Angewandte Chemie International Edition
Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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.
One-Step Formation of “Chain-Armor”-Stabilized DNA Nanostructures
Valentina Cassinelli, Dr. Birgit Oberleitner, Jessica Sobotta, Philipp Nickels, Guido Grossi, Dr. Susanne Kempter, Dr. Thomas Frischmuth, Prof. Tim Liedl and Dr. Antonio Manetto
Interlocked catenane rings consisting of 24 single-stranded DNA molecules (“chain-armor DNA”) were built from six helix tubes containing 3′-alkyne- and 5′-azide-modified single-stranded tiles (SST) that were covalently closed by click chemistry. Intramolecular cyclization stabilized these DNA nanotubes efficiently against enzymatic and thermal degradation.
Rhodium(I)-Catalyzed Sequential C(sp)C(sp3) and C(sp3)C(sp3) Bond Formation through Migratory Carbene Insertion
Ying Xia, Sheng Feng, Zhen Liu, Dr. Yan Zhang and Prof. Dr. Jianbo Wang
All on C: A sequential RhI-catalyzed alkyl and alkynyl coupling on a carbene successively establishes a C(sp)C(sp3) and then a C(sp3)C(sp3) bond on the original carbenic carbon center. The reaction results in the formation of an all-carbon quaternary center in high efficiency. A rhodium–carbene migratory insertion is proposed as the key step in this transformation.
The Mechanism of Ligand-Induced Activation or Inhibition of μ- and κ-Opioid Receptors
Dr. Shuguang Yuan, Prof. Krzysztof Palczewski, Dr. Qian Peng, Dr. Michal Kolinski, Prof. Horst Vogel and Prof. Slawomir Filipek
One rule to link them all: The same ligand can act as an agonist for the κ-opioid receptor (κOR) and as an antagonist for the μ-opioid receptor (μOR). Long-time-scale MD simulations reveal that antagonist binding diminishes the solvent-accessible surface area (SASA) of the binding pocket, which consequently blocks the entrance of water into the receptor, whereas agonist binding leads to comparatively larger SASA values.
From Chemical Gardens to Fuel Cells: Generation of Electrical Potential and Current Across Self-Assembling Iron Mineral Membranes
Dr. Laura M. Barge, Yeghegis Abedian, Dr. Michael J. Russell, Ivria J. Doloboff, Dr. Julyan H. E. Cartwright, Dr. Richard D. Kidd and Dr. Isik Kanik
Chemical gardens: Self-assembling membranes in iron sulfide and iron hydroxide reaction systems were studied. The electrical potential and current generated by precipitation of the inorganic membranes were measured. The battery-like properties of the chemical gardens were demonstrated by linking multiple experiments in series which produced sufficient electrical power to light an external light-emitting diode.
The First Introduction of Graphene to Rechargeable Li–CO2 Batteries
Zhang Zhang, Qiang Zhang, Yanan Chen, Jie Bao, Xianlong Zhou, Zhaojun Xie, Jinping Wei and Prof. Zhen Zhou
A different cathode: The introduction of graphene as a cathode material to Li–CO2 batteries significantly improves their performance. The resulting batteries feature a superior discharge capacity and enhanced cycle stability. A novel approach for simultaneously capturing CO2 and storing energy has thus been developed.
Dynamic Inclusion Complexes of Metal Nanoparticles Inside Nanocups
Mariana Alarcón-Correa, Dr. Tung-Chun Lee and Prof. Dr. Peer Fischer
Nanocup with nanoparticle: Dynamic 1:1 host–guest inclusion complexes of metal nanoparticles inside oxide nanocups are fabricated by means of a reactive double Janus nanoparticle intermediate in a kinetically controlled process. Release of the nanoparticle guests from the nanocups can be efficiently triggered by an external stimulus.
