Background. The prognosis of pancreatic adenocarcinoma (PAAD) is extremely poor and has not been improved. Thus, an effective method to assess the prognosis of patients must be established to improve their survival rate. Method. This study investigated immune-related genes that could be used as potential therapeutic targets for PAAD. Level 3 gene expression data from the PAAD cohort and the relevant clinical information were obtained from The Cancer Genome Atlas (TCGA) database. For validation, other...
Tue Jun 09, 2020 19:20
Background. A deficiency in steroid 5α-reductase type 2 is an autosomal recessive disorder. Affected individuals manifested ambiguous genitalia, which is caused by decreased dihydrotestosterone (DHT) synthesis in the fetus. Methods. We analyzed 25 patients with 5α-reductase deficiency in China. Seventeen of the 25 patients (68%) were initially raised as females. Sixteen patients changed their social gender from female to male after puberty. Results. Eighteen mutations were identified in these patients....
Tue Jun 09, 2020 18:20
Long-term muscle fatigue is a major cause of injury. Drugs/nutrients from herbal medicines that prevent fatigue remain a major research focus. In China, a prescription composed of Polygonati Rhizoma and Notoginseng Radix et Rhizoma has been commonly used as a herb and food nutrient, providing protection against fatigue in the clinic. To date, the mechanisms through which this prescription prevented fatigue are unknown. Here, we identified the effects of this prescription on muscle fatigue based on...
Tue Jun 09, 2020 18:05
Lung tissue is abundant with immune cells that form a powerful first defense against exotic particles and microbes. The malignant phenotype of lung adenocarcinoma (LUAD) is defined not only by intrinsic tumor cells but also by tumor-infiltrating immune cells (TIICs) recruited to the immune microenvironment. Understanding more about the immune microenvironment of LUAD could function in sorting out patients more likely with high risk and benefit from immunotherapy. Twenty-two types of TIICs were estimated...
Tue Jun 09, 2020 17:05
Abstract Background The airway epithelium plays an important role in wound repair, host defense and is involved in the immunopathogenesis of asthma. Genome wide association studies have described associations between ST2/Interleukin (IL)‐33 genes in asthma, but its role in bronchial epithelium is unclear. Methods ST2 expression was examined in subjects with asthma and healthy controls in bronchial epithelium from biopsies (n=27 versus n=9) and brushings (n=34 versus n=20) by immunohistochemistry...
Tue Jun 09, 2020 21:15
Abstract Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis.It strengthens the ARIA change management strategy in the prevention and managementof airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical...
Mon Jun 08, 2020 14:30
Mon Jun 08, 2020 11:54
Abstract Coronavirus disease 2019 (COVID‐19), a respiratory tract infection caused by a novel human coronavirus, the severe acute respiratory syndrome coronavirus 2, leads to a wide spectrum of clinical manifestations ranging from asymptomatic cases to patients with mild and severe symptoms, with or without pneumonia. Given the huge influence caused by the overwhelming COVID‐19 pandemic affecting over three million people worldwide, a wide spectrum of drugs is considered for the treatment in the...
Mon Jun 08, 2020 11:53
Summary Objective This cross‐sectional, observational study assessed the inter‐relationships between painful TMDs, somatic, and psychological symptoms in Asian youths. Methods Study subjects were recruited from a local Polytechnic. Pain‐related TMDs was established with the TMD pain screener (TPS), while somatic and psychological symptoms was assessed with the Patient Health Questionnaire‐15 (PHQ‐15) and Depression, Anxiety and Stress Scales‐21 (DASS‐21). Demographic information, TPS, PHQ‐15,...
Tue Jun 09, 2020 11:59
Abstract Background Some authors state that above‐normal surface electromyography (SEMG) levels during mandibular rest (MR) is a general sign of temporomandibular disorders (TMD). Objective The aim was to compare SEMG levels in the masseter and anterior temporalis areas during MR between patients with disk displacement (DD) and subjects identified as healthy. The hypothesis was that average SEMG levels would be higher in the patients during MR before and after repeated clenches with maximal...
Tue Jun 09, 2020 11:37
Current interest for lone‐pair…π (lp…π) non‐covalent interactions is gaining momentum in biochemistry and (supramolecular)chemistry. However, the physico‐chemical origin of the exceptionally short (≈2.8 Å) oxygen to nucleobase plane distances observed in prototypical Z‐DNA CpG steps remains unclear. Accurate quantum mechanical calculations including SAPT2+3 interaction energy decompositions demonstrate that lp…π contacts do not result from n→π* orbital overlaps but from weak dispersion and electrostatics...
