Key points Gastric vagal afferent responses to tension are dampened in high fat diet‐induced obesity. Endocannabinoids are known to dose‐dependently inhibit and excite gastric vagal afferents but their effect on gastric vagal afferents in diet‐induced obesity are unknown. In individual gastric vagal afferent neurons of diet‐induced obese mice the co‐expression of components of the endocannabinoid system, including CB1, GHSR, TRPV1, and FAAH, was increased compared to lean mice. In high...
Wed Apr 01, 2020 22:43
Key points Spinal cord dorsal horn srGAP3 increases in the initiation phase of neuropathic pain and decreases in the maintenance phase. However, Rac1 activity which can be reduced by srGAP3, decreased in the initiation phase and increased in the maintenance phase. The increased srGAP3 in the initiation phase promotes new immature dendritic spines instigating neuropathic pain. Decreased srGAP3 in the maintenance phase enhances Rac1 activity facilitating maturation of dendritic spines and the...
Wed Apr 01, 2020 22:09
Key points Airway projecting sensory neurons arising from the jugular vagal ganglia terminate centrally in the brainstem paratrigeminal nucleus, synapsing upon neurons expressing the neurokinin 1 receptor. This study aimed to assess the involvement of paratrigeminal neurokinin 1 receptor neurons in the regulation of cough, breathing and airway defensive responses. Lesioning neurokinin 1 receptor expressing paratrigeminal neurons significantly reduced cough evoked by inhaled bradykinin but...
Wed Apr 01, 2020 21:53
High‐throughput metabolic analysis is of significance in diagnostics, while tedious sample pretreatment has largely hindered its clinic application. Herein, we designed FeOOH@ZIF‐8 composites with enhanced ionization efficiency and size‐exclusion effect for laser desorption/ionization mass spectrometry (LDI MS) based metabolic diagnosis of gynecological cancers. The FeOOH@ZIF‐8 assisted LDI MS achieved rapid, sensitive, and selective metabolic fingerprints of the native serum without any enrichment...
Wed Apr 01, 2020 20:46
Here we present an“immortal" N ‐(diphenylphosphanyl)‐1,3‐diisopropyl‐4,5‐dimethyl‐1,3‐dihydro‐2H ‐imidazol‐2‐imine/diisobutyl (2,6‐di‐tert‐butyl‐4‐methylphenoxy) aluminum (P(NIiPr)Ph2/(BHT)AliBu2)‐based frustrated Lewis pair (FLP) polymerization strategy for rapid and scalable synthesis of the sequence‐controlled multiblock copolymers at room temperature. Without addition of extra initiator or catalyst and complex synthetic procedure, this method enabled us to achieve a tripentacontablock copolymer...
Wed Apr 01, 2020 19:59
On‐surface assembly of hydrogen‐ and halogen‐bonded supramolecular graphyne‐like networks from functionalized triethynyltriazine derivatives on metal surfaces, Au(111) and Ag(111), are described. The networks are stabilized by N⋅⋅⋅H−C(sp) bonds and N⋅⋅⋅Br−C(sp) bonds to the triazine core. Abstract Demonstrated here is a supramolecular approach to fabricate highly ordered monolayered hydrogen‐ and halogen‐bonded graphyne‐like two‐dimensional (2D) materials from triethynyltriazine derivatives...
Wed Apr 01, 2020 18:30
To achieve unique molecular recognition, rational control of flexibility of porous coordination polymers (PCPs) is highly sought; however, remains exclusive. From a thermodynamic perspective, the competitive relationship between the structural deformation energy ( Edef ) of soft PCPs and the guest interaction is key for selective guest‐triggered structural transformation behavior. Therefore, it is vital to investigate and control the E def to regulate this competition for flexibility control....
Wed Apr 01, 2020 18:28
The 9‐borataphenanthrene anion is easily accessed by deprotonation of a 9,10‐dihydro‐9‐boraphenanthrene and its diverse reactivity is investigated. Alkylation occurs at the carbon adjacent to boron and room temperature hydroboration occurs across the B=C bond. The π ‐manifold of the central BC 5 ring coordinates to chromium in an η 6 fashion while only the B=C bond binds η 2 to gold, indicating versatility of the 9‐borataphenanthrene anion as a ligand. Supporting calculations rationalize...
