A bioelectrochemical flow system has been developed to power enzymatic cascades in vitro. H2 and O2 are generated by electrolysis and serve as electron mediators for oxidoreductases. Methylated N‐heterocycles were generated from diamines with up to 99 % product formation and a labeling regioselectivity of up to 99 %. Abstract We have developed a scalable platform that employs electrolysis for an in vitro synthetic enzymatic cascade in a continuous flow reactor. Both H2 and O2 were produced...
Tue Apr 28, 2020 16:02
Metal–inorganic frameworks Hf4N20⋅N2, WN8⋅N2 and Os5N28⋅N2 built of transition metals and polymeric nitrogen linkers were synthesized by M. Bykov et al. in a one‐step synthesis from elements at high‐pressure conditions (DOI: https://doi.org/10.1002/anie.20200248710.1002/anie.202002487). The channel‐type pores are filled with ordered one‐dimensional arrays of nitrogen molecules. Due to the conjugated π‐systems of nitrogen chains these inorganic polymers are conductive materials.
Tue Apr 28, 2020 16:02
Simultaneous delivery of tobramycin and alkylquinolone inhibitors by a self‐assembling nanoparticle system based on squalenyl hydrogen sulfate (SqNPs) is an optimal therapeutic against P. aeruginosa biofilm infections. As described by C.‐M. Lehr et al. in their Communication (DOI: https://doi.org/10.1002/anie.20200140710.1002/anie.202001407), the drug‐loaded SqNPs show improved biofilm penetration and enhanced efficacy in relevant biological barriers (mucin/human tracheal mucus, biofilm), leading...
Tue Apr 28, 2020 16:01
Platinum is king! A responsive‐at‐metal platinum(II) emitter undergoes supramolecular and redox transformations on demand, as demonstrated by M. J. MacLachlan et al. in their Communication (DOI: https://doi.org/10.1002/anie.20200264610.1002/anie.202002646). PtII selectively oxidizes into PtIII or PtIV, thus diversifying the structural and photophysical properties of the emitter. Delicate modulation of Pt⋅⋅⋅Pt interactions by solvent molecules results in strong vapo/solvatochromic effects.
Tue Apr 28, 2020 16:01
Electrical energy powers an artificial enzymatic cascade in a continuous flow reactor. As reported in their Communiation (DOI: https://doi.org/10.1002/anie.20200130210.1002/anie.202001302), L. Lauterbach et al. combined electrolysis in a scalable platform with a H2‐ and O2‐dependent enzymatic cascade and separated both systems with a gas‐permeable membrane. The synthesis of N‐heterocycles from diamines is demonstrated with up to 99 % product formation along with excellent regioselective labeling...
Tue Apr 28, 2020 15:57
“My favorite quote is ‘All models are wrong, but some are useful’ … I advise my students to read first and then go to the lab (can save months of work) …” Find out more about Tom Grossmann in his Author Profile.
Tue Apr 28, 2020 15:55
Precise separation and localization of microdroplets are fundamental for various fields such as biological screening, combinatorial analysis, and complex sample recognition. In their Research Article (DOI: https://doi.org/10.1002/anie.20200383910.1002/anie.202003839), M. Li, Q. Li, Y. Song et al. demonstrate a droplet self‐splitting strategy to generate mutually‐independent microdroplets with well‐defined morphology and arrangement, and realize simultaneous multiple detections of complex analytes...
Tue Apr 28, 2020 15:55
Synergistic oxide in carbon: Bismuth oxides encapsulated in nanocarbons synergistically promotes the fast and selective CO2 conversion into formate. Abstract Carbon dioxide (CO2) conversion is promising in alleviating the excessive CO2 level and simultaneously producing valuables. This work reports the preparation of carbon nanorods encapsulated bismuth oxides for the efficient CO2 electroconversion toward formate production. This resultant catalyst exhibits a small onset potential of −0.28 V...
Tue Apr 28, 2020 15:55
Illuminating bacterial pathogens by a specific lanthanide luminescent turn‐on probe is demonstrated by H.‐Y. Hu, M. Nazaré et al. in their Communication (DOI: https://doi.org/10.1002/anie.20200239110.1002/anie.202002391). A non‐fluorescent caged precursor is intracellularly activated by bacterial nitroreductase (NTR) forming a sensitizing, light‐harvesting antenna. Entrapment of the probe inside bacterial cells allows for precise localization of live bacteria by fluorescence lifetime imaging. ...
Tue Apr 28, 2020 15:54
Time‐resolved impulsive stimulated Raman spectroscopy, which is an ultrafast time‐domain Raman technique, facilitates capturing vibrational snapshots of the excited state molecules with high sensitivity and time resolution. By using this technique, D. Kim et al. demonstrate in their Research Artible (DOI: https://doi.org/10.1002/anie.20200273310.1002/anie.202002733) that structural symmetry breaking is an important prerequisite for a charge separation reaction in a donor–acceptor–donor perylene bisimide....