Tue Jun 09, 2020 22:14
Developing graphene‐like two‐dimensional (2D) materials naturally possessing a bandgap has sparked enormous interest. Thanks to the inherent wide bandgap and high mobility in the 2D plane, covalent organic frameworks containing triazine rings ( t ‐COFs) hold great promise in this regard, whilst synthesis of single‐layer t ‐COFs remains highly challenging. Herein, well‐defined, graphene‐like t ‐COF has been fabricated on Au(111). Instead of one/multiple‐step(s) single‐type reactions commonly...
Tue Jun 09, 2020 22:13
Green mining for palladium : As an alternative to platinum‐group element (PGE) mining, a series of porous organic polymer nanotraps were rationally designed for their ability to recover Pd from aqueous solutions as a potential recycling method. Through intramolecular hydrogen bonding, the adsorbent–Pd complex could be stabilized, allowing for selective capture of Pd under environmentally relevant conditions. Abstract To offset the environmental impact of platinum‐group element (PGE) mining,...
Tue Jun 09, 2020 22:00
Fluorescent, DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are applied in a range of applications within nanoscience and nanotechnology. However, their diverse optical properties, mechanism of formation, and aspects of their composition remain unexplored, making the rational design of nanocluster probes challenging. Here, a synthetic procedure is described for obtaining a high yield of emissive DNA‐AgNCs with a C‐loop hairpin DNA sequence, with subsequent purification by size‐exclusion chromatography...
Tue Jun 09, 2020 21:10
Graphene oxide (GO) is experiencing a growing interest by synthetic organic chemists as a promoter of chemical transformations. The synergistic role of the multiple functionalities featuring the nanostructured carbon materials and their π‐domains enables the interplay of specific activation modes towards organic compounds that can explore unprecedented chemical modifications. A detailed comprehension of the mechanistic dictates that governate the transformations guided by GO, is probably the still...
Tue Jun 09, 2020 20:43
An enantioselective intermolecular carboamination of acrylates provides α‐amino esters in good yields and excellent enantiomeric ratios of >99.5:0.5. The RhIII‐catalyzed reaction operates by the asymmetric alkenyl C−H functionalization of enoxysuccinimides to generate the nitrogen and carbon portion for the transfer to the acceptor olefin. Abstract Enantioselective carboaminations of olefins constitute an attractive strategy for a rapid increase in molecular complexity from readily available...
Tue Jun 09, 2020 16:26
Combining structural design and in situ TEM characterization reveals the advances of nanostructure design of alloy‐type anodes for potassium‐ion batteries, leading to electrode materials with improved performance. In situ TEM revealed that the optimized design of electrode structure effectively accommodates huge volume changes of Sb nanoparticles during potassiation/depotassiation processes. Abstract Nanostructure design and in situ transmission electron microscopy (TEM) are combined to demonstrate...
Tue Jun 09, 2020 16:25
The last years have witnessed many gold‐catalyzed reactions of alkynes. One of the most prominent species in the reaction of two alkyne units is the vinyl‐substituted gold vinylidene intermediate. Here, we were able to show that the reaction of a haloacetylene and an alkyne proceeds via a hitherto overlooked intermediate, namely the cyclopropenylmethyl cation. The existence and relative stability of this concealed intermediate is verified by quantum chemical calculations and 13 C‐labeling experiments....
Tue Jun 09, 2020 16:09
Focussing on one step : The transfer of adsorbed hydroxyl (OHad + e−⇄ OH−) has been isolated and identified as a critical step in the alkaline hydrogen evolution reaction on Ni/Co‐modified MoSe2 model catalysts. Abstract The key descriptor that dominates the kinetics of the alkaline hydrogen evolution reaction (HER) has not yet been unequivocally identified. Herein, we focus on the adsorbed hydroxyl (OHad) transfer process (OHad + e− ⇄ OH−) and reveal its crucial role in promoting the overall...
Tue Jun 09, 2020 15:15
Hetero‐liposomes with a structural composition similar to that of eukaryotic cells were prepared by constructing transmembrane peptide frames that mimicked the cell cytoskeleton structure. The conformation and transmembrane mode of the peptides played dominant roles during the frame‐guided assembly (FGA) process. The FGA liposomes were formed with excellent stability and could be utilized as a drug delivery platform. Abstract The shape of eukaryotic cells is determined by the cytoskeleton...
