We report on the directed postsynthetic functionalization of soft DNA nanocomposite materials with proteins. Using the example of the functionalization of silica nanoparticle‐modified DNA polymer materials with agonists or antagonists of the epidermal growth factor receptor EGFR cell membrane receptor, we demonstrate that hierarchically structured interfaces to living cells can be established. Due to the modular design principle, even complex DNA nanostructures can also be integrated into the materials,...
Sat Jul 18, 2020 14:29
RNA‐cleaving deoxyribozymes can serve as selective sensors and catalysts to examine the modification state of RNA. However, site‐specific endonuclease deoxyribozymes that selectively cleave posttranscriptionally modified RNA are extremely rare and their specificity over unmodified RNA is low. In this study, we report that the native tRNA modification N 6 ‐isopentenyladenosine (i 6 A) strongly enhances the specificity and has the power to reconfigure the active site of an RNA‐cleaving deoxyribozyme....
Sat Jul 18, 2020 12:28
The current energy transition presents many technological challenges, such as the development of highly stable catalysts. Herein, we report a novel “top‐down” synthesis approach for preparation of a single‐site Mo‐containing nanosized ZSM‐5 zeolite possessing atomically dispersed framework‐molybdenum homogenously distributed through the zeolite crystals. The introduction of Mo heals most of the native point defects in the zeolite structure resulting in an extremely stable material. The important...
Sat Jul 18, 2020 11:28
Nanoparticles have been widely investigated for preclinical animal models as imaging, therapeutic or theranostic agent. However, a very limited number of nanoscale materials are approved for human use due to retention and toxicity concerns. Recent years have seen in vivo fluorescence imaging in the long end of the second near infrared window (NIR‐IIb, 1,500‐1,700 nm), affording deeper tissue penetration and higher imaging clarity owing to reduced light scattering and near‐zero autofluorescence. Most...
Sat Jul 18, 2020 11:27
We developed a direct mapping approach to overlay the image of a polycrystalline perovskite film obtained from the transient absorption microscope (TAM) with that from the scanning electron microscope (SEM). By mapping these imaging data pixel by pixel, we are able to observe the relaxation dynamics of the photo‐generated charge carriers on varied regions of the film. The carrier relaxation dynamics contain a dominated single‐exponential decay component due to the recombination of charge carriers....
Fri Jul 17, 2020 20:29
The discovery of chemical methods enabling the construction of carbocycle‐fused uracils which embody a three‐dimensional and functional group‐rich architecture is a useful tool in medchem synthesis. In this work, an unprecedented amine‐catalyzed [4 + 2] cross cycloaddition is documented, which involved remotely enolizable 6‐methyluracil‐5‐carbaldehydes and β‐aryl enals, and chemoselectively produced two novel bicyclic and tricyclic fused uracil chemotypes in good yields and maximum level of enantiocontrol....
Fri Jul 17, 2020 19:01
Abstract: Designing deep‐Ultraviolet (DUV) nonlinear optical (NLO) crystals is of the current research interests but faces a great challenge. In order to overcome the problem of crystal growth and the toxicity of BeO raw materials in KBe2BO3F2 (KBBF), the only applicable DUV NLO crystal so far, we substitute Be2+ cations with Zn2+ in the KBBF structure and modify the halogen anions, by which three new Zn‐containing KBBF‐like compounds, CsZn2BO3X2 (X = F, Cl and F&Cl), have been successfully synthesized....
Fri Jul 17, 2020 17:29
A highly enantioselective synthesis of various chiral heterobicyclic molecules including spiroaminals and fused bicyclic acetals has been developed via a chiral copper catalyzed cyclopropanation–rearrangement (CP‐RA) approach under mild reaction conditions. Remarkably, the asymmetric CP‐RA for exocyclic vinyl substrates without a pro‐stereogenic carbon at the β‐positionhas been realized for the first time, and thus broad substrate scope with excellent results (33 examples; 34‐99% yields; >95/5...
