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.
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.
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.
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.
The Ruthenostannylene Complex [Cp*(IXy)H2Ru-Sn-Trip]: Providing Access to Unusual Ru-Sn Bonded Stanna-imine, Stannene, and Ketenylstannyl Complexes
Hsueh-Ju Liu, Micah S. Ziegler and Prof. Dr. T. Don Tilley
Reactivity studies of the thermally stable ruthenostannylene complex [Cp*(IXy)(H)2RuSnTrip] (1) towards a variety of organic substrates are described. This complex is used for the construction of new metal–tin complexes featuring low-valent or unsaturated tin centers. IXy=1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene; Cp*=η5-C5Me5; Trip=2,4,6-iPr3C6H2.
Reconstitution of Biosynthetic Machinery for the Synthesis of the Highly Elaborated Indole Diterpene Penitrem
Dr. Chengwei Liu, Koichi Tagami, Dr. Atsushi Minami, Tomoyuki Matsumoto, Jens Christian Frisvad, Hideyuki Suzuki, Jun Ishikawa, Katsuya Gomi and Prof. Dr. Hideaki Oikawa
The gene cluster that is responsible for the biosynthesis of the indole diterpene penitrem A has been identified. Thirteen out of the seventeen involved transformations were elucidated by heterologous reconstitution of the relevant genes and found to feature a prenylation-initiated cationic cyclization (PtmE) and two successive P450-catalyzed oxidative reactions to install the bicyclo[4.2.0]heptane skeleton.
Next-Generation Sequencing as Input for Chemometrics in Differential Sensing Routines
Sara Goodwin, Alexandra M. Gade, Michelle Byrom, Baine Herrera, Camille Spears, Dr. Eric V. Anslyn and Dr. Andrew D. Ellington
Keeping score: Nucleic acid sequences and sequence counts were used as multivariate data without the necessity of a spatial array. Aptamers were used as semi-specific receptors for cell line differentiation, and cross-reactivity between the aptamers was observed. The principal component analysis (PCA) generates high-dimensionality score plots, thus differentiating a mixture of complex and subtly different analytes.
Red, Green, and Blue Luminescence by Carbon Dots: Full-Color Emission Tuning and Multicolor Cellular Imaging
Kai Jiang, Shan Sun, Dr. Ling Zhang, Yue Lu, Prof. Aiguo Wu, Prof. Congzhong Cai and Prof. Hengwei Lin
On the dot: A facile approach to photoluminescent carbon dots (CDs) that can be excited by a single wavelength and demonstrate emission of the three primary colors (red, green, and blue) is reported. The resulting CDs can be potentially used in the fabrication of flexible full-color emission films and in multicolor cellular imaging.
B,N Azo Dyes
Formation of BN Isosteres of Azo Dyes by Ring Expansion of Boroles with Azides
Prof. Dr. Holger Braunschweig, Dr. Mehmet Ali Celik, Florian Hupp, Dr. Ivo Krummenacher and Lisa Mailänder
Azo borealis: The first 1,2-azaborinine-substituted azo dyes have been synthesized using sterically demanding boroles and organic azides. The ring-expansion mechanism of the unexpected formation of the bright yellow chromophores was investigated by DFT calculations.
Multifunctional Reagents for Quantitative Proteome-Wide Analysis of Protein Modification in Human Cells and Dynamic Profiling of Protein Lipidation During Vertebrate Development
Dr. Malgorzata Broncel, Dr. Remigiusz A. Serwa, Paulina Ciepla, Dr. Eberhard Krause, Prof. Margaret J. Dallman, Prof. Anthony I. Magee and Prof. Edward W. Tate
Catch and release: Multifunctional capture reagents were developed that enable enzymatically-triggered release and direct detection of lipid-modified peptides by mass spectrometry. Dynamic proteome lipidation was visualized, enriched, and identified on an unprecedented scale, both in cells and in a developing zebrafish embryo.
Intracellular Modulation of Excited-State Dynamics in a Chromophore Dyad: Differential Enhancement of Photocytotoxicity Targeting Cancer Cells
Dr. Safacan Kolemen, Dr. Murat Işık, Gyoung Mi Kim, Dabin Kim, Hao Geng, Muhammed Buyuktemiz, Tugce Karatas, Prof. Xian-Fu Zhang, Prof. Yavuz Dede, Prof. Juyoung Yoon and Prof. Engin U. Akkaya
Selective switch: A dimeric BODIPY dye with reduced symmetry is ineffective as a photosensitizer unless it is activated by a reaction with intracellular glutathione (GSH). Staining with red-fluorescent Annexin V shows that the photosensitizer is preferentially switched on in cancer cells, which feature a higher GSH level than normal cells.
Strained Cyclooctyne as a Molecular Platform for Construction of Multimodal Imaging Probes
Yao Sun, Dr. Xiaowei Ma, Kai Cheng, Biying Wu, Jianli Duan, Hao Chen, Lihong Bu, Ruiping Zhang, Prof. Xianming Hu, Zixin Deng, Lei Xing, Xuechuan Hong and Prof. Zhen Cheng
Spitting image: The products of the base-catalyzed addition of various functional molecules to bicyclo[6.1.0]nonyne-based scaffolds provided precursors for novel dual-modality (PET and NIRF) uPAR-targeted imaging probes. The probes were evaluated in U87MG cells and tumor-bearing mice models, thus demonstrating excellent imaging characteristics.
