The ability to incorporate functional metal ions (M n+ ) into metal‐organic coordination complexes adds remarkable flexibility in the synthesis of multifunctional organic‐inorganic hybrid materials with tailorable electronic, optical, and magnetic properties. Herein, we report the cation‐exchanged synthesis of a diversity of hollow M n+ ‐ phytate (PA) micropolyhedra via the use of hollow Co 2+ ‐PA polyhedral networks as templates at room temperature. The attributes of the incoming M n+ ,...
Wed Aug 12, 2020 11:02
Controlling the spectral tunability and isomerization activity is currently one of the hot topics in the design of photo‐reversible molecular switches for application in optoelectronic devices. The present work demonstrates how to manipulate the absorption of the retinal protonated Schiff base (rPSB) chromophore over the entire visible range by targeted functionalization of the retinal backbone. Moreover, we establish a correlation between the vertical excitation energy and the profile of the potential...
Tue Aug 11, 2020 19:53
Obtaining structures of intact redox states of metal centres derived from zero dose X‐ray crystallography can advance our mechanistic understanding of metalloenzymes. In dye‐decolourising heme peroxidases (DyPs), controversy exists regarding the mechanistic role of the distal heme residues, aspartate and arginine, in the heterolysis of peroxide to form the catalytic intermediate compound I (Fe IV =O and a porphyrin cation radical). Using serial femtosecond X‐ray (SFX) crystallography, we have...
Tue Aug 11, 2020 19:52
Ornithine is a component of many bioactive nonribosomal peptides but has been challenging to incorporate into ribosomal products. We recently identified OspR, a cyanobacterial arginase‐like enzyme that installs ornithines in the antiviral ribosomally synthesised and posttranslationally modified peptide (RiPP) landornamide A. Here we report that OspR belongs to a larger family of peptide arginases from diverse organisms and RiPP types. In E. coli expressions, seven selected enzymes converted arginine...
Tue Aug 11, 2020 19:25
A misfit compound, PbNbS3, has a soft/rigid superlattice structure. Soft PbS sublayers contribute the capacity and the rigid NbS2 sublayers maintain the stability and dominate the conductivity, thus promoting the migration of electrons and lithium ions, leading to competitive lithium‐ion anode performance. Abstract Volume expansion and poor conductivity are two major obstacles that hinder the pursuit of the lithium‐ion batteries with long cycling life and high power density. Herein, we...
Tue Aug 11, 2020 19:23
By fusing aza‐aromatics onto a B−N skeleton, a hybridized multi‐resonance charge‐transfer molecule AZA‐BN was synthesized. The AZA‐BN device exhibits narrow‐band green electroluminescence with maximum external quantum efficiency/CIE coordinate y of 28.2 %/0.69, representing the purest green bottom‐emitting organic light‐emitting diode. Abstract Pure green emitters are essential for realizing an ultrawide color gamut in next‐generation displays. Herein, by fusing the difficult‐to‐access...
Tue Aug 11, 2020 19:22
Icing experiments performed on surfaces of pyroelectric crystals discover that heterogeneous electrofreezing is a chemical process promoted by planar trigonal HCO3 −, NO3 − and guanidinium+ ions. Abstract Electrofreezing experiments of super‐cooled water (SCW) with different ions, performed directly on the charged hemihedral faces of pyroelectric LiTaO3 and AgI crystals, in the presence and in the absence of pyroelectric charge are reported. It is demonstrated that bicarbonate (HCO3...
Tue Aug 11, 2020 19:22
Ruthenium‐mediated cycloaromatization reactions engaging three alkyne units can be performed in intracellular settings in a biocompatible way. This synthetically powerful reaction allows access to a variety of relatively complex, functional cyclic products inside cells, therefore providing an artificial metabolic route to these interesting species. Abstract Metal‐mediated intracellular reactions are becoming invaluable tools in chemical and cell biology, and hold promise for strongly impacting...
