Water Structuring

Charge Asymmetry at Aqueous Hydrophobic Interfaces and Hydration Shells

Dr. Rüdiger Scheu, Blake M. Rankin, Yixing Chen, Dr. Kailash C. Jena, Prof. Dr. Dor Ben-Amotz and Prof. Dr. Sylvie Roke

Charge Asymmetry at Aqueous Hydrophobic Interfaces and Hydration ShellsGuilty as charged: Water is often modeled as a dielectric continuum, but the molecular structure of water is asymmetric. Two ions that have a virtually identical size, shape, and structure, but an opposite charge sign have been investigated to see whether charge makes a fundamental difference to water structuring. The spectroscopic data for the hydration and interface structures are found to be remarkably different for opposite charges.

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Organo Cascade Reactions

Asymmetric Synthesis of Highly Substituted β-Lactones through Oxidative Carbene Catalysis with LiCl as Cooperative Lewis Acid

Srikrishna Bera, Dr. Ramesh C. Samanta, Dr. Constantin G. Daniliuc and Prof. Dr. Armido Studer

Asymmetric Synthesis of Highly Substituted β-Lactones through Oxidative Carbene Catalysis with LiCl as Cooperative Lewis AcidHighly substituted β-lactones are generated by NHC catalysis of enals with β-diketones, β-ketoesters, and malonates bearing a β-oxyalkyl substituent at the α-position. LiCl acts as cooperative Lewis acid. The organocascade comprises two C[BOND]C bond formations and one C[BOND]O bond formation. Up to four contiguous stereogenic centers including two fully substituted stereocenters are formed with high diastereo- and enantioselectivity.

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Chemical Linguistics

Organic Chemistry as a Language and the Implications of Chemical Linguistics for Structural and Retrosynthetic Analyses

Dr. Andrea Cadeddu, Elizabeth K. Wylie, Prof. Dr. Janusz Jurczak, Matthew Wampler-Doty and Prof. Dr. Bartosz A. Grzybowski

Organic Chemistry as a Language and the Implications of Chemical Linguistics for Structural and Retrosynthetic AnalysesChemistry is a language: Formal analysis confirms Lehn’s analogy between chemistry and a natural language. English language patterns and the structural motifs of organic molecules follow the same statistics. The methods of computational linguistics can thus be applied to organic molecules to identify characteristic, information-rich patterns defining symmetry/repeat sub-units and bonds amenable to retrosynthetic disconnections.

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Energetic Materials

Chlorine-Free Pyrotechnics: Copper(I) Iodide as a “Green” Blue-Light Emitter

Prof. Dr. Thomas M. Klapötke, Dr. Magdalena Rusan and Dr. Jesse J. Sabatini

Chlorine-Free Pyrotechnics: Copper(I) Iodide as a “Green” Blue-Light EmitterOut of the blue: A suitable blue-light-emitting pyrotechnic with low sensitivities to various ignition stimuli has been developed without the need to employ chlorine-containing materials. With copper(I) iodide proven as a suitable blue-light emitter in pyrotechnics, the risk of generating highly carcinogenic polychlorinated aromatic compounds during the combustion process is eliminated.

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Doped Ceria

Defect Chemistry of Singly and Doubly Doped Ceria: Correlation between Ion Transport and Energetics

Dr. Salih Buyukkilic, Prof. Sangtae Kim and Prof. Alexandra Navrotsky

Defect Chemistry of Singly and Doubly Doped Ceria: Correlation between Ion Transport and EnergeticsA unique correlation: The correlation between the energetics and the ionic conductivity, σi, of ceria that was singly or doubly doped with neodymia and samaria has now also been confirmed for high temperatures. The maximum formation enthalpy of the oxide solid solution, ΔHf,ox, coincides with the maximum σi at/near dopant fractions of 0.10, 0.15, and 0.20 in Ce1−xNdxO2−0.5x, Ce1−xSmxO2−0.5x, and Ce1−xSm0.5xNd0.5xO2−0.5x, respectively.