Tue Apr 28, 2020 15:54
Photoinduced electrochemiluminescence (PECL) combines semiconductor (SC) photoelectrochemistry with electrochemiluminescence (ECL). In PECL, the incident light is converted to a different wavelength by an electrochemical reaction at a SC photoelectrode and allows to trigger ECL at unprecedented low potentials. This concept has been employed so far to design up‐conversion systems using Si or III‐V SCs. Nevertheless, PECL strongly suffers from the photoelectrochemical instability of these low bandgap...
Tue Apr 28, 2020 15:34
Marine dinoflagellates produce remarkable organic molecules, particularly those with polyoxygenated long carbon‐chain backbones, namely super‐carbon‐chain compounds (SCCCs), characterized by the presence of numerous stereogenic carbon centers on acyclic polyol carbon chains. Even today, it is of a great challenge to determine the absolute configurations of these compounds. In this work, the planar structures and absolute configurations of two highly flexible SCCCs, featuring a C 69 ‐ or C 71...
Tue Apr 28, 2020 12:58
The chemical ligation of two unprotected peptides to generate a natural peptidic linkage specifically at the C ‐ and N ‐termini is a challenging but desirable platform for protein chemical synthesis, as it demands high reactivity and selectivities (chemo‐, regio‐ and stereoselectivity). Here, we report an operationally simple and highly effective chemical peptide ligation involving peptides with C ‐terminal salicylaldehyde esters to ligate peptides with N ‐terminal cyste‐ine/penicillamine....
Tue Apr 28, 2020 12:58
Bioorthogonal chemistry holds great potential to generate difficult‐to‐access protein‐protein conjugate architectures. Current applications are hampered by challenging protein expression systems, slow conjugation chemistry, use of undesirable catalysts, or often do not result in quantitative product formation. Here we present a highly efficient technology for protein functionalization with commonly used bioorthogonal motifs for Diels‐Alder cycloaddition with inverse electron demand (DA inv ). With...
Tue Apr 28, 2020 11:52
Galactosaminogalactan (GAG) is a prominent cell wall component of the opportunistic fungal pathogen Aspergillus fumigatus . GAG is a heteropolysaccharide composed of a ‐1,4‐linked galactose, galactosamine and N ‐acetylgalactosamine residues. To enable biochemical studies, a library of GAG‐fragments was constructed featuring specimens containing a ‐galactose‐, a ‐galactosamine and a ‐ N ‐acetyl galactosamine linkages. Key features of the synthetic strategy include the use of di‐ ...
Tue Apr 28, 2020 11:51
Single‐atom noble metal on catalyst support tend to migrate and agglomerate into nanoparticles due to high surface free energy at elevated temperatures. Temperature‐induced structure reconstruction of support can firmly anchor single‐atom Pt species to adapt high temperature environment. We used Mn 3 O 4 as a restructurable support to load single‐atom Pt and further turned into single‐atom Pt‐on‐Mn 2 O 3 catalyst via high‐temperature treatment, which is extremely stable under calcination conditions...
Tue Apr 28, 2020 11:51
An organic nano‐laser from the micro‐helix structure of an achiral molecule is presented. Highly regular micro‐helixes with left/right‐handed helicity from a distyrylbenzene derivative were fabricated and characterized under microscope spectrometers. These chiral micro‐helixes exhibited unique photonic properties, including helicity‐dependent circularly polarized luminescence, periodic optical waveguiding, and laser behavior. Abstract Organic solid‐state semiconductor lasers are attracting...
Tue Apr 28, 2020 11:46
A double cation–π‐driven strategy is proposed to prepare 2D supramolecular polymers with long‐range ordered molecular hollow hexagons. The double cation–π interaction makes the 2D supramolecular polymers stable. Abstract The cation–π interaction is a strong non‐covalent interaction that can be used to prepare high‐strength, stable supramolecular materials. However, because the molecular plane of a cation‐containing group and that of aromatic structure are usually perpendicular when forming...
Tue Apr 28, 2020 11:37
Benzoselenazole is introduced as a bifunctional selenide reagent for both off‐ and on‐DNA C−H selenylation under rhodium(III) catalysis. The reaction shows great potential in facilitating rapid construction of selenium‐containing DNA‐encoded chemical libraries (SeDELs), and lays the foundation for the development of selenium‐containing drugs. Abstract Conventional direct C−H selenylation suffers from simple selenation with limited atom economy and complicated reaction system. In this work,...