Tue Jun 09, 2020 15:14
A cluster of motile and mature sperm previously immobilized on the BSA‐HA microflake is transported by a magnetically‐driven microhelix, which delivers the sperm‐loaded microflake close to the area of interest. Due to the presence of local proteases, the microflake is then hydrolyzed allowing the sperm release to finally reach the target location. Abstract An integrated system combining a magnetically‐driven micromotor and a synthetized protein‐based hyaluronic acid (HA) microflake is presented...
Tue Jun 09, 2020 15:13
An unprecedented cascade reaction to β‐stereogenic γ‐lactams involving Pd(II)‐catalyzed enantioselective aliphatic methylene C(sp3)−H alkenylation–aza‐Wacker cyclization through syn ‐aminopalladation is reported. Readily available 3,3′‐substituted BINOLs are used as chiral ligands, providing the corresponding γ‐lactams with broad scope and high enantioselectivities (up to 98 % ee ). Abstract Herein, we describe an unprecedented cascade reaction to β‐stereogenic γ‐lactams involving Pd(II)‐catalyzed...
Tue Jun 09, 2020 15:13
Sensing in close quarters : A nucleic acid‐based electrochemical platform able to measure levels of immunoglobulins of type G and E (IgG and IgE) directly in blood serum and other bodily fluids was developed. The antibody detection exploits effective molarity effects that are induced by the spatial confinement of electrochemically active DNA‐based sensing modules at the nanoscale. Abstract Easy‐to‐use platforms for rapid antibody detection are likely to improve molecular diagnostics and immunotherapy...
Tue Jun 09, 2020 15:12
The formation and regeneration of active Cu(I) species is a fundamental mechanistic step in copper‐catalyzed atom transfer radical cyclizations (ATRC). Typically, the presence of the catalytically active Cu(I) species in the reaction mixture is secured by using high Cu(I) catalyst loadings or the addition of complementary reducing agents. In this study we demonstrate how the piezoelectric properties of barium titanate (BaTiO3) can be harnessed by mechanical ball milling to induce electrical polarization...
Tue Jun 09, 2020 15:11
Methanation of carbon dioxide (CO 2 ) is attractive within the context of a renewable energy refinery. Herein, we report an indirect methanation method that harnesses amino‐alcohols as relay molecules in combination with a catalyst comprising ruthenium nanoparticles (NPs) immobilized on a Lewis acidic and robust metal‐organic framework (MOF). The Ru NPs are well dispersed on the surface of the MOF crystals and have a narrow size distribution. The catalyst efficiently transforms amino‐alcohols to...
Tue Jun 09, 2020 14:46
Fluorescence imaging in the second near‐infrared (NIR‐II) window facilitated by aggregation‐induced emission luminogens (AIEgens) is an emerging research field. NIR‐II AIEgens overcome the bottlenecks of penetration depth and fluorescence efficiency, offering high‐performance imaging with enhanced precision. Some reported NIR‐II AIEgens demonstrate capabilities of fluorescence and photoacoustic bimodal imaging, and fluorescence imaging guided photothermal therapy, which not only improves diagnosis...
Tue Jun 09, 2020 14:46
It's electric : An advanced dual‐additive electrolyte containing a unique solvation structure comprising tris(pentafluorophenyl)‐based additives and LiNO3 in a carbonate‐based electrolyte is reported. It can generate a robust outer Li2O solid electrolyte interface (SEI) and a F‐ and B‐containing conformal cathode electrolyte interphase (CEI), thus realizing a stable cell operation when E/C and the N/P ratio decrease to 3.4 g Ah−1 and 2.28, respectively. Abstract A rechargeable Li metal anode...
Tue Jun 09, 2020 12:16
DNA technology was used to precisely regulate both lateral and vertical positioning of T cell activation ligands on the membrane of red blood cells to better mimic natural antigen presenting cells, thereby providing a tool for T cell activation studies and enhanced adoptive immunotherapy. Abstract Artificial antigen presenting cells (aAPCs) with surface‐anchored T cell activating ligands hold great potential in adoptive immunotherapy. However, it remains challenging to precisely control the...
Tue Jun 09, 2020 12:15
Light triggers : Photoinduced electrochemiluminescence (PECL) can be induced at BiVO4 photoanodes in an aqueous electrolyte containing a luminol derivative (L‐012), at a record potential of −0.4 V. Here, the incident light simultaneously triggers L‐012 fluorescence and PECL. The latter process considerably amplifies the luminescence and the potential control allows fine tuning of the overall luminescence. Abstract Photoinduced electrochemiluminescence (PECL) combines semiconductor (SC) photoelectrochemistry...
