Oxidative [3+3] cycloadditions constitute an efficient approach for the generation of six‐membered rings. Such a strategy was realized through an electrochemical oxidative coupling of indoles/enamines with active methylene compounds followed by tandem cyclization to generate dihydropyrano[4,3‐b]indoles and 2,3‐dihydrofurans. Abstract Oxidative [3+3] cycloadditions offer an efficient route for six‐membered‐ring formation. This approach has been realized based on an electrochemical oxidative...
Mon May 18, 2020 11:41
Straight shot: A direct γ‐C−H olefination of carboxylic acids and subsequent intramolecular cyclization generates δ‐lactones. Two suitable ligand classes are identified to enable this Pd‐catalyzed transformation that features a broad scope of both reaction partners. The reaction does not require an exogenous directing group and can be performed on a synthetically useful scale. Kinetic studies provide first mechanistic insights. Abstract We report the ligand‐enabled C−H activation/olefination...
Mon May 18, 2020 11:41
Stacked fractals: 2D gold mesh‐like gels with areas of up to 2 cm2 are synthesized via phase boundary gelation. The structures are described as fractals. By variation of experimental details, web thicknesses between 4.1 nm and 14.7 nm. The networks can be stacked or transferred to different substrates. Abstract As there is a great demand of 2D metal networks, especially out of gold for a plethora of applications we show a universal synthetic method via phase boundary gelation which allows the...
Mon May 18, 2020 11:38
In anionic 2, nucleophilic pyrazolate ligand, neutral {Fe(NO)2}10 unit, and [K‐18‐crown‐6‐ether]+ countercation work in concert to promote the capture and nucleophilic activation of CO2 through the assembly of stable 2‐CO2. Relying on one‐electron reduction power of {Fe(NO)2}10 core in anionic complex [(NO)2Fe(MePyrCO2)]−, addition of dicationic Ca2+ further initiates the C−C coupling of activated/reduced CO2 and yields precipitated calcium oxalate. Abstract Continued efforts are made for the...
Mon May 18, 2020 11:38
Like a heat wave: Molecular motor‐like agents with excellent photothermal conversion performance, attributed to highly efficient deactivation through a nonradiative conical intersection (CI) pathway, were combined with a heat shock protein 70 inhibitor for low‐temperature photothermal therapy. Abstract It remains highly challenging to identify small molecule‐based photothermal agents with a high photothermal conversion efficiency (PTCE). Herein, we adopt a double bond‐based molecular motor...
Mon May 18, 2020 11:37
All together now: An intein‐mediated one‐pot ligation enables the semisynthesis of glycosylphosphatidylinositol (GPI)‐anchored proteins. The process works efficiently with denaturated and folded proteins under diverse conditions. This method was applied to the synthesis of a natural GPI‐anchored protein from Plasmodium berghei that exhibits proinflammatory activity in vitro. Abstract Glypiation is a common posttranslational modification of eukaryotic proteins involving the attachment of a glycosylphosphatidylinositol...
Mon May 18, 2020 11:36
C versus P selectivity: Quaternary phosphiranium salts (QPrS) are a fascinating yet underutilized class of phosphorus building blocks with instability and site‐electrophilicity issues. The challenging C‐centered nucleophilic ring opening of these salts, by reaction with aniline derivatives, is now reported and demonstrates the potential synthetic utility of QPrS. Abstract Advances in the field of phosphorus chemistry are documented, by revealing the synthetic utility of previously underutilized...
Mon May 18, 2020 11:35
Cage PAINTings: Fluorescent DNA probes conjugated with a cyanine dye are reductively caged to hydrocyanine, acting as a photoactivatable dark state. The additional dark state from caging lowered the fluorescent background while enabling optically selective activation by total internal reflection illumination. With the aid of high‐density analysis, the imaging speed of conventional DNA‐PAINT was increased by two orders of magnitude, making DNA‐PAINT capable of high‐throughput super‐resolution imaging....