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Macroscopic Objects

Cooperative, Reversible Self-Assembly of Covalently Pre-Linked Proteins into Giant Fibrous Structures

Saadyah Averick, Orsolya Karácsony, Jacob Mohin, Dr. Xin Yong, Nicholas M. Moellers, Bradley F. Woodman, Prof. Weipu Zhu, Prof. Ryan A. Mehl, Prof. Anna C. Balazs, Prof. Tomasz Kowalewski and Prof. Krzysztof Matyjaszewski

Cooperative, Reversible Self-Assembly of Covalently Pre-Linked Proteins into Giant Fibrous StructuresProtein oligomers, prepared from diazido GFP (green fluorescent protein) and dialkyne PEO (poly(ethylene oxide)), self-assemble into micrometer scale objects. The dynamics of protein assembly were elucidated and the driving force for fiber formation is the discrete interactions of hydrophobic residues on GFP.

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Anticancer Agents

Analysis of Diazofluorene DNA Binding and Damaging Activity: DNA Cleavage by a Synthetic Monomeric Diazofluorene

Dr. Christina M. Woo, Dr. Nihar Ranjan, Dr. Dev P. Arya and Dr. Seth B. Herzon

Analysis of Diazofluorene DNA Binding and Damaging Activity: DNA Cleavage by a Synthetic Monomeric DiazofluoreneA potent cleaving agent: Diazofluorene-containing natural products are potent cytotoxic agents that damage DNA. The factors governing DNA binding and cleavage by synthetic and natural diazofluorenes are elucidated, and it is shown that the simple monomeric diazofluorene 1 cleaves DNA in tissue culture, suggesting its application in translational development.

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Protein–Protein Interactions

The Structure of a Transient Complex of a Nonribosomal Peptide Synthetase and a Cytochrome P450 Monooxygenase

Kristina Haslinger, Dr. Clara Brieke, Dr. Stefanie Uhlmann, Lina Sieverling, Prof. Dr. Roderich D. Süssmuth and Dr. Max J. Cryle

The Structure of a Transient Complex of a Nonribosomal Peptide Synthetase and a Cytochrome P450 MonooxygenaseCaught in the act: The structural characterization of a transient complex between the carrier protein (CP) domain of a nonribosomal peptide synthetase (NRPS) and a Cytochrome P450 oxidase was made possible through the use of covalent inhibitor-type compounds. The structure reveals a novel binding site on the CP for such tailoring enzymes and suggests that the selectivity involves manipulation of the CP tertiary structure.

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Molecular Automata

Visual Displays that Directly Interface and Provide Read-Outs of Molecular States via Molecular Graphics Processing Units

Julia E. Poje, Tamara Kastratovic, Andrew R. Macdonald, Ana C. Guillermo, Steven E. Troetti, Dr. Omar J. Jabado, M. Leigh Fanning, Prof. Darko Stefanovic and Dr. Joanne Macdonald

Visual Displays that Directly Interface and Provide Read-Outs of Molecular States via Molecular Graphics Processing UnitsMolecular computing: Graphics processing units made from molecular circuits can monitor nucleic acids and output alphanumerical read-outs via a fluorescent display. A molecular 7-segment display, a molecular calculator able to add and multiply small numbers, and a molecular automaton able to diagnose viral nucleic acid sequences are reported. These units provide insight for the construction of autonomous biosensing devices and computing platforms devoid of electronics.

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DNA-Encoded Library

Selection of DNA-Encoded Small Molecule Libraries Against Unmodified and Non-Immobilized Protein Targets

Peng Zhao, Zitian Chen, Yizhou Li, Dawei Sun, Yuan Gao, Prof. Yanyi Huang and Prof. Xiaoyu Li

Selection of DNA-Encoded Small Molecule Libraries Against Unmodified and Non-Immobilized Protein TargetsThe requirement for modified and immobilized targets remains a significant disadvantage in the selection of DNA-encoded libraries against biological targets. By using a terminal protection strategy and ligand-induced target photo-crosslinking, iterated selections of DNA-encoded libraries can be realized with unmodified and non-immobilized target proteins.

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Crystallization

“CLASSIC NMR”: An In-Situ NMR Strategy for Mapping the Time-Evolution of Crystallization Processes by Combined Liquid-State and Solid-State Measurements

Dr. Colan E. Hughes, P. Andrew Williams and Prof. Kenneth D. M. Harris

“CLASSIC NMR”: An In-Situ NMR Strategy for Mapping the Time-Evolution of Crystallization Processes by Combined Liquid-State and Solid-State MeasurementsKilling two birds with one stone: A new in-situ NMR strategy (termed CLASSIC NMR) for mapping the evolution of crystallization processes is reported, involving simultaneous measurement of both liquid-state and solid-state NMR spectra as a function of time. This combined strategy allows complementary information to be obtained on the evolution of the solid phase during the crystallization process as well as the corresponding changes in the solution phase.