Tue Jun 09, 2020 12:15
A Li metal anode working at 90 °C is demonstrated in a thermotolerant liquid electrolyte. The anode undergoes 100 cycles in a Li|LiFePO4 battery at 90 °C (10 cycles in a practical carbonate electrolyte). High operation temperature promotes independent and incomplete decomposition of Li salts and solvents to form a distinctive solid electrolyte interphase. Abstract Stable operation at elevated temperature is necessary for lithium metal anode. However, Li metal anode generally has poor performance...
Tue Jun 09, 2020 12:13
A forgotten curiosity : Ixene, a compound that was previously named but never prepared, and its BN‐doped derivative (B2N2‐ixene) were synthesized in two steps from simple intermediates. The effect of BN‐doping, or substitution of carbon–carbon bonds with isoelectronic boron–nitrogen bonds, was elucidated both experimentally and theoretically. Abstract Polycyclic aromatic hydrocarbons (PAHs) are key components of organic electronics. The electronic properties of these carbon‐rich materials can...
Tue Jun 09, 2020 12:13
Triplet materials are designed by introducing heavy atoms to enhance spin–orbit coupling or constructing donor and acceptor units with a twisted conformation to reduce ΔE ST. However, the twisted materials have not been applied in solar cells due to weak absorption and low charge‐transport mobilities. Now two nonplanar acceptors with large π‐conjugated core were constructed that achieved over 15 % efficiency. Abstract Triplet acceptors have been developed to construct high‐performance organic...
Tue Jun 09, 2020 12:13
The lipid phase of the uppermost human skin layer is thought to comprise highly rigid lipids in an orthorhombic phase state to protect the body against the environment. By synthesizing sphingosine‐ d 28 deuterated N‐ lignoceroyl‐D‐ erythro‐ sphingosine (ceramide [NS]), we compare the structure and dynamics of both chains of that lipid in biologically relevant mixtures using X‐ray diffraction, 2 H NMR and infrared spectroscopy. Our results reveal a substantial fraction of sphingosine chains...
Tue Jun 09, 2020 11:40
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, and is uniquely enabled by the 1,4‐azaborine‐based Senphos ligand structure. Tetra‐substituted alkenyl nitriles are obtained providing useful boron‐dienenitrile building blocks that can be further functionalized. The utility of our method has been demonstrated with the synthesis of Satigrel, an...
Mon Jun 08, 2020 22:43
Single‐walled carbon nanotubes (SWCNT) are a 1D nanomaterial that shows fluorescence in the near‐infrared (NIR, > 800 nm). In the past, covalent chemistry was less explored to functionalize SWCNTs as it impairs NIR emission. However, certain sp 3 defects (quantum defects) in the carbon lattice have emerged that preserve NIR fluorescence and even introduce a new, red‐shifted emission peak. Here, we report on quantum defects, introduced using light‐driven diazonium chemistry, that serve as anchor...
Mon Jun 08, 2020 22:11
The contribution of computer assistance and automation to various aspects of discovery in the chemical sciences is discussed in this two‐part Review. This first part describes how discoveries of physical matter, processes, and models are unified as search problems; what to consider when assessing the extent of autonomy in a discovery; and many examples of discoveries in synthetic chemistry, drug discovery, inorganic chemistry, and materials science. Abstract This two‐part Review examines how...
Mon Jun 08, 2020 22:00
I got the Nile blues : Mesoporous silica nanoparticles loaded with Nile blue and capped with a galacto‐hexasaccharide are used for in vivo imaging of cellular senescence. Fluorescence dye emission is quenched inside nanoparticles, yet a remarkable fluorescence is observed upon cap hydrolysis by β‐galactosidase. The probe detects cellular senescence in vitro and in vivo in palbociclib‐treated BALB/cByJ mice bearing breast tumors. Abstract In vivo detection of cellular senescence is accomplished...
Mon Jun 08, 2020 21:02
The long and the short of it : An efficient approach has been established to separate homogeneous, triazole‐linked ubiquitin (Ub) chains. Affinity‐based proteomic profiling allowed the identification of length‐selective interaction partners of K27‐, K29‐, and K33‐linked chains, thereby showing the implications of chain length on Ub chain recognition. Abstract The attachment of ubiquitin (Ub) chains of various length to proteins is a prevalent posttranslational modification in eukaryotes. The...