Mon May 18, 2020 11:35
A ribosomal route to ornithine peptides: Genomic predictions in Cyanobacteria suggested untapped capacity for structurally diverse proteusin peptide natural products. Transfer of an orphan pathway into E. coli yielded landornamide A, an ornithine‐containing peptide with rare antiviral activity. Although common in non‐ribosomal peptides, ornithine is a novel post‐translational modification of arginine. Abstract Proteusins are a family of bacterial ribosomal peptides that largely remain hypothetical...
Mon May 18, 2020 11:34
Magnetic Co2Mo3O8@NC‐800 composed of single‐crystal Co2Mo3O8 and ultrathin nitrogen‐rich carbon was synthesized to uncover its OER active sites (Td Co2+ or Oh Co2+). Electrochemical data, magnetism data, and computations suggest that the Td Co2+ atoms (high spin, t23e4) in Co2Mo3O8 act as active sites facilitating the rate‐determining step, forming *OOH to promote the reaction kinetics for OER. Abstract Transition‐metal oxides as electrocatalysts for the oxygen evolution reaction (OER) provide...
Mon May 18, 2020 11:26
Born to be mild: A mild and efficient desymmetrizing protoboration of bis(vinyl)silanes with B2pin2 or Bpin‐Bdan mediated by a (R,R)‐i Pr‐Duphos‐ligated copper catalyst was developed. An array of synthetic versatile but challenging enantioenriched borated organosilanes bearing contiguous silicon and carbonstereocenters were obtained with generally excellent diastereo‐ and enantioselectivity. Abstract The catalytic asymmetric creation of silanes with silicon stereocenters is a long‐sought but...
Mon May 18, 2020 11:16
Attract to plant lattice growth: Imine‐linked covalent organic frameworks (blue) attract organic building blocks on a 2D x−y surface and model C=C bond formation to create 2D sp2 carbon lattices with different topologies (yellow). Frameworks are thus formed that cannot be produced by direct polymerization. The synthesis of such lattices leads to knowledge about π transmission and exciton migration across the 2D lattice. Abstract A strategy is presented for the synthesis of crystalline porous...
Mon May 18, 2020 11:16
A transition‐metal‐free method for the synthesis of α‐branched amines from tertiary carboxamides and lactams with carbon‐centered nucleophiles has been developed. This scalable process relies on the controlled reduction of tertiary amides by NaH/NaI composite, in situ treatment of the resulting anionic hemiaminal with trimethylsilyl chloride, and subsequent coupling with nucleophilic reagents including Grignard reagents and tetrabutylammonium cyanide. Abstract A new method for the synthesis...
Mon May 18, 2020 11:14
Nanospace functions: Nitrogen‐doped polyaromatic capsules were synthesized from metal ions and pyridine‐embedded, bent anthracene‐based ligands. These capsules display unique host–guest interactions, distinct from those of the undoped analogues. Besides the inclusion of Ag+ ions, an absorption change of fullerene C60 and altered emission of a BODIPY dimer are observed upon encapsulation. Moreover, the N‐doped capsule exhibits specific binding abilities toward a natural female and synthetic male hormones....
Mon May 18, 2020 11:08
Two incommensurately modulated nonlinear optical sulfides, Ba2SnS5 and Sr2SnS5, exhibit phase matching behavior and large laser‐induced damage thresholds. The second harmonic generation of Ba2SnS5 at 1570 nm is 1.1‐fold stronger than that of AgGaS2 as it benefits from the positional and occupational modulations. Abstract Structural modulations have been recently found to cause some unusual physical properties, such as superconductivity or charge density waves; however, thus‐induced nonlinear...