Inhibition of Ras Signaling by Blocking Ras–Effector Interactions with Cyclic Peptides
Dr. Punit Upadhyaya, Dr. Ziqing Qian, Dr. Nicholas G. Selner, Sarah R. Clippinger, Prof. Dr. Zhengrong Wu, Dr. Roger Briesewitz and Prof. Dr. Dehua Pei
Round, round, get around: Cell-permeable cyclic peptides were developed that act as direct Ras inhibitors by blocking Ras–effector protein interactions. These peptides, named cyclorasins, cause growth inhibition and apoptosis in cancer cells.
Oxygen Evolution Reaction
Ultrathin Spinel-Structured Nanosheets Rich in Oxygen Deficiencies for Enhanced Electrocatalytic Water Oxidation
Jian Bao, Dr. Xiaodong Zhang, Bo Fan, Jiajia Zhang, Dr. Min Zhou, Wenlong Yang, Xin Hu, Hui Wang, Prof. Bicai Pan and Prof. Yi Xie
Beneficial deficiencies: A series of spinel-structured nanosheets with oxygen deficiencies (Ovac) and ultrathin thickness were synthesized for the first time. These features lead to an increase in the number of active sites and in the activity of the catalyst in water oxidation, which was confirmed by experimental and theoretical studies.
Photoelectrocyclization as an Activation Mechanism for Organelle-Specific Live-Cell Imaging Probes
Mai N. Tran and Prof. David M. Chenoweth
A photoactivatable organelle-specific live-cell imaging probe based on a 6π electrocyclization/oxidation mechanism is described. This probe is water-soluble, non-cytotoxic, cell-permeable, and can be used for mitochondrial imaging.
Electrokinetic Size and Mobility Traps for On-site Therapeutic Drug Monitoring
Aliaa I. Shallan, Dr. Rosanne M. Guijt and Prof. Michael C. Breadmore
Trapped: The electrokinetic extraction, concentration, and purification of small molecules from biological samples is possible with size and mobility traps. These traps consist of two nanojunctions, with the extraction junction having a larger pore size than the purification junction. The direct analysis of ampicillin levels in a blood sample was achieved in 5 min using this method.
Single Benzene Green Fluorophore: Solid-State Emissive, Water-Soluble, and Solvent- and pH-Independent Fluorescence with Large Stokes Shifts
Teruo Beppu, Kosuke Tomiguchi, Prof. Dr. Akito Masuhara, Prof. Dr. Yong-Jin Pu and Prof. Dr. Hiroshi Katagiri
Evergreen: An effective push–pull system supported by intramolecular hydrogen bonding between amino and sulfonyl groups generated high fluorescence properties. The achievement of a single benzene core fluorescent system (see picture) allowed steady green fluorescence, independent of the surrounding environment such as solvent polarity and pH, as well as extraordinarily large Stokes shifts of up to 140 nm.
A Crystalline Mesoporous Germanate with 48-Ring Channels for CO2 Separation
Dr. Jie Liang, Dr. Jie Su, Xiaodan Luo, Prof. Yingxia Wang, Dr. Haoquan Zheng, Dr. Hong Chen, Prof. Xiaodong Zou, Prof. Jianhua Lin and Prof. Junliang Sun
Germanate zeolites germinate: A novel mesoporous germanate PKU-17 with 3D 48×16×16-ring channels was designed by introducing two large building units (Ge10 and Ge7 clusters) into the same framework. PKU-17 has the largest pore size among germanates. It is also the first germanate that shows a good selectivity toward CO2 over N2 and CH4.
Heterostructure of Si and CoSe2: A Promising Photocathode Based on a Non-noble Metal Catalyst for Photoelectrochemical Hydrogen Evolution
Dr. Mrinmoyee Basu, Zhi-Wei Zhang, Chih-Jung Chen, Po-Tzu Chen, Kai-Chih Yang, Prof. Chong-Geng Ma, Dr. Chun Che Lin, Prof. Dr. Shu-Fen Hu and Prof. Dr. Ru-Shi Liu
Heterostructures of semi-metallic CoSe2 nanorods and p-Si microwires behave as an efficient photocathode for the solar-driven hydrogen evolution reaction. Photocurrents as high as 9 mA cm−2 have been achieved at 0 V vs. reversible hydrogen electrode. The high photocurrents can be attributed to low charge transfer resistance between the Si and CoSe2 interfaces and between the CoSe2 and electrolyte interfaces.