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Self-Healing Materials

Enzymetically Regulating the Self-Healing of Protein Hydrogels with High Healing Efficiency

Dr. Yuzhou Gao, Prof. Quan Luo, Shanpeng Qiao, Liang Wang, Prof. Zeyuan Dong, Jiayun Xu and Prof. Junqiu Liu

Enzymetically Regulating the Self-Healing of Protein Hydrogels with High Healing EfficiencyEnzyme-mediated self-healing of dynamic covalent bond-driven protein hydrogels was realized by the synergy of two enzymes, glucose oxidase (GOX) and catalase (CAT). The dual-enzyme-mediated protein hydrogels exhibit excellent self-healing properties with 100 % recovery. The self-healing process was reversible and effective with an external glucose stimulus at room temperature.

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Organo-Photocatalysis

Light-Driven Organocatalysis Using Inexpensive, Nontoxic Bi2O3 as the Photocatalyst

Dr. Paola Riente, Alba Matas Adams, Dr. Josep Albero, Prof. Emilio Palomares and Prof. Miquel A. Pericàs

Light-Driven Organocatalysis Using Inexpensive, Nontoxic Bi2O3 as the PhotocatalystNow it’s bismuth time! The asymmetric intermolecular α-alkylation of aldehydes with α-bromocarbonyl compounds can be achieved under visible-light irradiation by combining the second-generation MacMillan catalyst and an inexpensive, nontoxic, and commercially available Bi2O3 powder. This reaction also proceeded with high efficiency when the reaction vial was exposed to the morning sunlight in Tarragona, Spain.

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Water Splitting

Plasmon-Assisted Water Splitting Using Two Sides of the Same SrTiO3 Single-Crystal Substrate: Conversion of Visible Light to Chemical Energy

Yuqing Zhong, Prof. Kosei Ueno, Yuko Mori, Dr. Xu Shi, Dr. Tomoya Oshikiri, Prof. Kei Murakoshi, Prof. Haruo Inoue and Prof. Hiroaki Misawa

Plasmon-Assisted Water Splitting Using Two Sides of the Same SrTiO3 Single-Crystal Substrate: Conversion of Visible Light to Chemical EnergyPhotochemistry: A plasmon-induced water splitting system that operates under irradiation by visible light using both sides of the same SrTiO3 substrate is reported (see picture). The hydrogen-evolution action spectrum closely corresponds to the plasmon resonance spectrum, indicating that the plasmon-induced charge separation at the Au/SrTiO3 interface promotes water oxidation and the reduction of protons.

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Dye-labeled Ts1 toxin

Total Chemical Synthesis of Biologically Active Fluorescent Dye-Labeled Ts1 Toxin

Bobo Dang, Dr. Tomoya Kubota, Prof. Dr. Ana M. Correa, Prof. Dr. Francisco Bezanilla and Prof. Dr. Stephen B. H. Kent

Total Chemical Synthesis of Biologically Active Fluorescent Dye-Labeled Ts1 ToxinModern ligation methods were used to establish the total chemical synthesis of the Ts1 protein. By using click chemistry the synthetic Ts1 molecule was site-specifically labeled with fluorescent dyes. Dye-labeled Ts1 protein bound to the voltage-gated sodium channel Nav and modified its voltage dependence.

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Nanomedicine

Development of Multinuclear Polymeric Nanoparticles as Robust Protein Nanocarriers

Dr. Jun Wu, Dr. Nazila Kamly, Dr. Jinjun Shi, Lili Zhao, Dr. Zeyu Xiao, Geoffrey Hollett, Rohit John, Shaunak Ray, Dr. Xiaoyang Xu, Dr. Xueqing Zhang, Prof. Philip W. Kantoff and Prof. Omid C. Farokhzad

Development of Multinuclear Polymeric Nanoparticles as Robust Protein NanocarriersPolymer–polycation nanoparticles have been used as nuclei to readily adsorb large amounts of protein (>20 % of the nanoparticles by weight) to form new hybrid nanospheres with diameters <200 nm in aqueous solutions without organic solvents through electrostatic interactions. This model system was used to demonstrate the relationships between nanosphere size, surface charge, polymer–polycation composition, and protein loading.