Mon Jun 08, 2020 21:01
The aromatic diamine 1,10‐phenanthroline acts as a framework‐bound template for the large‐pore aluminophosphate zeotype STA‐28 and can be used to introduce Fe for Al at a single crystallographic site, as verified by Rietveld refinement and annular dark field scanning transmission electron microscopy. Removal of the template leaves a crystalline microporous solid with accessible iron cations. Abstract An AlPO4 zeotype has been prepared using the aromatic diamine 1,10‐phenanthroline and some...
Mon Jun 08, 2020 20:43
Metalation site prediction : The use of simple pK a calculations allowed a reliable prediction of metalation sites in various heterocycles, arenes, olefins, and alkanes, employing the mild base TMPZnCl⋅LiCl. Using this predictive model, also unexplored N ‐heterocycles were investigated, and the obtained deprotonation sites rationalized readily. Abstract The development of a predictive model towards site‐selective deprotometalation reactions using TMPZnCl⋅LiCl is reported (TMP=2,2,6,6‐tetramethylpiperidinyl)....
Mon Jun 08, 2020 20:38
The role of spatial arrangement : Owing to ligand rigidity and spatial demand, the stabilization of a rare S = spin ground state for tetracoordinate CoIV becomes possible, yielding a complex with high thermal stability and potential for applications relying on atomic layer deposition. Abstract Attempted preparation of a chelated CoII β‐silylamide resulted in the unprecedented disproportionation to Co0 and a spirocyclic cobalt(IV) bis(β‐silyldiamide): [Co[(NtBu)2SiMe2]2] (1 ). Compound 1 ...
Mon Jun 08, 2020 20:37
Transition metal catalyzed C‐H activation have shown potential in the functionalization of peptides with expanded structural diversity. Herein, we report the development of late‐stage peptide macrocyclization methods via palladium‐catalyzed site‐selective C(sp 2 )‐H olefination of tryptophan residues at C‐2 and C‐4 positions. This strategy utilizes peptide backbone as endogenous directing groups and provide access to peptide macrocycles with unique Trp‐alkene crosslinks.
Mon Jun 08, 2020 20:27
Dodecavanadate, [V 12 O 32 ] 4− ( V12 ), possesses a 4.4 Å cavity entrance, and the cavity shows unique electrophilicity. Due to the high polarizability, Br 2 was inserted into V12 , inducing the inversion of one of the VO 5 square pyramids to form [V 12 O 32 (Br 2 )] 4− ( V12(Br2) ). The inserted Br 2 molecule was polarized and showed a peak at 185 cm −1 in the IR spectrum. The reaction of V12(Br2) and toluene yielded bromination of toluene at the ring, showing the...
Mon Jun 08, 2020 20:27
Fine mechanics : A systematic experimental and computational study explains why tiny structural changes in the extremities of a molecular axle can allow or prevent its insertion in the cavity of a macrocycle. These results provide guidelines to design interlocked molecules with predetermined dynamic features, that can be used to make nanostructured machines, motors and materials. Abstract The general principles guiding the design of molecular machines based on interlocked structures are well...
Mon Jun 08, 2020 20:23
Azobenzene under lockdown : Photoisomerizable molecules such as azobenzene convert light directly into chemical energy, however, with a low energy efficiency. By systematically reducing the conformational flexibility of azobenzene and thus preventing unproductive photochemical pathways, the energy conversion efficiency was increased from 1.4 % to 18.1 %, which is the largest of any known photochromic compound. Abstract Photochromic systems have been used to achieve a number of engineering functions...
Mon Jun 08, 2020 20:18
Double transfer : New hypervalent iodine(III) reagents are formed by reactions of difluoroiodotoluene with NH‐sulfoximines. When applied in situ, they photocatalytically react with styrenes by transferring a fluoro and a sulfoximidoyl group onto the olefin with high regioselectivity. The operationally simple process provides a variety of fluorine‐containing N‐functionalized sulfoximines, which are difficult to prepare otherwise. Mechanistic investigations reveal the importance of radical intermediates....
Mon Jun 08, 2020 20:13
A Novel d‐Peptide Identified by Mirror‐Image Phage Display Blocks TIGIT/PVR for Cancer Immunotherapy
The d ‐peptide DTBP‐3 was identified, which could effectively block TIGIT/PVR interaction. DTBP‐3 could inhibit tumor growth and metastasis in anti‐PD‐1 resistant tumor model and could serve as a potential candidate for cancer immunotherapy. Abstract The low response rate and adaptive resistance of PD‐1/PD‐L1 blockade demands the studies on novel therapeutic targets for cancer immunotherapy. We discovered that a novel immune checkpoint TIGIT expressed higher than PD‐1 in many tumors especially...