Tue Apr 28, 2020 11:37
Top mimics: Cysteine‐derived chiral carbon dots (CDs) can mimic topoisomerase I and thus mediate the enantioselective topological rearrangement of supercoiled DNA via cleaving one strand of DNA double helix. The gene expression of CD‐treated plasmid DNA is analogous to the regulation effect of topoisomerase I on gene expression. Abstract Nanomaterials with enzyme‐mimetic activities are possible alternatives to natural enzymes. Mimicking enzymatic enantioselectivity remains a great challenge....
Tue Apr 28, 2020 11:35
Photoinduced charge separation in a donor–acceptor–donor‐type perylene bisimide (PBI) is studied by time‐resolved impulsive stimulated Raman spectroscopy. The spectra and calculations suggest not only significant structural changes in the PBI core during symmetry‐breaking charge separation but also similar bond length alternation patterns between the neutral S1 and radical anion states of PBI. Abstract Elucidating structural roles in photoinduced charge transfer is indispensable, as nuclear...
Tue Apr 28, 2020 11:33
Nanocatalosomes are a new type of plasmonic bilayer‐vesicular nanoreactors with few‐nm intershell nanospace, as demonstrated by I. S. Lee et al. in their Research Article (DOI: https://doi.org/10.1002/anie.20200153110.1002/anie.202001531). They possess numerous interlayer‐confined catalytically active cavities harnessing synergistic plasmonic–catalytic effects and performing highly efficient solar light‐induced organic reactions.
Tue Apr 28, 2020 11:29
Catch and release: The vesicular storage and release of catecholamine in adrenal chromaffin cells from wild type and DJ‐1 protein‐deficient mice were quantified by electrochemical methods at the single vesicle/cell level. It was found that DJ‐1 deficiency prolongs the duration of exocytotic events, providing new chemical insights into the pathology of Parkinson's disease. Abstract DJ‐1 protein deficiency caused by PARK7 gene mutation has been suggested to closely relate to Parkinson's disease...
Tue Apr 28, 2020 11:29
The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication, a Cu‐catalyzed borocarbonylative coupling of unactivated alkenes with alkyl halides for the synthesis of β‐boryl ketones has been developed. A broad range of β‐boryl ketone derivatives was prepared in moderate to excellent yields with complete regioselectivity. Abstract The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication,...
Tue Apr 28, 2020 11:29
Gamma‐ray irradiation was introduced for zeolite synthesis. The crystallization process of zeolite NaA, NaY, Silicalite‐1, and ZSM‐5 were accelerated. More mesopores were created during the process; the adsorption capacity of CO2 in NaA thus increased 6‐fold relative to without γ‐ray irradiation. Hydroxyl free radicals generated by γ‐rays accelerated the crystallization of zeolite NaA. Abstract Gamma‐ray (γ‐ray) irradiation was introduced into zeolite synthesis. The crystallization process...
Tue Apr 28, 2020 11:29
Quenched: An external quenching method based on flow microreactors allows the generation and use of short‐lived fluoro‐substituted methyllithium agents, such as fluoromethyllithium, fluoroiodomethyllithium, and fluoroiodostannylmethyllithium. Highly chemoselective reactions have been developed, opening new opportunities in the synthesis of fluorinated molecules using fluorinated organometallics. LDA=lithium diisopropylamide. Abstract The external quenching method based on flow microreactors...
Tue Apr 28, 2020 11:28
Give me azide radicals! Stable and storable polymer‐bound bisazido‐iodate(I) anions are a source of azide radicals upon photochemical activation. These promote azidooxygenations of alkenes and C−H abstraction of alcohols. The latter reactivity initiates the chemoselective oxidation of secondary alcohols and C−H abstraction of aldehydes. Abstract This report discloses the photochemical homolytic cleavage of iodine azide after its formation following release from polymer‐bound bisazido iodate(I)...
Tue Apr 28, 2020 11:22
Best of two worlds: Lateral fusion of azaacenes onto a quinoidal system furnishes stable diradicals with a radical character (y) of up to 0.99. All compounds exhibit paramagnetic behavior as determined by EPR and NMR spectroscopy and SQUID measurements, revealing thermally populated triplet states with an extremely low‐energy gap ΔE ST of 0.58 to 1.0 kcal mol−1. The species are persistent in solution (half‐life≈14–21 h), and they are stable for weeks in the solid state. Abstract Quinoidal...
Tue Apr 28, 2020 11:21
Good support counts: Carbon‐supported nickel nanoparticles with an optimal level of strain are very active for the hydrogen oxidation and evolution reactions. Abstract The hydroxide‐exchange membrane fuel cell (HEMFC) is a promising energy conversion device. However, the development of HEMFC is hampered by the lack of platinum‐group‐metal‐free (PGM‐free) electrocatalysts for the hydrogen oxidation reaction (HOR). Now, a Ni catalyst is reported that exhibits the highest mass activity in HOR...