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Triazole Synthesis

A Metal-Free Three-Component Reaction for the Regioselective Synthesis of 1,4,5-Trisubstituted 1,2,3-Triazoles

Dr. Joice Thomas, Dr. Jubi John, Nikita Parekh and Prof. Dr. Wim Dehaen

A Metal-Free Three-Component Reaction for the Regioselective Synthesis of 1,4,5-Trisubstituted 1,2,3-TriazolesFully functionalized 1,2,3-triazoles were obtained by a metal-free three-component reaction. Simple and readily available building blocks were employed in this organocatalytic transformation, which gave the desired products in good yield and with high regioselectivity. Most of the synthesized triazoles were previously inaccessible.

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Synthetic Molecular Machines

Motion Capture and Manipulation of a Single Synthetic Molecular Rotor by Optical Microscopy

Dr. Tomohiro Ikeda, Takahiro Tsukahara, Prof. Ryota Iino, Prof. Masayuki Takeuchi and Prof. Hiroyuki Noji

Motion Capture and Manipulation of a Single Synthetic Molecular Rotor by Optical MicroscopySingle-molecule optical microscopy was applied to study the rotation of a double-decker porphyrin. With a magnetic bead as the probe, the rotary diffusion of this synthetic nanorotor with 90° steps was visualized; it is consistent with the four-fold structural symmetry of this molecule.

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Lamellae from Rods

“Raft” Formation by Two-Dimensional Self-Assembly of Block Copolymer Rod Micelles in Aqueous Solution

Dr. Georgios Rizis, Prof. Theo G. M. van de Ven and Prof. Adi Eisenberg

“Raft” Formation by Two-Dimensional Self-Assembly of Block Copolymer Rod Micelles in Aqueous SolutionA novel mechanism of lamella formation is described, which involves the hierarchical self-assembly of poly(ethylene oxide)-block-polycaprolactone micelles in water. Spheres transform first into rods, which then align spontaneously and associate laterally to form extended lamellar sheets. These self-assembled lamellar “rafts” are, thus, quite different from the traditional chain-folded crystalline lamellae.

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Zintl Ions

Bi[BOND]Zn Bond Formation in Liquid Ammonia Solution: [Bi[BOND]Zn[BOND]Bi]4−, a Linear Polyanion that is Iso(valence)-electronic to CO2

Christian B. Benda, Tobias Köchner, Raphaela Schäper, Prof. Dr. Stephan Schulz and Prof. Dr. Thomas F. Fässler

Bi<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />Zn Bond Formation in Liquid Ammonia Solution: [Bi<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />Zn<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />Bi]4−, a Linear Polyanion that is Iso(valence)-electronic to CO2Metallic carbon dioxide: The metal atoms Bi and Zn form two isomers, molecular [Bi[BOND]Zn[BOND]Bi]4− and polymeric equation image{[ZnBi2]4−}, whereas iso(valence)-electronic CO2 and SiS2 adopt only one form under standard conditions. The linear anion [Bi[BOND]Zn[BOND]Bi]4− found in the compound K4[ZnBi2](NH3)12 is formed in the reaction of a low-valent ZnI compound with a solution of the neat solid K3Bi2 in liquid ammonia under mild reaction conditions.

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Protein Structures

Collisional and Coulombic Unfolding of Gas-Phase Proteins: High Correlation to Their Domain Structures in Solution

Yueyang Zhong, Linjie Han and Brandon T. Ruotolo

Collisional and Coulombic Unfolding of Gas-Phase Proteins: High Correlation to Their Domain Structures in SolutionGas-phase unfolding is used as a means to determine the number of autonomously folded domains within monomeric proteins. Ion-mobility mass spectrometry data show a strong, positive correlation between the number of protein unfolding transitions observed in the gas phase and the number of known domains within a group of sixteen proteins ranging from 8–78 kDa. CCS=collision cross-section.

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Heterogeneous Catalysis

Trinuclear Gold Clusters Supported by Cyclic (alkyl)(amino)carbene Ligands: Mimics for Gold Heterogeneous Catalysts

Dr. Liqun Jin, David S. Weinberger, Dr. Mohand Melaimi, Dr. Curtis E. Moore, Prof. Arnold L. Rheingold and Prof. Guy Bertrand

Trinuclear Gold Clusters Supported by Cyclic (alkyl)(amino)carbene Ligands: Mimics for Gold Heterogeneous CatalystsWell-defined clusters supported by three cyclic (alkyl)(amino)carbenes (CAACs), or two CAACs and a phosphine, can be prepared by ligand exchange. These mixed-valence gold(I)/gold(0) clusters promote the catalytic carbonylation of amines by the formation of di- or trinuclear gold(I) complexes, which can be isolated.

