A new protocol for the synthesis of α ‐branched amines by reductive functionalization of tertiary carboxamides and lactams is described. The process relies on the efficient and controlled reduction of tertiary amides by sodium hydride‐sodium iodide composite, in situ treatment of the resulting anionic hemiaminal with trimethylsilyl chloride and subsequent coupling with nucleophilic reagents including Grignard reagents and tetrabutylammonium cyanide. The new protocol exhibits broad functional group...
Fri Apr 24, 2020 15:25
Bad vibrations? 161Dy nuclear resonance vibrational spectroscopy gives direct experimental access to the partial phonon density of states which includes all vibrational modes involving a displacement of the DyIII ion. In combination with density functional theory, an assignment to all intramolecular vibrational modes is possible, paving an ideal path to help to clarify the role of phonons in single‐molecule magnets. Abstract Synchrotron‐based nuclear resonance vibrational spectroscopy (NRVS)...
Fri Apr 24, 2020 14:14
Innocence is bliss: A novel perfluorinated phenazine ammoniumyl radical cation is shown to be a very strong deelectronator (oxidant). It has broad solvent compatibility, can be used together with good sigma donor ligands, and allows access to tetravalent dicationic iron complexes in common laboratory solvents. Abstract The perfluorinated dihydrophenazine derivative (perfluoro‐5,10‐bis(perfluorophenyl)‐5,10‐dihydrophenazine) (“phenazineF”) can be easily transformed to a stable and weighable...
Fri Apr 24, 2020 14:01
Back in the ring! An efficient strategy based on metalloradical catalysis leads to 8‐membered ring compounds. Both dibenzocyclooctenes and monobenzocyclooctadienes can be obtained in high yields under mild reaction conditions. DFT calculations indicate different ring‐closure pathways for the formation of these two structures. Abstract The metalloradical activation of o‐aryl aldehydes with tosylhydrazide and a cobalt(II) porphyrin catalyst produces cobalt(III)‐carbene radical intermediates,...
Fri Apr 24, 2020 14:01
Transition‐Metal‐Free Oxidative Cross‐Coupling of Tetraarylborates to Biaryls Using Organic Oxidants
From B‐aryl to biaryl: Various biaryl and heterobiaryl systems are accessible via selective (cross)‐coupling of readily prepared tetraarylborates through oxidation with Bobbitt's salt. The oxoammonium salt can either be used as a stoichiometric oxidant or as a catalyst in combination with in situ generated NO2 as a cocatalyst and O2 as the terminal oxidant. For reactive borate salts, coupling can also be achieved without the Bobbitt salt by using NO2 as the sole catalyst. Abstract Readily prepared...
Fri Apr 24, 2020 14:01
The chemical use of CO2 as inexpensive, non‐toxic C1 synthon is of utmost topical interest towards a carbon capture and utilization (CCU) strategy. We present the merger of cobalt catalysis and electrochemical synthesis for mild catalytic carboxylations of allylic chlorides with CO2. Styrylacetic acid derivatives were obtained with moderate to good yields and good functional group tolerance. The thus‐obtained products are useful as versatile synthons to γ‐arylbutyrolactones. Cyclic voltammetry and...
Fri Apr 24, 2020 13:54
Solubilization locations play a critical role in developing advanced surfactants and improving solubilization power in micelle‐based applications. However, the current polarity‐based techniques for measuring solubilization locations could come to conflicting conclusions. The key challenge is the unpredictable polarities in the micellar microenvironment. Herein, we introduced an approach, independent of micellar polarities, to measure solubilization locations by covalently linking tetraphenylethylene...
Fri Apr 24, 2020 13:26
Ch‐ch‐changes: Cellular proteins exhibit complex lysine acylation patterns, which are reversed by a small set of substrate‐promiscuous lysine deacetylases (KDACs). A strategy was developed to create KDAC variants with increased selectivity towards acetyl (Ac) over butyryl (Bu) and crotonyl (Cr) modifications through directed evolution by using a novel selection system. These engineered KDACs can be used to dissect the roles of different lysine acylations in cells. Abstract Lysine acylations,...
Fri Apr 24, 2020 13:12
Slip slidin’ away: Aminoborane crystals can be deformed mechanically while retaining high crystallinity because multiple slip planes exist in their high‐symmetry structures. The presence of dihydrogen bonds in a similar semiglobular system, BH3NHMe2, negates ductility. Mechanically castable plastic crystals are appealing for applications such as ferroelectrics and soft robotics. Abstract Ductility is a common phenomenon in many metals but is difficult to achieve in molecular crystals. Organic...