Tue Aug 11, 2020 19:22
Dilution of Pd/TiO2 with neat TiO2 results in the formation of atomically dispersed Pd under reverse water–gas shift (rWGS) reaction conditions at 400 °C and a several fold increase in activity. Abstract The application of single‐atom catalysts (SACs) to high‐temperature hydrogenation requires materials that thermodynamically favor metal atom isolation over cluster formation. We demonstrate that Pd can be predominantly dispersed as isolated atoms onto TiO2 during the reverse water–gas shift...
Tue Aug 11, 2020 19:19
A composition tuning strategy is employed to develop a group of ANNi3 antiperovskite nitrides (A=In or Cu). By partial substitution of the A site in the pristine antiperovskite nitride, a remarkable enhancement of the hydrogen evolution reaction (HER) performance is achieve on the derived Cu x In1−x NNi3 electrocatalysts. This is ascribed to the lowered kinetic barrier and optimal hydrogen adsorption free energy by the compositional adjustment. Abstract A group of newly reported...
Tue Aug 11, 2020 19:19
A co‐assembled vaccine, composed of lipidated antigens and lipophilic adjuvants, is reported. This vaccine design possesses both antigen multivalency and antigen‐specific immunostimulation properties, and induces a robust immune response. This simple vaccine initiated a potent immune response without requiring complex synthesis, allowing efficient and practical development of self‐adjuvanting vaccines. Abstract Co‐assembling vaccines composed of a lipidated HER2‐derived antigenic CH401...
Tue Aug 11, 2020 19:18
The first examples of homochiral dabco‐based (dabco=1,4‐diazabicyclo[2.2.2]octane) ferroelectrics, [R and S‐2‐Me‐H2dabco][TFSA]2 (TFSA=bis(trifluoromethylsulfonyl)ammonium), were designed from the non‐ferroelectric [H2dabco][TFSA]2. They show two phase transitions with a transition temperature (T c) up to 405.8 K and 415.8 K, higher than the T c of most dabco‐based or homochiral ferroelectrics. Abstract 1,4‐Diazabicyclo[2.2.2]octane (dabco) and its derivatives have been extensively...
Tue Aug 11, 2020 19:18
Photoelectric and photocatalytic effects endow the covalent organic framework NDA‐TN‐AO with good anti‐biofouling activity. This occurs by generating biotoxic reactive oxygen species and promoting photoelectrons to reduce the adsorbed UVI to insoluble UIV, thereby improving the uranium adsorption capacity. Abstract Uranium is a key resource for the development of the nuclear industry, and extracting uranium from the natural seawater is one of the most promising ways to address the shortage...
Tue Aug 11, 2020 19:18
Thermally induced cyclodehydrofluorization of a tetraphenylporphyrin proceeded with high stereoselectivity on a gold surface in an ultrahigh vacuum to give the prochiral windmill product (see scheme), which aggregated into a two‐dimensional conglomerate. Such surface topochemistry enabled by alignment and dense packing may offer new possibilities for stereoselective synthesis in other systems. Abstract The thermally induced cyclodehydrofluorization of iron tetrakis(pentafluorophenyl)porphyrin...
Tue Aug 11, 2020 19:14
A simple and practicable strategy is established to obtain high‐contrast reversible mechanoresponsive PL switching by introducing a volatile third party into the lattice of mixed‐stacking CT cocrystal. This has the purpose of constructing the loosely packing mode to realize a facile control of molecular assemblies and CT excitons in the solid state. Abstract A practicable strategy to rationally obtain the reversible mechanochromic luminescent (MCL) material with high‐contrast ratio (green...