Mon May 18, 2020 11:08
Domino reaction: A new monodentate phosphoramidite ligand, Xida‐Phos, was used in the enantioselective Pd‐catalyzed domino Heck carbonylative reaction for the synthesis of oxindoles having β‐carbonyl‐substituted all‐carbon quaternary centers. The reaction was used in the asymmetric synthesis of bioactive hexahydropyrroloindole (HPI) and its dimeric alkaloids. Abstract Reported herein is the development of the first enantioselective monodentate ligand assisted Pd‐catalyzed domino Heck carbonylation...
Mon May 18, 2020 11:07
Gotta catch ′em all: A completely automated, partially polarizable, generic force field for the accurate description of structures and dynamics of large molecules across the periodic table is presented. This method, termed GFN‐FF, combines force‐field speed with almost quantum‐mechanical accuracy. Abstract Modern chemistry seems to be unlimited in molecular size and elemental composition. Metal‐organic frameworks or biological macromolecules involve complex architectures and a large variety...
Mon May 18, 2020 11:01
Made to order: A designed asymmetric assembly creates novel synthetic higher‐order protein assemblies. A symmetric ternary protein complex is formed through stabilizer (red) mediated peptide (green) binding to a scaffold (grey). Modulation of the interface between the peptides (yellow, blue) leads to asymmetric protein self‐sorting. This elucidation of higher‐order protein structures provides insights into protein assembly and the connected role of scaffold proteins. Abstract Cellular signaling...
Mon May 18, 2020 11:01
Inspirational device: A molecularly engineered electrolyzer was constructed for the selective oxidation of glycerol to glyceraldehyde, with a turnover number (TON) of ≈1000 and a Faradaic efficiency (FE) of 83 %, coupled with aqueous CO2 reduction to generate a stoichiometric amount of syngas, with a CO:H2 ratio of 1.25±0.25, an overall TON of 894 and FE of 82 %. Abstract Electrolyzers combining CO2 reduction (CO2R) with organic substrate oxidation can produce fuel and chemical feedstocks with...
Mon May 18, 2020 11:01
Alkoxy radicals generated directly by the activation of alcohol O−H bonds under light‐driven catalytic conditions can be leveraged for the intramolecular hydroetherification of unactivated olefins. This strategy enables productive C−O bond formation from highly reactive alkoxy radical intermediates and accommodates a broad substrate scope with high functional‐group tolerance. PCET=proton‐coupled electron transfer, HAT=hydrogen‐atom transfer. Abstract We report a catalytic, light‐driven method...
Mon May 18, 2020 11:01
Fab‐ulous! A novel small‐molecule‐controlled chimeric antigen receptor T cell (CAR‐T) therapy was developed based on a chemically programmed antibody fragment (Fab) as an on/off switch. As a proof‐of‐concept, a folate‐programmed Fab switch mediated potent and specific eradication of folate‐receptor‐expressing cancer cells by engaging CAR‐T cells in both in vitro and in vivo models of ovarian cancer. Abstract Although macromolecules on cell surfaces are predominantly targeted and drugged with...
Mon May 18, 2020 11:01
All together now: The first synthesis of an ultra‐high‐temperature high‐entropy carbide, (TiNbTaZrHf)C, is reported. These materials are in demand for modern additive manufacturing techniques and might also find application in energy devices such as supercapacitors. Abstract High‐entropy alloys and compounds are becoming an important class of new materials due to their outstanding refractory and high‐temperature properties. However, preparation in bulk quantities and in powder form via classical...
Mon May 18, 2020 11:00
Re‐Arrangement silicissimo! Vinylcyclopropanes (VCPs) undergo a formal (5+1) cycloaddition when reacted with in situ generated silylium ions. The bond reorganization is connected to an aryl migration to eventually yield a silacyclohexane derivative which is regioisomeric to the expected product. Reaction mechanisms that rationalize the formation of the major and minor products are presented based on a series of control experiments and quantum‐chemical calculations. Abstract A transition‐metal‐free...