Tue Apr 28, 2020 11:19
The electronic effect between neighboring Zn/Co monomers, that effectively enhances the *COOH adsorption and thus boosts CO2 electroreduction to CO is described. Abstract It is of great significance to reveal the detailed mechanism of neighboring effects between monomers, as they could not only affect the intermediate bonding but also change the reaction pathway. This paper describes the electronic effect between neighboring Zn/Co monomers effectively promoting CO2 electroreduction to CO. Zn...
Tue Apr 28, 2020 11:19
We demonstrate herein an all‐optical switch based on stimuli‐responsive and photochromic‐free metal‐organic framework (HKUST‐1). Ultrafast near‐infrared laser pulses stimulate a reversible 0.4 eV blue shift of the absorption band with up to 200 s ‐1 rate due to dehydration and concomitant shrinking of the structure‐forming [Cu 2 C 4 O 8 ] cages of HKUST‐1. Such light‐induced switching enables the remote modulation of intensities of photoluminescence of single crystals of HKUST‐1 as well visible...
Mon Apr 27, 2020 22:33
A nitrosyl ligand is a poor donor due to its stable valence‐electron pairs. Nitrosyl–metal bonding thus relies on the two interactions between the pair of N–O‐π* and two of the metal’s d orbitals. These (back)bonds are largely covalent which makes their allocation in the course of an oxidation‐state determination rather ambiguous. However, apart from M–N–O‐angle or net‐charge considerations, IUPAC’s ‘ionic approximation’ is a useful tool to reliably classify nitrosylmetal complexes in an orbital‐centred...
Mon Apr 27, 2020 22:00
Like silicon, single crystals of organic semiconductors are pursued to attain intrinsic charge transport properties. However, they are intolerant to mechanical deformation, impeding their applicability in flexible electronic devices. Such contradictory properties, namely exceptional molecular ordering and mechanical flexibility are unified in this work. We discover that bis(triisopropylsilylethynyl)pentacene (TIPS‐P) crystals can undergo mechanically induced structural transitions to exhibit superelasticity...
Mon Apr 27, 2020 21:06
Synthetic DNA has emerged as a powerful self‐assembled material for the engineering of nanoscale supramolecular devices and materials. Initial examples were focused on thermodynamically driven self‐assembly of DNA‐based structures with exquisite near‐angstrom control of their geometry. More recently dissipative self‐assembly of DNA‐based supramolecular structures has emerged as a novel approach providing access to a new class of kinetically‐controlled DNA materials with unprecedented life‐like properties....
Mon Apr 27, 2020 19:05
Electronic textiles that are thin, lightweight, flexible and breathable have been widely explored with a variety of functionalities including power supplying, displaying and sensing, which may revolutionize many fields such as communication, health care and artificial intelligence. To date, unfortunately, computing is the missing puzzle to close their functional loop. Memristor is compatible with the interwoven structure and fabricating process in textile due to its two‐terminal and crossbar configuration....
Mon Apr 27, 2020 19:04
Hydrogen peroxide (H 2 O 2 ) is widely used in today’s chemical industry as an oxidant and bleaching agent, whilst also finding medical utilization as a mild antiseptic. Over the past few years, researchers have targeted the discovery of low cost electrocatalysts which can selectively reduce dioxygen (O 2 ) to H 2 O 2 , with modest success to date. Herein, we report the successful synthesis of carbon‐supported Ni(II) single atom catalysts possessing a tetradentate Ni‐N 2 O 2 coordination via...
Mon Apr 27, 2020 18:32
In this communication, we report an unprecedented β‐regioselective radical inverse hydroboration (compared with ionic hydroboration) of α, β‐unsaturated amides with NHC‐BH3 enabled by the photoredox catalysis. The density functional theory (DFT) calculations show that the unique photoredox cycle is a key factor to control the β‐regioselective radical hydroboration, which makes the energy barrier is lower than other pathways. This protocol provides a general and convenient route to construct a wide...
Mon Apr 27, 2020 17:34
In search of new anti‐tuberculars compatible with anti‐retroviral therapy we re‐identified amicetin as a lead compound. Amicetin’s binding to the 70S ribosomal subunit of Thermus thermophilus ( Tth ) has been unambiguously determined by crystallography and reveals it to occupy the peptidyl transferase center P‐site of the ribosome. The amicetin binding site overlaps significantly with that of the well‐known protein synthesis inhibitor balsticidin S. Amicetin, however, is the first compound structurally...
Mon Apr 27, 2020 17:05
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