Wed Apr 01, 2020 18:21
Nanomotors: The first example of a DNA origami nanomotor that processively converts chemical fuel into sustained mechanical motion is presented. Tunable DNA origami motors travel linearly for micron distances at nm/s speeds. Abstract Inspired by biological motor proteins, that efficiently convert chemical fuel to unidirectional motion, there has been considerable interest in developing synthetic analogues. Among the synthetic motors created thus far, DNA motors that undertake discrete steps...
Wed Apr 01, 2020 17:37
A concept for stabilizing highly sensitive and explosive copper(II) azide with 1N‐substituted tetrazoles is described. It was possible to stabilize the system by the use of high‐nitrogen and highly endothermic ligands. The sensitivities of the resulting energetic copper coordination compounds can be tuned further by variation of the alkyl chain of the ligands or by phlegmatization of the complexes with classical additives during the synthesis. It is demonstrated, using the compound based on 1‐methyl‐5H‐tetrazole...
Wed Apr 01, 2020 15:42
Paramount interest and challenges remain in designing and synthesizing catalysts with nature‐like complexities at few‐nm scale to harness unprecedented functionalities by using sustainable solar light. We introduce “nanocatalosomes”— bio‐inspired bilayer‐vesicular design of nanoreactor with metallic bilayer hollow shell‐in‐shell structure, having numerous controllable confined cavities within few‐nm interlayer space, customizable with different noble metals. The intershell‐confined plasmonically‐coupled...
Wed Apr 01, 2020 15:38
An S‐shaped double helicene‐like molecule (>99% ee), possessing stable helical chirality, has been synthesized by the rhodium(I)/difluorphos complex‐catalyzed highly diastereo‐ and enantioselective intramolecular double [2+2+2] cycloaddition of a 2‐naphthol‐ and benzene‐linked hexayne. The collision between two terminal naphthalene rings destabilizes the helical chirality of the Sshaped double helicene‐like molecule, but the introduction of two additional fused benzene rings significantly increases...
Wed Apr 01, 2020 13:08
A native‐chemical‐ligation‐assisted diaminodiacid strategy was developed for the chemical synthesis of peptide disulfide surrogates, forming ring sizes of up to 50 amino acids. The method can facilitate the engineering of biologically interesting disulfide‐containing peptides, and may widen the horizon of peptide‐based research tools and diagnostic or therapeutic reagents. Abstract The use of synthetic bridges as surrogates for disulfide bonds has emerged as a practical strategy to obviate...
Wed Apr 01, 2020 11:35
Strong links: Polymers containing luminophores or sub‐luminophores may display enhanced emission upon crosslinking by covalent, supramolecular, and ionic bonding, and by through‐space interactions in confined domains. In this Minireview the theoretical background is discussed and numerous examples are provided, which may guide researchers in crosslinkage techniques to improve luminescent systems. Abstract The crosslink‐enhanced emission effect was first proposed to explore the strong luminescence...
Wed Apr 01, 2020 12:11
The advantage of defects: The effect of a tropone moiety on the nonlinear optical properties of ribbon‐shaped nanographenes is unequivocally demonstrated. Curved edges created by the inclusion of heptagonal carbocycles enhance the two‐photon absorption on graphene molecules. Abstract A new family of distorted ribbon‐shaped nanographenes was designed, synthesized, and their optical and electrochemical properties were evaluated, pointing out an unprecedented correlation between their structural...
Wed Apr 01, 2020 12:08
Activatable probes: Second near‐infrared fluorescence, chemiluminescence, and photoacoustic imaging, with their respective advantages of minimized light scattering, eliminated external excitation, and ultrasound detection, have attracted increasing attention for deep‐tissue in vivo imaging. This Minireview discusses the molecular design strategies and sensing mechanisms for activatable molecular probes, along with their deep‐tissue optical imaging applications. Abstract Optical imaging plays...
Wed Apr 01, 2020 12:07
G4 imaging: A tripodal cationic fluorescent probe, NBTE, was used for the visualization (based on fluorescent lifetime) and quantification (based on photon counts) of G‐quadruplex DNA in live cells by fluorescence lifetime imaging microscopy (FLIM). Structural studies provided a structural basis for the DNA‐topology‐based fluorescence response of NBTE. Abstract G‐quadruplex DNA show structural polymorphism, leading to challenges in the use of selective recognition probes for the accurate detection...