Epitope Targeting of Tertiary Protein Structure Enables Target-Guided Synthesis of a Potent In-Cell Inhibitor of Botulinum Neurotoxin
Blake Farrow, Michelle Wong, Jacquie Malette, Dr. Bert Lai, Dr. Kaycie M. Deyle, Dr. Samir Das, Dr. Arundhati Nag, Dr. Heather D. Agnew and Prof. James R. Heath
Let the toxins pick their poison: The target-guided synthesis of a divalent peptide ligand that is a potent inhibitor of botulinum neurotoxin both in vitro and in cells was achieved. An active-site-binding substrate mimic was combined with epitope targeting of a nearby site in the folded structure of the toxin to obtain the peripheral binder.
polyMOFs: A Class of Interconvertible Polymer-Metal-Organic-Framework Hybrid Materials
Dr. Zhenjie Zhang, Ha Thi Hoang Nguyen, Prof. Dr. Stephen A. Miller and Prof. Dr. Seth M. Cohen
A bottom-up strategy is used to generate porosity from non-porous, one-dimensional, amorphous polymeric materials by their transformation into crystalline polyMOF materials. These materials harness the advantages of the porosity and crystallinity of MOFs along with certain attributes of the polymers, such as facile film formation and greater chemical stability.
Posttranslational Modifications of Intact Proteins Detected by NMR Spectroscopy: Application to Glycosylation
Dr. Mario Schubert, Dr. Michal J. Walczak, Prof. Dr. Markus Aebi and Prof. Dr. Gerhard Wider
No label required: The characterization of structure and function of posttranslational modifications (PTMs) can be very challenging especially for glycans. A direct and simple NMR spectroscopic method for the characterization PTMs requires no isotope labeling and can be applied to proteins of any size provides information not available by more complicated existing techniques.
Magnetic Assembly and Field-Tuning of Ellipsoidal-Nanoparticle-Based Colloidal Photonic Crystals
Mingsheng Wang, Dr. Le He, Wenjing Xu, Xin Wang and Prof. Yadong Yin
The shape of color to come: Magnetic nanoellipsoidal particles have been assembled into a class of uniquely responsive photonic structures whose photonic properties can be dynamically tuned by controlling the direction of magnetic fields.
Photochemical Synthesis of Ultrafine Cubic Boron Nitride Nanoparticles under Ambient Conditions
Hui Liu, Peng Jin, Yan-Ming Xue, Cunku Dong, Xiang Li, Cheng-Chun Tang and Xi-Wen Du
Small phases: A photochemical method is developed to synthesize unprecedentedly small and monodisperse cubic boron nitride (c-BN NPs) nanoparticles of 3.5 nm. Under ambient conditions nanosecond pulsed laser irradiation decomposes ammonia borane (AB) molecules in dioxane solution to give ultrafine c-BN NPs as well as H2 gas. This approach showed great potential for controllable hydrogen generation.
A Small Molecule Walks Along a Surface Between Porphyrin Fences That Are Assembled In Situ
Dr. Sam Haq, Bareld Wit, Hongqian Sang, Dr. Andrea Floris, Prof. Yu Wang, Prof. Jianbo Wang, Dr. Lluïsa Pérez-García, Prof. Lev Kantorovitch, Prof. David B. Amabilino and Prof. Rasmita Raval
Walk the line: A bis(imidazolyl) compound “walks” along an anisotropic monocrystalline copper surface in one preferred direction with remarkably high selectivity. The motion of the walker can be effectively confined by on-surface synthesis of porphyrin oligomer fences oriented orthogonal to the walking direction, which act as insurmountable barriers.