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Energetic Materials

Potassium 1,1′-Dinitramino-5,5′-bistetrazolate: A Primary Explosive with Fast Detonation and High Initiation Power

Dennis Fischer, Prof. Dr. Thomas M. Klapötke and Dr. Jörg Stierstorfer

Potassium 1,1′-Dinitramino-5,5′-bistetrazolate: A Primary Explosive with Fast Detonation and High Initiation PowerFast and furious: The picture shows the moment of detonation of the new primary explosive potassium 1,1′-dinitramino-5,5′-bistetrazolate, which can be synthesized by a safe and sustainable procedure. It shows faster detonation with greater initiation power than lead azide while simultaneously being environmentally compatible.

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Access to β-Lactams by Enantioselective Palladium(0)-Catalyzed C(sp3)[BOND]H Alkylation

Julia Pedroni, Michele Boghi, Dr. Tanguy Saget and Prof. Dr. Nicolai Cramer

Access to β-Lactams by Enantioselective Palladium(0)-Catalyzed C(sp3)<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" />H AlkylationStrain away: Chiral β-lactams are obtained from readily accessible chloroacetamides by an asymmetric palladium(II)-catalyzed C[BOND]H functionalization in high yields and excellent enantioselectivities. Important aspects of this transformation are the challenging strain-building C(sp3)[BOND]C(sp3) reductive elimination to form the four-membered ring. Ad=adamanyl.

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Photochemistry

[2+2] Cycloaddition of 1,3-Dienes by Visible Light Photocatalysis

Anna E. Hurtley, Dr. Zhan Lu and Prof. Tehshik P. Yoon

[2+2] Cycloaddition of 1,3-Dienes by Visible Light PhotocatalysisSquare dance: A convenient and highly functional-group-tolerant [2+2] cycloaddition of 1,3-dienes that operates under visible light irradiation is reported. The vinylcyclobutane products serve as versatile synthetic intermediates in a range of further transformations as illustrated by a concise synthesis of the marine natural product (±)-epiraikovenal. bpy=bipyridyl, ppy=phenylpyridyl.

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Protein–Protein Interactions

An Unusual Protein–Protein Interaction through Coupled Unfolding and Binding

Tae-Kyung Yu, Seung-A Shin, Eun-Hee Kim, Dr. Sunghyun Kim, Dr. Kyung-Seok Ryu, Dr. Haekap Cheong, Prof. Dr. Hee-Chul Ahn, Prof. Dr. Sangyong Jon and Prof. Dr. Jeong-Yong Suh

An Unusual Protein–Protein Interaction through Coupled Unfolding and BindingUnfold and hold: It is known that protein–protein interactions can involve coupled folding and binding, but coupled unfolding and binding is not well characterized. An unusual protein–protein interaction is described in which the binding of an aptide (APT) to fibronectin extradomain B (EDB) involves partial unfolding to expose the binding surface. The structural and energetic details were determined by NMR spectroscopy and thermodynamic analysis.

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Nucleophilic Boron

Isolation of a Bis(oxazol-2-ylidene)–Phenylborylene Adduct and its Reactivity as a Boron-Centered Nucleophile

Dr. Lingbing Kong, Dr. Yongxin Li, Dr. Rakesh Ganguly, Prof. Dr. Dragoslav Vidovic and Prof. Dr. Rei Kinjo

Isolation of a Bis(oxazol-2-ylidene)–Phenylborylene Adduct and its Reactivity as a Boron-Centered NucleophileTwo oxazol-2-ylidene ligands effectively stabilize a phenylborylene fragment that features a lone pair of electrons on the boron atom. There are eight electrons around the tricoordinate boron center (8-B-3), and the nucleophilic boron center readily reacts with an electrophile, such as a proton or a transition-metal species, to form a boronium species and a metal–borylene complex, respectively.

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Ketenes

The Ketene-Surrogate Coupling: Catalytic Conversion of Aryl Iodides into Aryl Ketenes through Ynol Ethers

Wenhan Zhang and Dr. Joseph M. Ready

The Ketene-Surrogate Coupling: Catalytic Conversion of Aryl Iodides into Aryl Ketenes through Ynol EthersSetting a trap: Coupling of a terminal ynol ether with aryl iodides enables a catalytic synthesis of aryl ketenes. In situ trapping with nucleophiles provides a wide array of aryl acetic acids and benzyl ketones with only HI and isobutylene as chemical waste. The aryl ketenes additionally participate in electrocyclic ring closure to yield naphthols and quinolines.