Mon Jun 08, 2020 20:07
Zeolites are one of the most important heterogeneous catalysts, with a high number of large‐scale industrial applications. While the synthesis of new zeolites remain rather limited, introduction of germanium has substantially increased our ability to not only direct the synthesis of zeolites but also to convert them into new materials post‐synthetically. The smaller Ge‐O‐Ge angles (vs. Si‐O‐Si) and lability of Ge‐O bonds in aqueous solutions account for this behaviour. This minireview discusses critical...
Mon Jun 08, 2020 17:45
Targeting epidermal growth factor receptor (EGFR) through an allosteric mechanism provides a potential therapeutic strategy to overcome drug‐resistant EGFR mutations that emerge within the ATP binding site. Here, we develop an allosteric EGFR degrader, DDC‐01‐163, which can selectively inhibit the proliferation of L858R/T790 (L/T) mutant Ba/F3 cells while leaving wildtype EGFR Ba/F3 cells unaffected. DDC‐01‐163 is also effective against osimertinib‐resistant cells with L/T/C797S and L/T/L718Q EGFR...
Mon Jun 08, 2020 17:40
Conjugated aromatic macrocycles are attractive due to their unique photophysical and optoelectronic properties. In particular, the cyclic radially‐oriented π‐system of cycloparaphenylenes (CPPs) gives rise to photophysical properties unlike any other small molecule or carbon nanomaterial. CPPs have tunable emission, possess large extinction coefficients, wide effective Stokes shifts, and high quantum yields. However, accessing bright CPPs with emissions beyond 500 nm remains difficult. Herein, we...
Mon Jun 08, 2020 16:44
Acylboron compounds are emerging as versatile functional groups with applications in multiple research fields. Their synthesis, however, is still challenging and requires innovative methods. This Minireview provides an overview on the obstacles of acylboron synthesis and highlights notable advances within the last three years on new strategies to overcome the challenges posed by the formation of acyl – boron bonds.
Mon Jun 08, 2020 16:39
Emerged as a cost‐effective and robust enzyme mimic, nanozymes have drawn increasing attention with broad applications ranging from cancer therapy to biosensing. Developing nanozymes with both accelerated and inhibited biocatalytic properties in a biological context is intriguing to peruse more advanced functions of natural enzymes, but remains challenging, because most nanozymes are lack of enzyme‐like molecular structures. By re‐visiting and engineering the well‐known Fe‐N‐C electrocatalyst that...
Mon Jun 08, 2020 16:38
In situ tailoring the metal–organic framework (MOF)‐shrouded biohybrids into controllable nanoarchitectures is made possible by a novel peptide‐directed strategy. The biomacromolecules encased in the 2D mesoporous MOF biohybrids show significantly improved bioactivity compared with the hitherto explored 3D microporous MOF biohybrids. Abstract Rationally tailoring a robust artificial coating can enhance the life‐time of fragile biomacromolecules. However, the coating also can restrain the activity...
Mon Jun 08, 2020 16:30
Flexible microcrystals of dithieno[3,2‐a:2′,3′‐c]phenazine exhibit excellent optical‐waveguiding and wavelength‐division‐multiplexing properties in both straight and bent geometries after mechanical micromanipulation with an AFM cantilever tip. A 2×2‐directional coupler made from two bent crystals via micromanipulation split the optical signal into two different splitting ratios depending on the optical path length. Abstract We present the one‐dimensional optical‐waveguiding crystal dithieno[3,2‐a:2′,3′‐c]phenazine...
Mon Jun 08, 2020 16:29
Pyrolysis–etching of a pyridine‐coordinated polymer was used to prepare a porous carbon material with defect edge‐enriched N‐6/N‐5 doping, high surface area, and rich distribution of N defects within the material. This carbonaceous material allows full utilization of surface‐dominated capacitive K storage with ultrastable cycling. Abstract The development of ultrastable carbon materials for potassium storage poses key limitations caused by the huge volume variation and sluggish kinetics. Nitrogen‐enriched...