Fri Apr 24, 2020 13:08
The synthetic utility of electrochemical transformations in asymmetric synthesis is described in this Minireview. Three major types of catalytic enantioselective strategies in electrosynthesis, including electrochemical activation of chiral catalyst‐bound substrates, asymmetric cascade electrochemical processes, and chemically modified chiral electrodes, are discussed. Abstract The field of electrochemical synthesis has developed rapidly over the last decade and has provided alternative synthetic...
Fri Apr 24, 2020 13:08
Selective activation: Ru(II) complexes that act as transfer hydrogenation catalysts capable of harnessing endogenous formate in S. aureus to trigger activation of sulfanilamide prodrug as a new antibacterial therapeutic strategy were uncovered. Abstract The abundance and evolving pathogenic behavior of bacterial microorganisms give rise to antibiotic tolerance and resistance which pose a danger to global public health. New therapeutic strategies are needed to keep pace with this growing threat....
Fri Apr 24, 2020 13:08
Light‐controlled thiol‐reactivity: Stable cyclometalated gold(III)‐hydride complexes can photo‐dissociate hydride ligand and form coordinative [Au‐S] adducts, leading to potent suppression of thioredoxin reductase, up to >400‐fold increase of cytotoxicity (vs. dark) towards different cancer cells with little influence by serum albumin, and strong inhibition of angiogenesis in zebrafish models by one‐ or two‐photon excitation. Abstract The specific gold‐sulfur binding interaction renders...
Fri Apr 24, 2020 13:06
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, nickel‐catalyzed C–H alkylations of unactivated 8‐aminoquinoline amides has been realized under exceedingly mild conditions, namely at room temperature, with a mild base and a user‐friendly electrochemical setup. This electrocatalyzed C–H alkylation displays high functional group tolerance...
Thu Apr 23, 2020 22:50
In order to promote the development of photodynamic therapy (PDT), the undesired side effects including low tumor specificity and “always‐on” phenomenon should be avoided. An effective solution is to construct an adaptive photosensitizer that can be activated to generate reactive oxygen species (ROS) in the tumor microenvironment. Herein, we design and synthesize a supramolecular switch based on a host–guest complex containing a water‐soluble pillar[5]arene ( WP5 ) and an AIEgen photosensitizer...
Thu Apr 23, 2020 22:24
ABSolute selectivity: Stemming from supramolecular chemical receptors that rely on lock‐and‐key binding, activity‐based sensing (ABS) methods utilizing a variety of chemical reaction approaches offer the highly selective detection of small molecules and metals in biological systems. This Review discusses key design principles, reaction development, and sensing methods, and gives an outlook on this emerging field. Abstract Emerging from the origins of supramolecular chemistry and the development...
Thu Apr 23, 2020 22:00
The near‐infrared window of fluorescent heptamethine cyanine dyes greatly facilitates biological imaging because there is deep penetration of the light and negligible background fluorescence. But dye instability, aggregation, and poor pharmacokinetics are current drawbacks that limit performance and the scope of possible applications. All these limitations are simultaneously overcome with a new molecular design strategy that produces a charge balanced and sterically shielded fluorochrome. The key...
Thu Apr 23, 2020 21:19
C2‐C3 alkyne/alkene separation is of great importance to industry, however, designing materials for an efficient molecular sieving of alkenes from alkynes with substantial alkyne capacity remains challenging. Here, it is first reported that two novel hydrolytically‐stable layered metal‐organic frameworks, [Cu(dps)2(GeF6)] (GeFSIX‐dps‐Cu, dps=4,4'‐dipyridylsulfide) and [Zn(dps)2(GeF6)] (GeFSIX‐dps‐Zn), can achieve almost complete exclusion of both C3H6 and C2H4 from their alkyne analogues. Furthermore,...
Thu Apr 23, 2020 20:56
The understanding of biomolecular function is coupled to knowledge about the structure and dynamics of these biomolecules, preferably acquired under native conditions. In this regard, pulsed dipolar EPR spectroscopy (PDS) in conjunction with site‐directed spin labeling (SDSL) is an important method in the toolbox of biophysical chemistry. However, the currently available spin labels have diverse deficiencies for in cell applications, e.g. low radical stability or long bioconjugation linkers. In this...
Thu Apr 23, 2020 20:35
Single‐atom catalysts (SACs) show great promises for electrochemical CO 2 reduction reaction (CRR), but the low density of active sites and the poor electrical conduction and mass transport of the single‐atom electrode greatly limit their apparent performances. Arraying SACs provides an encouraging strategy for designing structured and functional single‐atom electrode with high density of exposed active sites and promoted electrical conductivity and mass transport. Herein, we prepared a nickel...