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Pyrrole Synthesis

Catalyst-Dependent Divergent Synthesis of Pyrroles from 3-Alkynyl Imine Derivatives: A Noncarbonylative and Carbonylative Approach

Gen-Qiang Chen, Xiao-Nan Zhang, Yin Wei, Dr. Xiang-Ying Tang and Dr. Min Shi

Catalyst-Dependent Divergent Synthesis of Pyrroles from 3-Alkynyl Imine Derivatives: A Noncarbonylative and Carbonylative ApproachCarbonylation or not: A novel Ru0- and RhI-catalyzed noncarbonylative and carbonylative synthesis of multisubstituted pyrroles from readily available 3-alkynyl imine derivatives has been developed. The key steps involve an oxidative addition and a 1,2-alkyl shift, respectively.

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Homogeneous Catalysis

Broad-Spectrum Catalysts for the Ambient Temperature Anti-Markovnikov Hydration of Alkynes

Dr. Le Li, Mingshuo Zeng and Dr. Seth B. Herzon

Broad-Spectrum Catalysts for the Ambient Temperature Anti-Markovnikov Hydration of AlkynesAlkyne hydration: Half-sandwich ruthenium complexes derived from 5,5′-bis(trifluoromethyl)-2,2′-bipyridine show a high activity for the anti-Markovnikov hydration of terminal alkynes (see picture). A wide array of alkynes are efficiently hydrated to aldehydes using 2 mol % metal loadings at 25 °C within 8–24 h.

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Prebiotic Chemistry

A Plausible Simultaneous Synthesis of Amino Acids and Simple Peptides on the Primordial Earth

Eric T. Parker, Dr. Manshui Zhou, Dr. Aaron S. Burton, Dr. Daniel P. Glavin, Dr. Jason P. Dworkin, Prof. Dr. Ramanarayanan Krishnamurthy, Prof. Dr. Facundo M. Fernández and Prof. Dr. Jeffrey L. Bada

A Plausible Simultaneous Synthesis of Amino Acids and Simple Peptides on the Primordial EarthPrebiotic polymerization: Archived samples from Stanley Miller’s previously unreported 1958 cyanamide experiment were investigated to evaluate cyanamide-mediated amino acid polymerization under prebiotic conditions. Aqueous heating experiments indicate that in the presence of an amino acid amide, the dimerization of cyanamide under the mildly basic conditions of the spark-discharge experiment significantly enhances polymerization reactions.

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Structurally Uniform Nanosheets

Structurally Homogeneous Nanosheets from Self-Assembly of a Collagen-Mimetic Peptide

Tao Jiang, Dr. Chunfu Xu, Dr. Xiaobing Zuo and Prof. Vincent P. Conticello

Structurally Homogeneous Nanosheets from Self-Assembly of a Collagen-Mimetic PeptideAmp-ed up self-assembly: A triblock collagen-mimetic peptide, NSIII, self-assembles into a monodisperse population of nanosheets of defined size and shape. The experimental evidence suggests that the presence of 4S-aminoproline (amp) in the peptide sequence imposes stereoelectronic constraints on the conformation of the triple helix that restricts the size distribution of the resultant nanosheets.

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Zeolite Synthesis

Synthesis of a Specified, Silica Molecular Sieve by Using Computationally Predicted Organic Structure-Directing Agents

Joel E. Schmidt, Dr. Michael W. Deem and Dr. Mark E. Davis

Synthesis of a Specified, Silica Molecular Sieve by Using Computationally Predicted Organic Structure-Directing AgentsExperimental validation has been realized of a computational method that is able to screen a large number of organic structure-directing agents (OSDAs). The study shows that the method is able to successfully predict OSDAs for a specified framework by using known chemical reactions, and yield predicted occupancies that are measured in the products (see the calculated structure of STW with occluded pentamethylimidazolium).