Mon May 18, 2020 11:00
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 reaction conditions, including milling time, added reductant to accelerate the polymerization, and milling frequency were optimized. Monomer conversion and polymer molecular weight evolution were monitored over time using 1H NMR spectroscopy and size exclusion chromatography, respectively, and...
Sun May 17, 2020 22:00
New Findings What is the central question of this study? Splenic contractions occur in response to apnoea‐induced hypoxia with and without face immersion in water. However, the splenic responses to a series of static or dynamic apnoeas with whole body water immersion in non‐divers (ND) and elite breath‐hold divers (EBHD) are unknown. What is the main finding and its importance? Static and dynamic apnoeas were equally effective in stimulating splenic contractions across ND and EBHD....
Mon May 18, 2020 17:50
New Findings What is the central question of this study? We assessed the utility of a novel metric for quantifying ventilatory acclimatization to high altitude, derived from differential ascent and descent steady‐state cardiorespiratory variables (i.e., hysteresis). Furthermore, we aimed to investigate whether the magnitude of cardiorespiratory hysteresis was associated with the development of acute mountain sickness. What is the main finding and its importance? Hysteresis in steady‐state...
Mon May 18, 2020 17:49
Acute appendicitis is the most common non-gynecological emergency during pregnancy. The diagnosis of appendicitis during pregnancy is challenging due to changes in both physiological and laboratory variables. ...
Mon May 18, 2020 03:00
Rejuvenation Research, Ahead of Print.
Mon May 18, 2020 10:00
Abstract Potential long‐term consequences of hypnotics remain controversial. We used the prospective Swedish National March Cohort, a study based on 41,695 participants with a mean follow‐up duration of 18.9 years. Logistic regression models and Cox proportional hazards models with attained age as timescale were used to assess associations of hypnotic use with short‐ and long‐term mortality. The proportion of subjects who initiated or discontinued hypnotic use during follow‐up was substantial. All...
Mon May 18, 2020 13:12
The Journal of Antibiotics, Published online: 19 May 2020; doi:10.1038/s41429-020-0314-5Epipolythiodiketopiperazine and trichothecene derivatives from the NaI-containing fermentation of marine-derived Trichoderma cf. brevicompactum
Tue May 19, 2020 03:00
Tue May 19, 2020 03:00
Fri May 15, 2020 03:00
Identifying Patch Types Using Movement Data from Artisanal Fishers from the Commonwealth of Dominica
Current Anthropology, Ahead of Print.
Mon May 18, 2020 06:55
The coexistence of two morphologically different tumors attached to each other creates a very rare type of tumor called a collision tumor. Collision tumors containing pituitary adenoma–sellar meningioma have o...
Tue May 19, 2020 03:00
Venkatesh Hosur Ananthashayana, Manisha Jana, Sumeet S Malapure, Arun K GuptaIndian Journal of Cancer 2020 57(2):209-211 Intracranial parenchymal calcification has both benign and malignant etiologies. Calcifications by malignant etiologies are comparatively rare. Malignant calcification has numerous causes. Calcified brain metastasis from osteosarcoma is one such cause. We present histopathologically confirmed intracranial calcified metastasis in a 10 year old girl. This girl had received treatment...
Mon May 18, 2020 00:00
The Tata Memorial Centre COVID-19 Working Group Indian Journal of Cancer 2020 57(2):123-128
Mon May 18, 2020 00:00
Tejal Abasaheb Khande, Avinash R Joshi, Siddhi Gaurish Sinai Khandeparkar, Maithili M Kulkarni, Bageshri P Gogate, Aniket R Kakade, Piyush D Sahu, Chaitnya D KhillareIndian Journal of Cancer 2020 57(2):190-197 Background: Breast cancer (BCA) is the second most common cancer among women in India and accounts for 7% of global burden of BCA. The axillary lymph node status is an independent prognostic factor. The combined estrogen receptor (ER), progesterone receptor (PR), and HER2/neu biomarker...
Mon May 18, 2020 00:00
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