Wed Apr 01, 2020 12:07
Spinel tap: Nitrate is prepared by direct electrochemical oxidation of nitrogen on ZnFex Co2−x O4 spinel oxides in alkaline electrolyte. The combined effect of Fe and Co in octahedral sites is found advantageous for nitrate formation and spinel ZnFe0.4Co1.6O4 exhibits the highest nitrate yield. Abstract Nitrates are widely used as fertilizer and oxidizing agents. Commercial nitrate production from nitrogen involves high‐temperature‐high‐pressure multi‐step processes. Therefore, an alternative...
Wed Apr 01, 2020 12:06
All systems Ar go: A PdII‐catalyzed enantioselective C(sp3)−H arylation of ketones using an α‐amino acid as a chiral transient directing group is reported. 3‐Nitro‐5‐trifluoromethyl‐2‐pyridone was identified as an effective ligand, and acts as an acetate surrogate to accelerate C−H bond cleavage. Combining an electron‐deficient 2‐pyridone ligand with different silver salts enables control of the rate‐limiting step (RLS), thereby leading to high enantioselectivity. Abstract The use of chiral...
Wed Apr 01, 2020 12:06
Recent Progress in the Development of Solid‐State Luminescent o‐Carboranes with Stimuli Responsivity
Shine on you crazy diamond! In this Minireview a series of arene‐modified o‐carboranes are described that display solid‐state emission as well as stimuli‐responsive optical properties. The unique photochemistry of these o‐carboranes, such as aggregation‐induced emission (AIE), twist‐induced charge‐transfer (TICT) emission, and solid‐state excimer emission, is explored. Abstract o‐Carborane, a cluster compound containing boron and adjacent carbon atoms, displays intriguing luminescent properties....
Wed Apr 01, 2020 12:04
Allosteric inhibition of kinase signaling is a promising approach for the targeted discovery of therapeutics with exceptional selectivity and the ability of overcoming the acquired resistance of the orthosteric ATP‐binding site inhibitors. The recent developments of allosteric kinase inhibitors that bind outside the catalytic kinase domain further warrant considerable interest and offer unique opportunities in this area. Abstract Drugs that function through allosteric inhibition of kinase signaling...
Wed Apr 01, 2020 12:03
Pi at last! Milling K[1,3‐(SiMe3)2C3H3] (=K[A′]) with MgX2 (X=Cl, Br) produces the orange heterometallic allyl complex [K2MgA′4]. The crystal structure contains the first terminal η3‐bound allyl ligand on a Mg center. Methyl methacrylate is polymerized by this complex, with activities that are comparable to K[A′] and greater than that of [{MgA′2}2]. Abstract Milling two equivalents of K[1,3‐(SiMe3)2C3H3] (=K[A′]) with MgX2 (X=Cl, Br) produces the allyl complex [K2MgA′4] (1). Crystals grown...
Wed Apr 01, 2020 12:03
Lead free: The first halide double perovskite ferroelectric was rationally designed by the substitution of the lead component and cation intercalation of n‐propylamine. The material exhibits fascinating ferroelectricity with a notable saturation polarization of about 1.5 μC cm−2, as well as extraordinary semiconducting performance, including high on/off ratios of about 104, fast response rates of 141 μs, and detectivity as high as 5.3×1011 Jones. Abstract Halide double perovskites have recently...
Wed Apr 01, 2020 12:03
A Pascal‐triangle lattice is constructed by using a careful selection of protein building blocks with anisotropic shapes and two sets of carbohydrate binding sites. Moreover, the dynamic and exchangeable nature of non‐covalent interactions make the further manipulation on 2D lattices to 3D crystals possible. Abstract A protein Pascal triangle has been constructed as new type of supramolecular architecture by using the inducing ligand strategy that we previously developed for protein assemblies....
Wed Apr 01, 2020 11:59
The tricyclic natural product pimara‐15‐en‐3α‐8α‐diol comprises three quaternary carbon centers and six stereocenters, four of which are adjacent. Syn‐pentane interactions of all four axial substituents generate considerable strain in the molecule. Reported here is a 13 step synthesis that features a powerful polyene tetracyclization involving an unprecedented transannular endo‐termination step. Abstract Polyene cyclizations are one of the most powerful and fascinating chemical transformations...
Wed Apr 01, 2020 11:58
A liposomal composite nanosystem has been constructed for tumor‐specific chemotherapy, which enables differential stress sensitization in between cancer and normal cells, capable of restricting the toxicity of chemotherapy exclusively within tumor regions. Abstract Most of current nanomedicines are administrated intravenously to favour tumor accumulation through enhanced permeability and retention (EPR) effect, which, however, suffers from several drawbacks such as low drug bioavailability...