Fri Jul 17, 2020 14:34
Developing novel two‐dimensional (2D) and single atomic layered materials is a fascinating challenge. Here we successfully synthesize porphyrin‐based monoatomic layer (PML), a freestanding 2D porphyrin‐based material of monomer‐unit thickness (2.8 Å). The solvothermal method provides a bottom‐up approach for tailoring the monoatomic layer from the nanoscale to the milliscale. PMLs containing accurately tailorable M–N4 units (M=Cu and Au) were synthesized, which present metal center‐dependent performance...
Fri Jul 17, 2020 12:59
The description of substituents as electron donating or withdrawing leads to a perceived dominance of through‐bond influences. The situation is compounded by the challenge of separating through‐bond and through‐space contributions. Measurements of through‐space substituent effects question classic descriptions of substituent effects. Abstract The description of substituents as electron donating or withdrawing leads to a perceived dominance of through‐bond influences. The situation is compounded...
Fri Jul 17, 2020 12:19
Ordered assembly of molecules within a specific space of nanoscale, such as surface, holds great promise in advanced micro‐/nanostructure fabrication for various applications. Herein, we demonstrated the evanescent wave (EW)‐guided organization of small molecules into long‐range ordered nanowire (NW) array. Experiment and simulation revealed that the orientation and periodicity of the NW array were feasibly regulated by altering the propagation direction and the wavelength of EW, respectively. The...
Fri Jul 17, 2020 11:00
Metallaphotoredox catalysis has evolved into an enabling platform to construct C(sp3)‐hybridized centers under remarkably mild reaction conditions. The cultivation of abundant radical precursor feedstocks has significantly increased the scope of transition‐metal‐catalyzed cross‐couplings, especially with respect to C(sp2)–C(sp3) linkages. In recent years, considerable effort has been devoted to understanding the origin of stereoinduction in dual catalytic processes. In this context, Ni‐ and Cu‐catalyzed...
Fri Jul 17, 2020 10:50
Electrocatalytic CO2 reduction to value‐added products provides a viable alternative to the use of carbon sources derived from fossil fuels. Nevertheless, the ability to carry out these transformations at reasonable energetic costs, e.g. with low overpotential, remains a significant challenge. Molecular catalysts offer a great option in this context, as fine control of their activity and selectivity can be obtained via the tuning of their coordination sphere and ligand set. To this end, we investigated...
Thu Jul 16, 2020 22:59
A Redox‐active Heterobimetallic N‐heterocyclic Carbene Based on a Bis(imino)pyrazine Ligand Scaffold
A new redox‐active N‐heterocyclic carbene (NHC) architecture is obtained using N‐methylated pyrazinediimine iron complexes as precursors. The new species exhibit strong π‐accepting/σ‐donating properties and are able to ligate two metal centres simultaneously. The redox activity was demonstrated by the reversible chemical oxidation of a heterobimetallic Fe 0 /Rh I example, which affords an isolable ligand‐based radical cation. The reversible redox process was then applied in the catalytic hydrosilylation...
Thu Jul 16, 2020 22:00
Although numerous theoretic approaches have been developed for predicting aqueous p K a , fast and accurate prediction of non‐aqueous p K a s has remained a major challenge. On the basis of iBonD experimental p K a database curated across 39 solvents, a holistic p K a prediction model was established by using machine learning approach. Structural and physical organic parameters combined descriptors (SPOC) were introduced to represent the electronic and structural features of molecules....
Thu Jul 16, 2020 20:23
Historically, researchers have put considerable effort into developing automation systems to prepare natural biopolymers such as peptides and oligonucleotides. The availability of such mature systems has significantly advanced the development of natural science. Over the past twenty years, breakthroughs about automation synthesis of oligosaccharides have also been made. Herein, we described a machine‐driven platform for glycopeptide synthesis by a reconstructed peptide synthesizer. The designed platform...
Thu Jul 16, 2020 18:29
Lolitrems are tremorgenic indole diterpenes that exhibit a unique 5/6 bicyclic system of the indole moiety. Although genetic analysis has indicated that prenyltransferase LtmE and cytochrome P450 LtmJ are involved in the construction of this unique structure, the detailed mechanism remains to be elucidated. Herein, we reconstitute the biosynthetic pathway for lolitrems employing a recently established genome‐editing technique for the expression host Aspergillus oryzae. Heterologous expression and...