Self-Assembly of Disorazole C1 through a One-Pot Alkyne Metathesis Homodimerization Strategy
Dr. Kevin J. Ralston, Dr. H. Clinton Ramstadius, Richard C. Brewster, Dr. Helen S. Niblock and Dr. Alison N. Hulme
Heads or tails? The self-assembly of disorazole C1, a cytotoxic bis(lactone) natural product, has been achieved through alkyne cross-metathesis and ring-closing alkyne metathesis. The coupling favored the production of the desired head-to-tail dimer over its head-to-head counterpart with a ratio of 5:1.
Electrostatic Assembly/Disassembly of Nanoscaled Colloidosomes for Light-Triggered Cargo Release
Song Li, Basem A. Moosa, Jonas G. Croissant and Prof. Niveen M. Khashab
Nanocapsules for large cargos: Nanoscaled colloidosomes were designed by electrostatic assembly of organosilica nanoparticles (NPs) with oppositely charged surfaces, arising from different contents of a bridged nitrophenylene-alkoxysilane derivative in the silica. The positive charge was reversed by light irradiation because of the photoreaction of nitrophenylene moieties.
Organic Light-Emitting Diodes Using a Neutral π Radical as Emitter: The Emission from a Doublet
Qiming Peng, Ablikim Obolda, Prof. Dr. Ming Zhang and Prof. Dr. Feng Li
Organic electronics: An organic open-shell molecule (TTM-1Cz) was used as an emitter in organic light-emitting diodes (OLEDs). There is only one electron at the highest occupied molecular orbital (see picture), leading to the excited state of TTM-1Cz to be a doublet. The key issue of how to harvest the triplet energy in an OLED is thus circumvented, because the radiative decay of the doublet is totally spin-allowed.
Potential-Dependent Adlayer Structure and Dynamics at the Ionic Liquid/Au(111) Interface: A Molecular-Scale In Situ Video-STM Study
Dr. Rui Wen, Björn Rahn and Prof. Dr. Olaf M. Magnussen
Potentially structured: Au (111) electrodes were studied in the room-temperature ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide by high-speed scanning tunneling microscopy. Two distinct transitions in the molecular arrangement of cations at the interface and their sub-second dynamic behavior are observed with decreasing potential.
Cobalt-Catalyzed Hydrogenation of Esters to Alcohols: Unexpected Reactivity Trend Indicates Ester Enolate Intermediacy
Dr. Dipankar Srimani, Dr. Arup Mukherjee, Dr. Alexander F. G. Goldberg, Dr. Gregory Leitus, Dr. Yael Diskin-Posner, Dr. Linda J. W. Shimon, Yehoshoa Ben David and Prof. Dr. David Milstein
Getting involved: The atom-efficient and environmentally benign catalytic hydrogenation of carboxylic acid esters to alcohols has been accomplished in recent years mainly with precious-metal-based catalysts. Presented here is the first cobalt-catalyzed hydrogenation of esters to alcohols. Unexpectedly, the evidence indicates the unprecedented involvement of ester enolate intermediates.
Micromotor-Based Energy Generation
Dr. Virendra V. Singh, Fernando Soto, Kevin Kaufmann and Prof. Joseph Wang
Fuel metal jacket: Micromotors give enhanced energy generation by the movement of Pt-black/Ti Janus microparticles in liquid-phase chemical fuel. The autonomous motion of these micromotors leads to enhanced mixing and transport of NaBH4 fuel compared to static microparticles or films, and hence to a substantially faster hydrogen-generation rate. The practical utility is illustrated by powering a hydrogen–oxygen fuel cell car.
Targeted Detection of G-Quadruplexes in Cellular RNAs
Dr. Chun Kit Kwok and Prof. Shankar Balasubramanian
Hunting G4s: This study describes a new approach for detecting and mapping RNA G-quadruplexes (G4) in low-abundance cellular transcripts by coupling reverse transcriptase stalling (RTS) and an amplification strategy (HBLMPCR). Rational control of RNA G4-mediated RTS can be achieved by exploiting RNA G4–cation and RNA G4–ligand interactions, as well as use a selective reverse transcriptase for monitoring purposes.