Wed Apr 01, 2020 11:56
Conquering chaos: IrOx nanoparticles were shown to possess acid‐activated multienzyme‐like properties, and further loading with glucose oxidase (GOD) created a nanozyme (IrOx –GOD) that mimicked four enzymes. The introduction of IrOx –GOD into chaotic tumors led to a “butterfly effect” of initial starvation therapy and subsequent pressure of multiple reactive oxygen species (ROS) to completely disrupt the self‐adaption of cancer cells (see picture). Abstract Chaos and the natural evolution...
Wed Apr 01, 2020 11:56
Take me down to the sensitized city: Chiral eniminium ions undergo electron transfer and/or energy transfer (sensitization) with commonly used ruthenium or iridium photocatalysts, with only the latter mechanism being productive in an intermolecular [2+2] photocycloaddition. Employing visible‐light irradiation the reaction gave access to enantioenriched cyclobutanecarbaldehydes, after hydrolysis, in up to 74 % yield and 96:4 er (17 examples). Abstract Chiral eniminium salts, prepared from α,β‐unsaturated...
Wed Apr 01, 2020 11:55
The syntheses of new derivatives of indolo[3,2‐b]carbazole have enabled a comprehensive study on the remarkable electronic structure of indolo[3,2‐b]carbazole. This work has also led to the development of a new n‐type organic semiconductor for solution‐processed organic field effect transistors. Abstract Indolo[3,2‐b]carbazole presents a π‐skeleton with a remarkable electronic structure and interesting potential applications. It is, however, also associated with ambiguity and controversy. Herein,...
Wed Apr 01, 2020 11:54
Turning the light off: Self‐sustained NiI/III cycles are established as a potentially general paradigm in photoredox cross‐coupling reactions. It is shown that photoredox‐like reactivity can be recapitulated with high fidelity in the complete absence of light across multiple substrates and transformations, thus obviating the need for high‐energy photons and precious‐metal photocatalysts. Abstract Self‐sustained NiI/III cycles are established as a potentially general paradigm in photoredox Ni‐catalyzed...
Wed Apr 01, 2020 11:54
The PICSA concept (polymerization‐induced chiral self‐assembly) is demonstrated by constructing hierarchical supramolecular chiral azobenzene‐containing block copolymer (Azo‐BCP) assemblies in a controlled manner. The construction, dynamic reversibility, and morphological effect of supramolecular chirality in azo liquid‐crystalline assemblies are presented. Abstract Hierarchical supramolecular chiral liquid‐crystalline (LC) polymer assemblies are challenging to construct in situ in a controlled...
Wed Apr 01, 2020 11:53
The noble art: Noble‐metal dichalcogenides and phosphochalcogenides are a novel class of two‐dimensional materials. This Minireview summarizes the progress in their synthesis, characterization, and application, highlighting their unique structural features and relationships. Abstract Noble‐metal chalcogenides, dichalcogenides, and phosphochalcogenides are an emerging class of two‐dimensional materials. Quantum confinement (number of layers) and defect engineering enables their properties to...
Wed Apr 01, 2020 11:52
Saturated benzene mimetics, 2‐oxabicyclo[2.1.1]hexanes, were synthesized by P. K. Mykhailiuk and co‐workers (DOI: https://doi.org/10.1002/anie.20200054810.1002/anie.202000548). The cover picture shows a constellation of such a molecule, that was designed as a water‐soluble analogue of both bicyclo[1.1.1]pentanes and meta‐disubstituted benzenes. The key reaction in the synthesis is an iodocyclization. The obtained compounds are chemically and metabolically stable, and are ready for the direct use...
Wed Apr 01, 2020 11:52
In neutral: The nitrate reduction reaction (NRR) is essential for water remediation. In an artificial NRR catalyst, an enzyme mimetic intermediate has been identified for the first time in the activation of the NRR at neutral pH. The newly identified intermediate is stable in neutral water, and the secondary electronic interactions were found to play a key role. Abstract Nitrate is a pervasive aquatic contaminant of global environmental concern. In nature, the most effective nitrate reduction...
Wed Apr 01, 2020 11:51
Large‐scale lamellar Mn MOFs are synthesized by a strategy involving a bi‐phase system. The continuous ligand supply along with capping agent are effective in promoting layer‐by‐layer growth and achieving large crystal sizes. The stabilized lamellar morphology enables bromine intercalation for layered MOFs. Abstract A modulated bi‐phase synthesis towards large‐scale manganese 1,4‐benzenedicarboxylate (MnBDC) MOFs with a precise control over their morphology (bulk vs. layered) is presented....