Thu Apr 23, 2020 20:30
A highly bent neutral triarylborane, 9‐boratriptycene, has been generated in solution by selective protodeboronation of the corresponding tetra aryl boron‐ate complex with the strong Brønsted acid HNTf2 . The iptycene core confers enhanced Lewis acidity to 9‐boratriptycene making it unique in terms of structure and reactivity. We studied the stereoelectronic properties of 9‐boratriptycene by quantifying its association with small N and O‐centred Lewis bases, as well as with sterically hindered...
Thu Apr 23, 2020 19:54
The efficient backbone‐directed self‐assembly of cyclic metalla[3]catenanes by the combination of tetrachloroperylenediimide (TCPDI)‐based dinuclear rhodium(III) clips and 4,4′‐diazopyridine or 4,4′‐dipyridylethylene ligands is realized in a single‐step strategy. The topology and coordination geometry of the cyclic metalla[3]catenanes are characterized by NMR spectroscopy, ESI‐TOF‐MS spectrometry, UV‐vis‐NIR spectroscopy and X‐ray diffraction studies. The most remarkable feature of the formed cyclic...
Thu Apr 23, 2020 19:19
The highly conserved HIV‐1 transactivation response element (TAR) binds to the trans‐activator protein Tat and facilitates the viral replication in its latent state. The inhibition of Tat–TAR interactions by selectively targeting TAR RNA has been used as a strategy to develop potent anti‐viral agents. Therefore, HIV‐1 TAR RNA represents a paradigmatic system for therapeutic intervention. Herein, we have employed biotin tagged TAR RNA to assemble its own ligands from a pool of reactive azide‐alkyne...
Thu Apr 23, 2020 17:54
We report the in‐situ tracking of the pyrolysis of a binary molecular cluster [Zn 7 ( μ 3 ‐CH 3 O) 6 (L) 6 ][ZnLCl 2 ] 2 with one brucite disk and two mononuclear fragments (L= mmimp: 2‐methoxy‐6‐((methylimino)‐methyl)phenolate) to porous carbon using TG‐MS from 30 to 900 °C. Following up the spilled gas product during the decomposed reaction of zinc cluster along the temperature rising, and in conjunction with XRD, SEM, BET and other materials characterization, where three key steps...
Thu Apr 23, 2020 17:07
Vacancy defects of catalyst has been extensively studied and proven to be beneficial to various electrocatalytic reactions. However, it remains a great challenge to systematically study the effects of vacancy defects on the electrocatalytic reaction during electrochemical process. Herein, an ultra‐stable three‐dimensional PtCu nanowire networks (NNWs) with ultrafine size, self‐supporting rigid structure, and Cu vacancy defects has been successfully developed. The vacancy defect‐rich PtCu NNWs exhibits...
Thu Apr 23, 2020 17:06
The incorporation of impurity ions or doping is a promising method for controlling the electronic and optical properties and the structural stability of halide perovskite nanocrystals (NCs). Herein, we establish relationships between rare earth ions doping and intrinsic emission of lead‐free double perovskite Cs 2 AgInCl 6 NCs to impart and tune the optical performances in the visible light region. Tb 3+ ions were incorporated into Cs 2 AgInCl 6 NCs and occupied In 3+ sites verified by...
Thu Apr 23, 2020 17:04
The garnet electrolyte presents poor wettability with Li metal, resulting in an extremely large interfacial impedance and drastic growth of Li dendrites. Herein, a novel ultra‐stable conductive composite interface (CCI) consisting of LiySn alloy and Li3N is in‐situ constructed between Li6.4La3Zr1.4Ta0.6O12 (LLZTO) pellet and Li metal by conversion reaction of SnNx with Li metal at 300 ℃. The LiySn alloy as a continuous and robust bridge between LLZTO and Li metal can effectively reduce the LLZTO/Li...
Thu Apr 23, 2020 17:03
Cyanogramide ( 1 ) from marine‐derived Actinoalloteichus cyanogriseus WH1‐2216‐6 features a unique spirooxindole skeleton and exhibits significant bioactivity to efficiently reverse the multiple drug resistance of tumor cells. The biosynthetic gene cluster of 1 was identified and refactored by promoter engineering for heterologous expression in Streptomyces coelicolor YF11, enabling the production of 1 and five new derivatives. Interesting, four of them, including 1 , are identified as...
Thu Apr 23, 2020 17:02
Intrinsic advantages and uniqueness in chirality amplification are exhibited by pillararenes. By combining high affinity for guests, detectable UV absorption, and inducible chirality they can be used for detecting cryptochiral compounds. Abstract The contradiction between the rising demands of optical chirality sensing and the failure in chiral detection of cryptochiral compounds encourages researchers to find new methods for chirality amplification. Inspired by planar chirality and the host–guest...