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Synthetic Methods

Synthesis of (Carbo)nucleoside Analogues by [3+2] Annulation of Aminocyclopropanes

Sophie Racine, Florian de Nanteuil, Eloisa Serrano and Prof. Dr. Jérôme Waser

Synthesis of (Carbo)nucleoside Analogues by [3+2] Annulation of Aminocyclopropanes(Carbo)nucleoside derivatives constitute an important class of pharmaceuticals. The first synthesis of thymine-, uracil-, and 5-fluorouracil-substituted diester donor–acceptor cyclopropanes and their use in indium- and tin-catalyzed [3+2] annulations with aldehydes, ketones, and enol ethers is described. The method gave access to (carbo)nucleoside analogues in only few steps and will be highly useful for the synthesis of libraries of bioactive compounds.

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Sodium-Ion Batteries

An Ultrastable Anode for Long-Life Room-Temperature Sodium-Ion Batteries

Dr. Haijun Yu, Dr. Yang Ren, Dongdong Xiao, Shaohua Guo, Dr. Yanbei Zhu, Dr. Yumin Qian, Prof. Lin Gu and Prof. Haoshen Zhou

An Ultrastable Anode for Long-Life Room-Temperature Sodium-Ion BatteriesCycle stability: When a novel and ultrastable P2-type titanium-based material was used as the anode, a sodium-ion battery with a long cycle life was obtained. A capacity retention of 84.84 % after 3000 cycles and a small volume contraction of only 0.046 % after 500 cycles lead to the outstanding cycle stability.

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Bioanalysis

A Supercharged Fluorescent Protein as a Versatile Probe for Homogenous DNA Detection and Methylation Analysis

Chunyang Lei, Dr. Yan Huang, Prof. Dr. Zhou Nie, Jun Hu, Lijun Li, Guoyan Lu, Yitao Han and Prof. Dr. Shouzhuo Yao

A Supercharged Fluorescent Protein as a Versatile Probe for Homogenous DNA Detection and Methylation AnalysisSupercharged protein sensor: Taking supercharged green fluorescent protein (ScGFP) as the signal reporter, a simple turn-on homogenous method for DNA detection and methylation analysis of cancer tissue samples has been developed based on the polyionic nanoscale complex of ScGFP/DNA and toehold-mediated strand displacement.

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Bio-reduction

Bio-reduction of Redox-Sensitive Albumin Conjugates in FcRn-Expressing Cells

Lorine Brülisauer, Gina Valentino, Sakura Morinaga, Kübra Cam, Dr. Jens Thostrup Bukrinski, Prof. Dr. Marc A. Gauthier and Prof. Dr. Jean-Christophe Leroux

Bio-reduction of Redox-Sensitive Albumin Conjugates in FcRn-Expressing CellsDisulfide-containing IgG-, Fc-, or albumin-based prodrugs that rely on FcRn-trafficking by endothelial cells for prolonged circulation in the body might be hampered by premature bio-reduction processes during FcRn-recycling events. A detailed bio-reduction analysis of redox-sensitive albumin conjugates in two FcRn-expressing cell lines has been performed. New insights are provided to improve the performance of these classes of therapeutics.

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Stable Gold Carbene

Isolation of a Non-Heteroatom-Stabilized Gold–Carbene Complex

M. Sc. Matthias W. Hussong, Dr. Frank Rominger, Petra Krämer and Prof. Dr. Bernd F. Straub

Isolation of a Non-Heteroatom-Stabilized Gold–Carbene ComplexGold: more than just a “soft proton”: The preparation of the gold complex [IPr**Au[DOUBLE BOND]CMes2]NTf2 was made possible by the extreme steric shielding of the IPr** ancillary ligand (Ar=para-C6H4tBu) and the dimesitylcarbene. The strong bathochromic shift from the red-purple carbenium ion [Mes2CH]+ to the emerald-green gold–carbene cation literally shows that the carbene interaction with gold is more complex than its bonding to a proton.

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Metal–Organic Frameworks

Hydrogen Storage in a Potassium-Ion-Bound Metal–Organic Framework Incorporating Crown Ether Struts as Specific Cation Binding Sites

Dr. Dae-Woon Lim, Seung An Chyun and Prof. Myunghyun Paik Suh

Hydrogen Storage in a Potassium-Ion-Bound Metal–Organic Framework Incorporating Crown Ether Struts as Specific Cation Binding SitesCrown ethers strut their stuff: The metal–organic framework SNU-200 incorporates 18-crown-6 moieties as a cation binding site. SNU-200 binds K+, NH4+, and methyl viologen2+ (MV2+) and their counteranions. Its gas sorption properties depend on the bound cation. The K+/SCN bound SNU-200 shows the highest isosteric heat (9.92 kJ mol−1) of H2 adsorption, a result of the open metal sites on the K+ ions.