Wed Apr 01, 2020 11:50
Wed Apr 01, 2020 11:50
Sphere factor: A diffusion–reaction competition mechanism reveals the principle of spherical Li deposition. By controlling the rate‐determining step of Li deposition, different Li deposition scenarios are revealed, in which the diffusion‐controlled process tends to give dendritic Li deposition while the reaction‐controlled process leads to spherical Li deposition. Abstract Lithium metal is recognized as one of the most promising anode materials owing to its ultrahigh theoretical specific capacity...
Wed Apr 01, 2020 11:42
A silica‐mediated MOF‐templated (SMMT) approach is used to generate an overhang‐eave carbon cage decorated with single‐atom iron catalysts for oxygen reduction (ORR), as reported by Q. Xu and co‐workers in their Communication (DOI: https://doi.org/10.1002/anie.20200266510.1002/anie.202002665). This structure furnishes more stretched edges as compared to three‐phase boundaries, supporting the mass transport of ORR‐relevant species and providing maximum exposure of the atomically dispersed/catalytically...
Wed Apr 01, 2020 11:42
Two for Two: A highly enantioselective annulation of two C−H bonds with alkynes without built‐in chelating groups was achieved through Ni−Al bimetallic catalysis enabled by a bulky BINOL‐derived secondary phosphine oxide (SPO) ligand. This reaction uses readily available formamides as starting materials and provides concise access to a broad range of chiral ferrocenes in 40–98 % yield and 93–99 % ee. Abstract Twofold C−H annulation of readily available formamides and alkynes without built‐in...
Wed Apr 01, 2020 11:41
Hi, neighbor: A mixed‐valent, trinuclear molecular platform enables precise site‐specific substitution at either of its divalent or trivalent metal position to prepare target heterotrimetallic molecular precursors with desired metal combinations. Abstract A known trinuclear structure was used to design the heterobimetallic mixed‐valent, mixed‐ligand molecule [CoII(hfac)3−Na−CoIII(acac)3] (1). This was used as a template structure to develop heterotrimetallic molecules [CoII(hfac)3−Na−FeIII(acac)3]...
Wed Apr 01, 2020 11:38
On the move: Thiol–anhydride networks were fabricated and assessed for their dynamic reversible characteristics. Three anhydrides (maleic, succinic, and phthalic) were used to create dynamic thermosets of diverse propensities for thioester anhydride link reversion. An impressive degree of control over their dynamic responsiveness was achieved. Abstract The reaction of thiols and anhydrides to form ring opened thioester/acids is shown to be highly reversible and it is accordingly employed in...
Wed Apr 01, 2020 11:38
An anthracene‐based fluorescent linker and a hemicyanine‐containing CN−‐responsive linker were sequentially installed into the lattice of the metal–organic framework PCN‐700. The proximity and periodic arrangement of the anthracene and hemicyanine linkers facilitated efficient energy transfer between the two components, causing fluorescence quenching. The binding of CN− to hemicyanine inhibited this energy transfer, resulting in fluorescence. Abstract The controlled synthesis of multicomponent...
Wed Apr 01, 2020 11:37
Increased attention SPAN: Recent advances in electrolyte regulation towards stable lithium‐metal anodes for Li‐sulfurized polyacrylonitrile (SPAN) batteries are summarized to afford design strategies of solvents, lithium salts, additives, and gel electrolyte. Abstract Lithium–sulfur (Li–S) batteries are highly regarded as the next‐generation energy‐storage devices because of their ultrahigh theoretical energy density of 2600 Wh kg−1. Sulfurized polyacrylonitrile (SPAN) is considered a promising...
Wed Apr 01, 2020 11:37
Nucleotide halogenase: The biosynthetic chlorination that results in the nucleoside adechlorin requires an iron‐α‐ketoglutarate‐dependent halogenase, AdeV. AdeV regioselectively halogenates C2′ of either dAMP, ddAMP, or dIMP. Abstract While halogenated nucleosides are used as common anticancer and antiviral drugs, naturally occurring halogenated nucleosides are rare. Adechlorin (ade) is a 2′‐chloro nucleoside natural product first identified from Actinomadura sp. ATCC 39365. However, the installation...
Wed Apr 01, 2020 11:34
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