Thu Jul 16, 2020 17:00
Lewis base catalyzed kinetic resolution of acyclic tertiary alcohols was achieved with selectivity factors of up to 200. Enantiodiscrimination is proposed to be reliant on the alcohol substrate containing a carbonyl recognition motif. The method, which tolerates aryl, heteroaryl, vinyl, alkyl substituents, and was also translated to continuous flow using a solid‐supported variant of the catalyst. Abstract A highly enantioselective isothiourea‐catalyzed acylative kinetic resolution (KR)...
Thu Jul 16, 2020 14:27
Catalysts in action : Scanning electrochemical microscopy was used to quantitatively analyze O2 reductive activation in organic media catalyzed by three different Fe porphyrins. In one single experiment the redox potential of various intermediates, the association constant of FeII with O2, and the pKa of the FeIII(OOH−)/ FeIII(OO2−) couple can be determined. Abstract Herein we report the first example of using scanning electrochemical microscopy (SECM) to quantitatively analyze O2 reductive...
Thu Jul 16, 2020 14:23
While half‐reactions using organic photocatalysts for hydrogen production are encouraging, systems with high efficiency without using sacrificing electron donors (SED) and showing full overall water‐splitting are still largely absent. Critical factors that are limiting the overall water‐splitting using organic photocatalysts are summarized, with a supplementary discussion on remaining challenges. Abstract In pursuit of inexpensive and earth abundant photocatalysts for solar hydrogen production...
Thu Jul 16, 2020 14:20
A trans ‐selective alkyne cyanoboration debuts! A Pd complex supported by an 1,4‐azaborine‐derived phosphine ligand is uniquely capable to transform 1,3‐enynes into tetra‐substituted borylated dienenitriles with high site‐, regio‐, and trans‐diastereoselectivity. Abstract The first trans‐selective cyanoboration reaction of an alkyne, specifically a 1,3‐enyne, is described. The reported palladium‐catalyzed cyanoboration of 1,3‐enynes is site‐, regio‐, and diastereoselective,...
Thu Jul 16, 2020 14:20
A matter of concentration : The latest ground‐breaking advances and strategies of using concentrated electrolyte for aqueous batteries, are discussed. Emphasis is placed on aqueous batteries for lithium and post‐lithium chemistries, with improved energy density, resulting from the unique properties of salt‐concentrated electrolytes. Abstract Aqueous rechargeable batteries are becoming increasingly important to the development of renewable energy sources, because they promise to meet cost‐efficiency,...
Thu Jul 16, 2020 14:19
Take your PIC : Polyimidazolium cages (PICs) are used as templates to synthesize and stabilize catalytically active, cavity‐hosted, dispersed poly‐N‐heterocyclic carbene (NHC)‐anchored gold nanoparticles NPs. The resulting Au NPs display impressive thermal and chemical stability and high catalytic activities. Abstract Controlling the size and surface functionalization of nanoparticles (NPs) can lead to improved properties and applicability. Herein, we demonstrate the efficiency of the metal‐carbene...
Thu Jul 16, 2020 14:19
RuII complexes were developed to act as dual catalytic inhibitors of topoisomerase I and II. Tuning of the auxiliary ligands gave complex Ru7 , which targets the nucleus of cancer cells effectively, inducing cell death via necroptosis. The cell signaling pathways were investigated and the in vivo activity against drug resistant cancer was found to be excellent. Abstract Inducing necroptosis in cancer cells is an effective approach to circumvent drug‐resistance. Metal‐based triggers have,...
Thu Jul 16, 2020 14:19
Flexible and radical : 9,10‐bis(phenylethynyl)anthracene radical cation (BPEA.+ ) crystals obtained by electrocrystallization showed high electrical conductivity and are flexible. Their flexibility is a result of close packing and the help of the hydrogen bonding of the electrolyte anions which allows them to act as mechanical ball‐bearings. Abstract Together with high conductivity, high flexibility is an important property required for next generation organic electronic components. Both...