Mon Jun 08, 2020 16:29
Slipping into place : An anion‐radical pimer consisting of neutral N ‐(n ‐propyl) benzene triimide and its anionic‐radical counterpart has been developed that shows rare magnetic multistability. The magnetic multistability was attributed to slippage of the π‐stacked units and conformational isomerization of the propyl side chains during temperature variation (see picture). Abstract Radical pimers are the simplest and most important models for studying charge‐transfer processes and provide deep...
Mon Jun 08, 2020 16:29
The jet set : The role of dispersion forces in gas‐phase intermolecular association has been studied in the cyclohexanol homodimer using a combination of rotational data and computational methods. The competition between a hydrogen bond (HB) and weak dispersion forces produces multiple isomerism in the cyclohexanol dimer, with six different species being observed in a jet expansion. Abstract The cyclohexanol homodimer acts as a delicate test model of the role of dispersion forces in intermolecular...
Mon Jun 08, 2020 16:29
The Mechanism of the Magnetodielectric Response in a Molecule‐Based Trinuclear Iron Cluster Material
Magnetodielectric response mechanisms are critical for the rational design and synthesis of molecule‐based magnetodielectric materials. Herein, the magnetodielectric response was investigated in the molecule‐based material [Fe 3 O(CH 3 COO) 6 (py) 3 ](py) ( 1 ). Its magnetodielectric coefficient (MD) is ‐2.8% for phase transition III and ‐4.1% for phase transition I. Study of the mechanism of the magnetodielectric response in 1 reveals that its magnetodielectric response at phase transition...
Mon Jun 08, 2020 16:29
The rapid development of organic electronics is closely related to the availability of molecular materials with specific elec‐tronic properties. Here, we introduce a novel synthetic route enabling a unilateral functionalization of acenes along their long side, which is demonstrated by the synthesis of 1,2,10,11,12,14‐hexafluoropentacene ( 1 ) and the related 1,2,9,10,11‐pentafluorotetracene ( 2 ). Quantum chemical DFT calculations in combination with optical and X‐ray absorption spectroscopy...
Mon Jun 08, 2020 16:27
We demonstrate that heterogeneous/biphasic chemical reactions can be monitored with high spectroscopic resolution using zero‐field nuclear magnetic resonance. This is possible because magnetic susceptibility broadening is negligible at ultralow magnetic fields. We show the two‐step hydrogenation of dimethyl acetylenedicarboxylate with para‐enriched hydrogen gas in conventional glass NMR tubes, as well as in a titanium tube. The low frequency zero‐field NMR signals ensure that there is no significant...
Mon Jun 08, 2020 16:26
Abstract: Two dimensional (2D) nanoribbons constitute an emerging nanoarchitecture for advanced microelectronics and energy conversion due to the stronger size confinement effects compared to traditional nanosheets. Triclinic crystalline red phosphorus (cRP) composed by a layered structure is a promising 2D phosphorus allotrope and the tube‐like substructure is beneficial to the construction of nanoribbons. In this work, few‐layer cRP nanoribbons are synthesized and the effectiveness in the electrochemical...
Mon Jun 08, 2020 16:25
Herein we report the first example of ferrocene analogues with two transition‐metal metallole ligands of the general formula (η5‐C4R4M)2Fe in a sandwich structure. Specifically, dinickelaferrocene 2, a type of dimetallametallocene, is efficiently synthesized from the reaction of dilithionickelole 1 with FeBr2 or FeCl2 presumably via a redox process, and is subjected to detailed experimental (single‐crystal X‐ray structural analysis, ICP‐OES, magnetometry, 57Fe Mössbauer, XPS) and theoretical (MOs,...
Mon Jun 08, 2020 16:19
Triene 6π electrocyclization, wherein a conjugated triene undergoes a concerted stereospecific cycloisomerization to a cyclohexadiene, is a reaction of great historical and practical significance. In order to circumvent limitations imposed by the normally harsh reaction conditions, chemists have long‐sought to develop catalytic variants based upon the activating power of metal – alkene coordination. Herein we demonstrate the first successful implementation of such a strategy by utilizing [(C 5 ...
Mon Jun 08, 2020 16:19
Aqueous organic redox flow batteries (AORFBs) have recently received considerable attention for large‐scale energy storage. Among them, quinone derivatives such as 9,10‐anthraquinone‐2,7‐disulfonate (2,7‐AQDS), have been explored intensively due to its potentially low cost and swift reaction kinetics. However, the low solubility in pH‐neutral electrolytes restricts their application to corrosive acidic or caustic systems. Herein, we report the single molecule redox‐targeting reactions of 2,7‐AQDS...