Tue Aug 11, 2020 19:10
By switching the reactivity of Pd‐containing dipolar intermediates from all‐carbon 1,3‐dipoles to oxo‐1,5‐dipoles, Pd‐catalyzed asymmetric [5+2] cycloadditions of vinylcyclopropanes (VCPs) with photogenerated ketenes is achieved. A variety of chiral seven‐membered lactone‐fused polycyclic molecules are produced with good reaction efficiency and selectivity. Abstract Vinylcyclopropanes (VCPs) are commonly used in transition‐metal‐catalyzed cycloadditions, and the utilization of their recently...
Tue Aug 11, 2020 19:09
Large or small (ring), that was the question . The antibiotic disciformycin B has been synthesized in 18 linear steps from simple starting materials. The key step was the macrocyclization of the tetraene 7 by ring‐closing olefin metathesis (RCM). Abstract The total synthesis of the potent new antibiotic disciformycin B (2 ) is described, which shows significant activity against methicillin‐ and vancomycin‐resistant Staphylococcus aureus (MRSA/VRSA) strains. The synthetic route is based...
Tue Aug 11, 2020 19:09
Going for gold : A building‐block exchange strategy gave an irreversible amide‐linked covalent organic framework (COF). The irreversible‐amide linked COF gave good stability, unprecedented fast adsorption kinetics, excellent selectivity and outstanding adsorption capacity for gold recovery. Abstract Design of stable adsorbents for selective gold recovery with large capacity and fast adsorption kinetics is of great challenge, but significant for the economy and the environment. Herein, we...
Tue Aug 11, 2020 19:09
Tumor microenvironment and metabolism regulation can be achieved by targeting carbonic anhydrase IX with platinum(IV) prodrugs, termed CAIXplatins. This strategy could be used to treat hypoxic and aggressive tumors. The advantages of CAIXplatins in comparison to cisplatin/oxaliplatin include the greatly increased cancer selectivity index, enhanced therapeutic efficiency, reduced level of side‐effects, as well as the excellent anti‐angiogenesis activity. Abstract Hypoxia and the acidic microenvironment...
Tue Aug 11, 2020 19:09
Crystallization‐induced emission of a di‐boron complex luminophore, which gives blue‐shifted and enhanced photoluminescence and electrochemiluminescence (ECL) in the annihilation pathway, is reported. ECL at crystalline film/solution interfaces was further enhanced by means of both co‐reactant route and restriction of intramolecular rotation. Abstract Elucidating the effects of crystallization‐induced blue‐shift emission of a newly synthesized di‐boron complex (DBC) by enhanced photoluminescence...
Tue Aug 11, 2020 19:09
Connecting parts of a resorcin[4]arene derivative through stepwise intramolecular acylation, reduction, and intramolecular acylation reactions produces a diketone‐bearing zigzag hydrocarbon belt. Further chemical modifications result in the formation of diverse functional molecules with different belt structures. Abstract Described in this paper are the synthesis and structure of novel and edge‐functionalized zigzag hydrocarbon belts. A stepwise “fjord‐stitching” strategy featuring repetitive...
Tue Aug 11, 2020 19:08
Enantioselective syntheses of strychnos and chelidonium alkaloids were achieved via the regio and stereocontrolled synthesis of homoallylic amines through isothiourea/transition‐metal cooperative catalysis. Indole acetic acid esters were established as remarkably effective nucleophiles, enabling syntheses of akuammicine, strychnine, and an SIRT‐1 inhibitor. Structure‐based reactivity challenges were overcome to synthesize three chelidonium alkaloids. Abstract We describe enantioselective...
Tue Aug 11, 2020 19:08
A periodically ordered nick‐hidden DNA nanowire composed of six distinct oligonucleotide components was developed as a powerful drug‐delivery vehicle for the accurate diagnosis and targeted therapy of cancers (see picture). Owing to the high serum stability and active targeting functionality of the construct, NWs loaded with doxorubicin exhibited a long blood‐circulation time and high specificity in inducing cancer‐cell apoptosis. Abstract DNA nanostructures have shown potential in cancer...