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Nanoparticles

Evidence of a Kinetic Isotope Effect in Nanoaluminum and Water Combustion

Dr. Bryce C. Tappan, Dr. Matthew R. Dirmyer and Dr. Grant A. Risha

Evidence of a Kinetic Isotope Effect in Nanoaluminum and Water CombustionBurning insights: Kinetic limitation of nanoparticulate aluminum (nAl) combustion has never been observed and therefore is often described as solely diffusion controlled. The combustion analysis of nAl with H2O or D2O is presented and a distinct kinetic isotope effect measured. This first-ever observed kinetic isotope effect in metal combustion verifies that reaction kinetics play a major role in determining the global burning rate as particle sizes reach the nanoscale.

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Metalloenzyme Design

A De Novo Designed Metalloenzyme for the Hydration of CO2

Dr. Virginia M. Cangelosi, Dr. Aniruddha Deb, Prof. James E. Penner-Hahn and Prof. Vincent L. Pecoraro

A De Novo Designed Metalloenzyme for the Hydration of CO2Chasing down the cheetah: A synthetic metalloenzyme was created that is capable of catalyzing the hydration of carbon dioxide with an efficiency within 1400-fold of carbonic anhydrase II, one of the most efficient enzymes known. This designed zinc enzyme performs better than small-molecule models of carbonic anhydrase. Picture: Zn purple, N dark blue, O red, C cyan.

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Photodegradable Hydrogels

Photodegradable Hydrogels for Capture, Detection, and Release of Live Cells

Dr. Dong-Sik Shin, Dr. Jungmok You, Ali Rahimian, Tam Vu, Christian Siltanen, Arshia Ehsanipour, Dr. Gulnaz Stybayeva, Prof. Julie Sutcliffe and Prof. Alexander Revzin

Photodegradable Hydrogels for Capture, Detection, and Release of Live CellsFunction-based cell retrieval: The function-based sorting of live cells is enabled by a photodegradable poly(ethylene glycol) hydrogel. Hydrogel-coated substrates were used to isolate T-cells from a heterogeneous mixture of immune cells, to analyze cytokine secretion on a cell-by-cell basis, and then to release cells that are actively producing cytokines. TNF=tumor necrosis factor.

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Amyloid Inhibitors

Rational Design and Identification of a Non-Peptidic Aggregation Inhibitor of Amyloid-β Based on a Pharmacophore Motif Obtained from cyclo[-Lys-Leu-Val-Phe-Phe-]

Tadamasa Arai, Takushi Araya, Dr. Daisuke Sasaki, Dr. Atsuhiko Taniguchi, Dr. Takeshi Sato, Dr. Youhei Sohma and Prof. Motomu Kanai

Rational Design and Identification of a Non-Peptidic Aggregation Inhibitor of Amyloid-β Based on a Pharmacophore Motif Obtained from cyclo[-Lys-Leu-Val-Phe-Phe-]A unique pharmacophore motif for aggregation inhibitors of Alzheimer’s amyloid β (Aβ), without the involvement of backbone amide moieties (see picture; right), was identified based on structure–activity relationship studies using cyclo-[KLVFF] (left). This allowed non-peptidic, small-molecule aggregation inhibitors to be designed that possess significant activity that is comparable to the parent cyclic peptides.

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Radiochemistry

A General Copper-Mediated Nucleophilic 18F Fluorination of Arenes

Dr. Matthew Tredwell, Dr. Sean M. Preshlock, Nicholas J. Taylor, Dr. Stefan Gruber, Dr. Mickael Huiban, Dr. Jan Passchier, Dr. Joël Mercier, Dr. Christophe Génicot and Prof. Véronique Gouverneur

A General Copper-Mediated Nucleophilic 18F Fluorination of Arenes18F-labeling for PET: The nucleophilic 18F fluorination of pinacol-derived aryl boronic esters is achieved with [18F]KF/K222 in the presence of [Cu(OTf)2(py)4] (OTf=trifluoromethanesulfonate, py=pyridine); this unprecedented method can produce a clinical dose of 6-[18F]fluoro-L-DOPA in two steps (fluorination followed by deprotection) from a readily available shelf-stable arylBPin precursor (see scheme).

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