Thu Jul 16, 2020 14:19
Two‐in‐one : A (MeDalphos)AuCl complex promotes both oxidative addition of aryl iodides and π‐activation of alkenols/alkenamines. The reaction is robust and general (>30 examples including internal alkenes, 5‐, 6‐, and 7‐membered rings). It is regioselective and leads exclusively to trans addition products. Abstract Heteroarylation of alkenes with aryl iodides was efficiently achieved with a (MeDalphos)AuCl complex through AuI/AuIII catalysis. The possibility to combine oxidative addition...
Thu Jul 16, 2020 14:16
“My biggest motivation is to make a creative and significant contribution in several research fields … My favorite saying is to try our best without regret .” Find out more about Bin Tan in his Author Profile.
Thu Jul 16, 2020 14:16
Teamwork : TiO2 decorated with both platinum nanoparticles and CuO x clusters enabled photocatalytic oxidative coupling of methane in a flow system at room temperature and atmospheric pressure with a high yield rate of 6.8 μmol h−1 for the selective synthesis of C2 hydrocarbons. It is proposed that Pt functions as an electron acceptor to facilitate charge separation, while holes may transfer to CuOx to avoid deep dehydrogenation and overoxidation (see picture). Abstract Oxidative...
Thu Jul 16, 2020 14:16
The creation of new chiral ligands capable of providing high stereocontrol in metal‐catalyzed reactions is crucial in modern organic synthesis. The production of bioactive molecules as single enantiomers is increasingly required, and asymmetric catalysis with metal complexes constitutes one of the most efficient synthetic strategies to access optically active compounds. Herein we offer a historical overview on the development of chiral derivatives of the ubiquitous cyclopentadienyl ligand (Cp X...
Thu Jul 16, 2020 13:04
Building bridges : An interfacial bridged organic–inorganic (Nafion‐Zn‐X) protection layer is developed by complexing inorganic Zn‐X zeolite nanoparticles with Nafion, which shift the ion transport from channel transport (Nafion) to hopping transport in the organic–inorganic interface. This structure suppresses dendrite formation and side reactions to guarantee the long cycle life of the Zn anode in aqueous batteries. Abstract Aqueous zinc (Zn) batteries (AZBs) are widely considered as...
Thu Jul 16, 2020 12:36
A sea of expanding shapes : A combined experimental–computational approach enabled the synthesis of low‐symmetry imine cages from mixtures of tetraaldehyde building blocks. This “social self‐sorting” approach was applied to obtain a family of new cages containing heteroatoms, showing that pores of varying geometries and surface chemistries may be reliably accessed. Abstract Many interesting target guest molecules have low symmetry, yet most methods for synthesising hosts result in highly...
Thu Jul 16, 2020 12:35
By developing a new generation of pantetheine analogue probes, the metabolic labelling and chemoproteomic profiling of protein 4′‐phosphopantetheinylation in mammalian cells were achieved. Targeted chemical proteomics facilitated the identification of exact 4′‐phosphopantetheinylation sites, including all five currently known sites and a potential site in the mitochondrial dehydrogenase/reductase SDR family member 2 (DHRS2). Abstract Protein 4′‐phosphopantetheinylation is an essential...
Thu Jul 16, 2020 12:34
The ring cycle : Using the coordination delayed hydrolysis (CDH) strategy, a new family of aluminum molecular rings ranging from 8R to 16R is assembled. The monohydric alcohols used play a crucial role in the expansion of the rings. It is possible to tune the surface chemistry and properties through the judicious choice of functional groups of benzoate ligands. Abstract Presented herein are the AlIII molecular ring architectures from 8‐ring to 16‐ring. Although there are numerous reported...
Thu Jul 16, 2020 12:34
A chiral diene–rhodium complex was found to catalyze the reaction of 1,6‐enynes with ArZnCl to give high yields of 2‐(alkylidene)cyclopentylmethylzincs with high enantioselectivity (95–99% ee). The enantioenriched alkylzincs were readily converted in one‐pot into a wide variety of functionalized products by taking advantages of their unique reactivity. The catalytic cylcle involves arylrhodation of alkyne, intramolecular alkenylrhodation of alkene, and transmetalation of the alkyl‐rhodium intermediate...
Thu Jul 16, 2020 11:01
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