Tue Aug 11, 2020 19:07
Better off alone : A nanoreactor approach was used to investigate the chemistry of 2‐cyanobenzothiazole (CBT), an important bioorthogonal reagent, at the single‐molecule level. Reactions with thiols and aminothiols revealed mechanistic and kinetic information with important implications for several essential applications of CBT reagents. Abstract We report a single‐molecule mechanistic investigation into 2‐cyanobenzothiazole (CBT) chemistry within a protein nanoreactor. When simple thiols...
Tue Aug 11, 2020 19:07
A semi‐immobilization strategy is proposed for redox mediator (RM) design to effectively regulate the sulfur electrochemistry whilst circumventing the inherent shuttle issue in a working lithium sulfur battery. Small imide molecules as the model RMs were co‐polymerized with moderate‐chained polyether, rendering a semi‐immobilized RM (PIPE) that is spatially restrained in the cathode yet kinetically active. Abstract Use of redox mediators (RMs) is an effective strategy to enhance reaction...
Tue Aug 11, 2020 19:06
A two‐step, one‐pot chemoenzymatic synthesis of chiral anilines is reported. Chiral‐amine‐producing biocatalysts have been combined in the same pot as a Pd catalyst to allow the direct conversion of prochiral and racemic starting materials to enantiopure anilines. The use of a surfactant to enable this one‐pot process is a first for biocatalysis. Abstract The combination of biocatalysis and chemo‐catalysis increasingly offers chemists access to more diverse chemical architectures. Here,...
Tue Aug 11, 2020 19:06
A photocatalytic strategy for the vicinal aminopyridylation of ketones was developed using pyridinium N−N ylides as bifunctional reagents. Intriguingly, the synthetic advances of this approach were highlighted by the selective installation of amino and pyridyl groups into the nucleophilic α‐position and electrophilic carbonyl carbon, respectively. Abstract A photocatalytic double umpolung strategy for the vicinal aminopyridylation of ketones was developed using pyridinium N−N ylides. The...
Tue Aug 11, 2020 18:55
Reported here is a mitochondria‐targeted ReI complex, DFX‐Re3 , that can relocate iron to the mitochondria and change the metabolites related to epigenetics. DFX‐Re3 can elevate the methylation levels of histone/DNA/RNA, affect RNA polymerase activities, and induce immunogenic apoptosis. This study provides a new approach to the design of epigenetic drugs for recoding the cancer epigenome by intervening in mitochondrial metabolism and iron homeostasis. Abstract The development and malignancy...
Tue Aug 11, 2020 18:55
Insertion into unactivated C(sp3)−H bonds by metal carbenes/carbenoids is a reaction of significant synthetic value. In this study, easily accessible alkynone substrates are converted into strained cyclobutanones through such an insertion by an oxidatively generated β‐diketone‐α‐gold carbene. This reaction serves as a benign and more synthetically expedient alternative to diazo‐based approaches. Abstract Cyclobutanones are synthetically versatile compounds that often require extensive...
Tue Aug 11, 2020 18:54
Ni2Mo3N performs excellently in the oxygen evolution reaction, outperforming the benchmark catalyst RuO2. This stems from a surface‐oxide‐rich activation layer (SOAL) where Ni atoms are the active sites and Mo atoms can be considered as an electron pump to transfer surface charges, stabilize the oxygen‐contained product species, and facilitate the continuity of the oxygen reactions. Abstract The oxygen evolution reaction (OER) is key to renewable energy technologies such as water electrolysis...
Tue Aug 11, 2020 18:54
DNA‐based affinity labeling probes enabled the capture and characterization of HDAC‐associated proteins, including direct and indirect binders in HDAC complexes. This method provides a simple and broadly applicable chemical tool to study protein–protein interactions. Abstract Histone deacetylase (HDAC) is a major class of deacetylation enzymes. Many HDACs exist in large protein complexes in cells and their functions strongly depend on the complex composition. The identification of HDAC‐associated...