Mon Jun 08, 2020 16:02
POP quiz : A molecular expansion strategy was developed to construct porous organic polymers (POPs) with high surface areas, well‐defined nanopores, and excellent stability for methane storage. These hyper‐crosslinked conjugated polymers (HCCPs) are among the few POPs with Brunauer‐Emmett‐Teller (BET) surface areas exceeding 3000 m2 g−1, and are stable in air, and strongly acid and alkaline environments. Abstract Construction of porous organic polymers (POPs) with high surface areas, well‐defined...
Mon Jun 08, 2020 14:09
The selenium vacancy in crystalline ReSe2 enhances its electroactivity for both nitrogen reduction and hydrogen evolution. To restrict HER, selenium vacancy‐rich ReSe2@carbonized bacterial cellulose (Vr‐ReSe2@CBC) nanofibers are buried between two CBC layers, leading to boosted Faradaic efficiency and ammonia yield on an abrupt interface. Abstract Vacancy engineering has been proved repeatedly as an adoptable strategy to boost electrocatalysis, while its poor selectivity restricts the usage...
Mon Jun 08, 2020 14:09
Ordered mesoMOF microcrystals with a uniform mesopore size of up to 10 nm and thick microporous crystallized walls were constructed through a salt‐mediated template strategy. The structure‐directing effect of triblock copolymers and the Hofmeister effect of salting‐in ions promoted stable nucleation and in situ growth of crystallized MOF walls around surfactant micelles in the aqueous phase. Abstract Ordered mesoporous metal–organic frameworks (mesoMOFs) were constructed with a uniform pore...
Mon Jun 08, 2020 14:08
Aromatic diimides : A facile one‐pot domino synthetic protocol for aromatic diimides via palladium‐catalyzed carbonylation has been established. This methodology not only allows the LUMO levels to be lowered significantly but also provides ordered and closer packing structures, opening up possibilities to the development of n‐type semiconducting materials based on a variety of aromatic systems. Abstract Aromatic diimides are one of the most important chromophores in the construction of n‐type...
Mon Jun 08, 2020 14:08
Solid‐state ATRP : An atom transfer radical polymerization (ATRP) was performed in the solid‐state. The reaction is promoted by ball milling, found to proceed in a controlled fashion and facilitates access to copolymers that are challenging to prepare via solution‐state methods. Abstract Poly(2‐vinylnaphthalene) was synthesized in the solid‐state by ball milling a mixture of the corresponding monomer, a Cu‐based catalyst, and an activated haloalkane as the polymerization initiator. Various...
Mon Jun 08, 2020 14:07
Electrochemically enabled nickel‐catalyzed C−H alkylations with primary and secondary alkyl halides have been accomplished under exceedingly mild reaction conditions with Et3N at room temperature. Detailed mechanistic studies provided support for a nickel(II/III/I) manifold. Abstract Direct alkylations of carboxylic acid derivatives are challenging and particularly nickel catalysis commonly requires high reaction temperatures and strong bases, translating into limited substrate scope. Herein,...
Mon Jun 08, 2020 14:05
Blood contains various biological nanoparticles, including lipoproteins and extracellular vesicles. We highlight that these lipid–protein based nanoparticles can challenge protein corona studies on nanomedicines—with particular focus on liposomes—when using isolation methods that separate according to size and density. Key: high‐, low‐, and very low‐density lipoproteins (HDL, LDL, and VLDL), chylomicron (CM), extracellular vesicle (EV). Abstract The protein corona of nanoparticles has in recent...
Mon Jun 08, 2020 14:04
The combination of diazo compounds and hypervalent iodine(III) reagents has recently enabled the development of valuable synthetic approaches. In this Minireview, this reagent combination is systematically illustrated, with the aim of elaborating the synthetic utility and potential of this concept as a powerful strategy in organic synthesis. Abstract Site‐selective “cut and sew” transformations employing diazo compounds and hypervalent iodine(III) compounds involve the departure of leaving...
Mon Jun 08, 2020 14:04
Bond formation through excitation : Linear, two‐coordinate gold(I) complexes are known to aggregate side‐on through aurophilic interactions. The resulting weak Au–Au contacts are strengthened upon UV irradiation as evidenced by a shortening of the intermetallic distance and the vibrational and electronic absorption and emission characteristics of the resulting excimers. The changes in the redox potentials make [AuI−AuI]* excimers useful intermediates in photoredox catalysis. Abstract Excimers...
Mon Jun 08, 2020 14:04
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