Thu Apr 23, 2020 15:29
Chemical intuition tells us that pressure increases ordering in most known materials. The discovery of pressure‐induced disorder in double perovskites Y2CoIrO6 and Y2CoRuO6 is in contrast to traditional theories of order–disorder mechanisms and calls for to reconsideration of pressure effects in solid state sciences. Read more in the Research Article by Z. Deng et al. (DOI: https://doi.org/10.1002/anie.20200192210.1002/anie.202001922).
Thu Apr 23, 2020 15:28
Hexagonal boron nitride is an emerging catalyst for oxidative dehydrogenation (ODH) of alkanes to produce olefins with high selectivity and activity. In their Communication (DOI: https://doi.org/10.1002/anie.20200244010.1002/anie.202002440), V. Fung, W. Huang, Z. Wu, and co‐workers report the first direct experimental evidence of gas‐phase methyl radicals (CH3⋅) in propane ODH over boron‐based catalysts. The presence of gas‐phase radicals is shown to be partially responsible for the generation of...
Thu Apr 23, 2020 15:28
“My biggest inspiration is the Chinese puzzle ball. This traditional artwork possesses characteristics desired for scientific study and practical application of materials, and it inspired our hollow multi‐shelled structures …” Find out more about Dan Wang in his Author Profile.
Thu Apr 23, 2020 15:28
Al in: Reaction of the aluminum dialkynyl with B(C6F5)3 proceeds through an intermediate with Al⋅⋅⋅η2‐C≡C side‐on coordination to form the alumole. Some of the alumoles synthesized in this way exhibit an aggregation‐induced emission (AIE) bright yellow fluorescence. Abstract Reaction of the aluminum dialkynyl LAl(CCR)2 (L=N,N‐chelate ligand and R=organic group) with B(C6F5)3 proceeds through an intermediate with Al⋅⋅⋅η2‐C≡C side‐on coordination to form the alumoles (2, 4, 6). A distinctive...
Thu Apr 23, 2020 15:27
The performance of many modern phosphors, such as nitrides, relies on their inherent stabilization of Eu2+ centers, although they are prepared from Eu3+‐based dopants. However, the mechanism of this inherent reduction by the phosphors is unclear. Photoluminescence spectroscopy now shows the reduction is related to color centers at otherwise undesired defects. Abstract Inorganic hosts, such as SrB4O7 or certain nitrides, intrinsically stabilize Eu2+ even when the dopant is an Eu3+‐based precursor...
Thu Apr 23, 2020 15:27
ABSTRACT Proliferative Vasculopathy and Hydranencephaly‐Hydrocephaly syndrome (PVHH, OMIM 225790), also known as Fowler syndrome, is a rare autosomal recessive disorder of brain angiogenesis. PVHH has long been considered to be prenatally lethal. We evaluated the phenotypes of the first three siblings with survival into adulthood, performed a systematic review of the Fowler syndrome literature and delineated genotype‐phenotype correlations using a scoring system to rate the severity of the...
Fri Apr 24, 2020 17:40
Abstract Recently, ADAMTS19 was identified as a novel causative gene for heart valve disease (HVD), affecting mainly the aortic and pulmonary valves. Exome sequencing and data repository (CentoMD) analyses were performed to identify patients with ADAMTS19 variants (two families). A third family was recognized based on cardiac phenotypic similarities and SNP array homozygosity. Three novel loss of function (LoF) variants were identified in six patients from three families. Clinically, all...
Thu Apr 23, 2020 11:51
ABSTRACT Objective The present study focused on investigating levels of oxidative stress, neutrophil elastase (NE) and insulin‐like growth factor‐binding protein 7 (IGFBP7) in oropharyngeal cancers (OC) with the presence and absence of periodontitis. Materials and methods A healthy non‐periodontitis group (H‐NP)(n=20), a systemically healthy chronic periodontitis group (H‐P)(n=20), a non‐periodontitis group with OC (OC‐NP)(n=12), and a chronic periodontitis group with OC (OC‐P)(n=16)...
Fri Apr 24, 2020 16:00
ABSTRACT The current COVID‐19 pandemic influences many areas of social life, medical treatments and the way allergy is performed. Allergen‐specific immunotherapy (AIT) is one of the most important treatment options for IgE‐mediated allergies and is based on immunological effects on the diseased patient
Fri Apr 24, 2020 18:34
Abstract Background Dupilumab is an anti‐IL‐4Rα antibody used in the treatment of patients with moderate‐to‐severe atopic dermatitis (msAD). This study explored the potential benefit of dupilumab in perennial allergic rhinoconjunctivitis (PAR) and perennial allergic asthma (PAA) caused by indoor allergens in adults with msAD. Methods This multicentric, prospective, observational, real‐life study, included adult patients with msAD who had been treated with dupilumab in 16 Italian...
Thu Apr 23, 2020 21:29
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