Tue Aug 11, 2020 18:53
Formal platinum(III) complexes obtained after collisional activation of PtIV prodrugs are assayed using IR ion spectroscopy to identify vibrational features characteristic of their electronic structure. The role of the non‐innocent NH2 ligand in the formation of these elusive PtIII complexes is discussed on the basis of spin natural orbital analyses. Abstract Platinum(IV) complexes are extensively studied for their activity against cancer cells as potential substitutes for the widely used...
Tue Aug 11, 2020 18:48
By simultaneously engineering molecular geometry and nanocrystal wavefunction, energy transfer and photon upconversion efficiencies of a perovskite nanocrystal/molecule system can be improved by orders of magnitude. Abstract Triplet energy transfer from inorganic nanocrystals to molecular acceptors has attracted strong attention for high‐efficiency photon upconversion. Here we study this problem using CsPbBr3 and CdSe nanocrystals as triplet donors and carboxylated anthracene isomers as...
Tue Aug 11, 2020 18:48
In recent years, multiple catalytic C−H functionalization has emerged as an efficient strategy to synthesize complex natural products in a concise manner from easily accessible precursors. This Minireview presents recent examples where this strategy is employed in the context of both linear and convergent syntheses. Abstract In the past decade, multiple catalytic C−H bond functionalization has been successfully applied in natural product synthesis as a strategy to reduce the number of steps,...
Tue Aug 11, 2020 18:48
The development of fluorophores for the second near‐infrared window (NIR‐II, 1000 ‐ 1700 nm) represents a newly emerging, significant and vibrant field in analytic chemistry, chemical biology and biomedical engineering. The wavelength, brightness, and stability are three crucial factors that determine the performance of a NIR‐II fluorophore. Up to now, significant progress has been made in the development of NIR‐II fluorescence molecular probes, including the synthesis of D‐A‐D and D‐π‐A fluorophores...
Tue Aug 11, 2020 16:51
Propagation of homochirality plays a crucial role in the discussion on the origin of life. We here investigate the role of structurally related enantiopure additives in chiral symmetry breaking during reactive crystallizations. We demonstrate that a symmetry breaking process can be driven towards the same absolute configuration as the additive if this additive forms an enantiospecific solid solution with the racemate. We observe two antagonistic processes: enantiospecific growth inhibition directs...
Tue Aug 11, 2020 16:50
Sun‐light driven water splitting to produce hydrogen and oxygen gases in a large scale is a promising method for solar energy conversion. However, it is still a challenge to explore photocatalytic materials for overall water splitting due to the limited choice of a single semiconductor with suitable band energy levels (matching with water redox splitting potentials) while with minimized band gap for light harvesting. Here, we report a one‐photon excitation pathway by coupling polymeric carbon nitride...
Tue Aug 11, 2020 16:44
Mono‐coordinated silicon(II) cations are predicted to be reactive ambiphiles, combining the typically high Lewis acidity of silicon cations with nucleophilicity due to the presence of an electron pair at the same atomic centre. Here, a carbazole‐derived scaffold was used to isolate salts with a mono‐coordinated silicon(II) cation, [RSi]+ (R = bulky carbazolyl substituent), by halide abstraction from a base‐free halosilylene, RSiI, with the Ag[Al(O t BuF)4]. Despite the bulk of the carbazolyl moiety,...
Tue Aug 11, 2020 12:18
The degradation and repair of uniform sequence‐defined poly( N ‐substituted urethanes) was studied. Polymers containing an ω‐OH end‐group and only ethyl carbamate main‐chain repeat units rapidly degrade in NaOH solution via an ω→α depolymerization mechanism with no apparent sign of random chain cleavage. The degradation mechanism is not notably affected by the nature of the side‐chain N ‐substituents and took place for all studied sequences. On the other hand, depolymerization is significantly...
Tue Aug 11, 2020 12:15
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