Polyoxometalate Complexes of Anatase-Titanium Dioxide Cores in Water
Dr. Manoj Raula, Gal Gan Or, Marina Saganovich, Dr. Offer Zeiri, Prof. Yifeng Wang, Dr. Michele R. Chierotti, Prof. Roberto Gobetto and Prof. Ira A. Weinstock
Redox-active ligands for TiO2: Polyoxometalate (POM) electron acceptors serve as covalently coordinated inorganic ligands for anatase-TiO2 nanocrystals, giving assemblies positioned between molecular macroanions and traditional colloidal nanoparticles. The POM ligands have tunable redox potentials, providing options for controlling reactions of soluble metal oxide semiconductor nanocrystals.
Controllable Scission and Seamless Stitching of Metal–Organic Clusters by STM Manipulation
Huihui Kong, Likun Wang, Qiang Sun, Chi Zhang, Dr. Qinggang Tan and Prof. Dr. Wei Xu
Lateral STM manipulations enable the controllable scission of a complicated metal–organic cluster consisting of nickel atoms and uracil molecules (see Scheme, left) into its elementary structural motifs (right). Furthermore, the elementary units can be seamlessly stitched back together into the original cluster. STM=scanning tunneling microscopy.
CH Alkenylations with Alkenyl Acetates, Phosphates, Carbonates, and Carbamates by Cobalt Catalysis at 23 °C
M. Sc. Marc Moselage, M. Sc. Nicolas Sauermann, B. Sc. Sven C. Richter and Prof. Dr. Lutz Ackermann
Inexpensive cobalt catalysis enabled the CH alkenylation of unactivated (hetero)arenes with enol derivatives at ambient temperature. The versatile cobalt catalyst was employed for challenging CH/CO cleavage reactions with alkenyl acetates, carbamates, carbonates, and phosphates in a stereoconvergent fashion.
LP99: Discovery and Synthesis of the First Selective BRD7/9 Bromodomain Inhibitor
Peter G. K. Clark, Dr. Lucas C. C. Vieira, Dr. Cynthia Tallant, Dr. Oleg Fedorov, Dr. Dean C. Singleton, Dr. Catherine M. Rogers, Octovia P. Monteiro, James M. Bennett, Dr. Roberta Baronio, Dr. Susanne Müller, Dr. Danette L. Daniels, Jacqui Méndez, Prof. Dr. Stefan Knapp, Dr. Paul E. Brennan and Prof. Dr. Darren J. Dixon
BRD7 and BRD9 are bromodomain proteins and part of some chromatin-remodeling complexes. A fragment lead was rapidly optimized through structure-based design and exploitation of a stereoselective nitro-Mannich/lactamization cascade process to give the first potent and selective BRD7/9 inhibitor, LP99. Treatment with LP99 led to displacement of BRD7 and BRD9 from chromatin and down-regulation of the pro-inflammatory cytokine IL-6.
2D Zeolite Coatings: Langmuir–Schaefer Deposition of 3 nm Thick MFI Zeolite Nanosheets
Neel Rangnekar, Meera Shete, Dr. Kumar Varoon Agrawal, Dr. Berna Topuz, Prashant Kumar, Dr. Qiang Guo, Issam Ismail, Prof. Abdulrahman Alyoubi, Prof. Sulaiman Basahel, Dr. Katabathini Narasimharao, Prof. Christopher W. Macosko, Prof. K. Andre Mkhoyan, Prof. Shaeel Al-Thabaiti, Prof. Benjamin Stottrup and Prof. Michael Tsapatsis
Zeolite films: Acid treatment was used to prepare stable suspensions of MFI zeolite nanosheets in ethanol. Nanosheets from these suspensions showed high surface activity and could be transferred using the Langmuir–Schaefer technique to obtain monolayer coatings (3 nm thick). Secondary growth of the monolayer coatings resulted in sub-12 nm intergrown zeolite thin films.