Controlling the Origins of Inflammation with a Photoactive Lipopeptide Immunopotentiator
Dr. Rock J. Mancini, Lalisa Stutts, Dr. Troy Moore and Prof. Aaron P. Esser-Kahn
The origin of inflammation in cell culture is commonly obscured by paracrine and autocrine signaling. A small-molecule immunopotentiator was developed that tags cells and initiates inflammation of the tagged cells using light. BMDCs=bone-marrow-derived dendritic cells, TNF=tumor necrosis factor.
Widening Synthesis Bottlenecks: Realization of Ultrafast and Continuous-Flow Synthesis of High-Silica Zeolite SSZ-13 for NOx Removal
Zhendong Liu, Prof. Dr. Toru Wakihara, Dr. Kazunori Oshima, Daisuke Nishioka, Yuusuke Hotta, Dr. Shanmugam P. Elangovan, Yutaka Yanaba, Prof. Dr. Takeshi Yoshikawa, Dr. Watcharop Chaikittisilp, Takeshi Matsuo, Takahiko Takewaki and Prof. Dr. Tatsuya Okubo
Bottle opener: SSZ-13 is a zeolite commercialized as a catalyst to remove nitrogen oxides (NOx). However, its long synthesis time is one of the biggest barriers to large-scale production. An ultrafast synthesis route now allows SSZ-13 to be synthesized in 10 min and thus facilitates continuous preparation of SSZ-13. The fast-synthesized SSZ-13 exhibits outstanding performance for the NOx removal.
Bioorthogonal Deprotection on the Dendritic Cell Surface for Chemical Control of Antigen Cross-Presentation
Joanna B. Pawlak, Geoffroy P. P. Gential, Dr. Tracy J. Ruckwardt, Jessica S. Bremmers, Nico J. Meeuwenoord, Prof. Ferry A. Ossendorp, Prof. Herman S. Overkleeft, Dr. Dmitri V. Filippov and Dr. Sander I. van Kasteren
Antigen cross-presentation is the uptake of exogenous antigens followed by processing in the MHC-I complex, which is normally reserved for endogenous antigens. This process may now be studied by using masked epitopes: Azides are exploited as bioorthogonal protecting groups to generate antigens that are not recognized by their cognate T-cell unless they are deprotected using an on-cell Staudinger reduction.
Heterogeneously Catalyzed Direct CH Thiolation of Heteroarenes
Suhelen Vásquez-Céspedes, Dr. Angélique Ferry, Dr. Lisa Candish and Prof. Dr. Frank Glorius
(Hetero)genius: A general method for the direct thiolation of electron-rich heteroarenes was developed by employing Pd/Al2O3, a recoverable and commercially available heterogeneous catalyst, and CuCl2. Preliminary mechanistic studies indicate a heterogeneous active catalytic species, with the two metals playing complementary roles in the formation of the thiolated products.
Macromolecular Surface Design: Photopatterning of Functional Stable Nitrile Oxides
Dr. Ozcan Altintas, Dr. Mathias Glassner, Dr. Cesar Rodriguez-Emmenegger, Dr. Alexander Welle, Vanessa Trouillet and Prof. Dr. Christopher Barner-Kowollik
Perfect Patterning: The cycloaddition between a photogenerated thioaldehyde and stable nitrile oxides functions as a versatile and easy-to-use photoligation reaction in solution and on surfaces as confirmed by ESI-MS, XPS, and TOF-SIMS analysis. Polymer brushes were grown from the surface in a spatially confined regime by surface-initiated atom-transfer radical polymerization.
A Promiscuous De Novo Retro-Aldolase Catalyzes Asymmetric Michael Additions via Schiff Base Intermediates
Dr. Xavier Garrabou, Dr. Tobias Beck and Prof. Dr. Donald Hilvert
Born promiscuous: Artificial enzymes obtained by computational design and directed evolution utilize relatively simple catalytic machineries to achieve remarkable levels of activity. These catalysts are potentially a rich source of novel chemical reactivity, as shown for the artificial retro-aldolase RA95.5-8, which also efficiently catalyzes asymmetric Michael additions via iminium ion intermediates.
Self-Template-Directed Synthesis of Porous Perovskite Nanowires at Room Temperature for High-Performance Visible-Light Photodetectors
Sifei Zhuo, Jingfang Zhang, Yanmei Shi, Yi Huang and Prof. Dr. Bin Zhang
In solution: Porous CH3NH3PbBr3 perovskite nanowires (PNW-CH3NH3PbBr3) were fabricated by an efficient self-template-directed synthesis using the Pb-containing precursor nanowires as both the sacrificial template and the Pb2+ source in the presence of CH3NH3Br and HBr in solution. The perovskite nanowires are potential materials for visible-light photodetectors.