Τετάρτη 6 Νοεμβρίου 2019


The Impact of Conductive Hearing Loss on Balance
Abstract Background Balance is a complex process involving the coordinated activities of multiple sensory, motor and biomechanical components. Balance function may be disturbed in subjects suffering from hearing loss but the impairment has been attributed to the pathology underlying the hearing loss. Aim The purpose of the study was to investigate the possible interference of simulated conductive hearing loss with the ability to maintain postural balance. Methods Twenty normal hearing...
Wiley: Clinical Otolaryngology: Table of Contents
Wed Nov 06, 2019 19:20
Torsional and Bending Properties of V Taper 2H, ProTaper NEXT, NRT, and One Shape
Nickel-titanium (NiTi) rotary files have enabled efficient root canal preparations that maintain the canal center with fewer aberrations compared to hand files. However, NiTi rotary files are susceptible to fracture, which can thereby compromise root canal treatment. Therefore, NiTi files have been developed to enhance fracture resistance by modifying design and thermal treatment. The objective of this study was to compare the torsional fatigue resistance and bending resistance of NiTi files manufactured...
BioMed Research International
08:05
Prevalence and Genetic Identification of Three Entamoeba Species in Pigs in Southeastern China
Parasitic Entamoeba spp. can infect many classes of vertebrates including humans and pigs. Entamoeba suis and zoonotic Entamoeba polecki have been identified in pigs, and swine are implicated as potential reservoirs for Entamoeba histolytica. However, the prevalence of Entamoeba spp. in pigs in southeastern China has not been reported. In this study, 668 fecal samples collected from 6 different regions in Fujian Province, southeastern China, were analyzed to identify three Entamoeba species by nested...
BioMed Research International
05:05
Delayed Rectifier K+-Channel Is a Novel Therapeutic Target for Interstitial Renal Fibrosis in Rats with Unilateral Ureteral Obstruction
Background. Delayed rectifier K+-channel, Kv1.3, is most predominantly expressed in T-lymphocytes and macrophages. In such leukocytes, Kv1.3-channels play pivotal roles in the activation and proliferation of cells, promoting cellular immunity. Since leukocyte-derived cytokines stimulate fibroblasts to produce collagen fibers in inflamed kidneys, Kv1.3-channels expressed in leukocytes would contribute to the progression of tubulointerstitial renal fibrosis. Methods. Male Sprague-Dawley rats that underwent...
BioMed Research International
05:05
Carvedilol Inhibits Angiotensin II-Induced Proliferation and Contraction in Hepatic Stellate Cells through the RhoA/Rho-Kinase Pathway
Aim. Carvedilol is a nonselective beta-blocker used to reduce portal hypertension. This study investigated the effects and potential mechanisms of carvedilol in angiotensin II- (Ang II-) induced hepatic stellate cell (HSC) proliferation and contraction. Methods. The effect of carvedilol on HSC proliferation was measured by Cell Counting Kit-8 (CCK-8). Cell cycle progression and apoptosis in HSCs were determined by flow cytometry. A collagen gel assay was used to confirm HSC contraction. The extent...
BioMed Research International
04:05
Predictive Scoring and Risk Factors of Early Recurrence after Percutaneous Endoscopic Lumbar Discectomy
Purpose. To predict the early recurrence after full endoscopic lumbar discectomy, we analyzed factors related to demographic factor anatomical factors, operative method, and postoperative management, and predicted the possibility of recurrence according to the scoring system. Materials and Methods. In this prospective study, we enrolled 300 patients who underwent 1 out of 3 surgical procedures. The patients were randomized into one of the following groups: group A (), transforaminal inside-out approach;...
BioMed Research International
02:05
Experimental Resin-Based Monoblock Endodontic Obturation System
Objective. The aim of the present study was to characterize a novel resin-based monoblock endodontic obturation system consisting of a polymeric cone and a resin-based endodontic sealer. Methods. The preliminary tests performed for the experimental cone were as follows: cohesive strength, dimensional stability, standardization of the diameter and taper, calcium ion release, and radiopacity, for the characterization of the experimental sealer, film thickness and flow tests were performed. Tests were...
BioMed Research International
02:05
In Situ Endoscopic Analysis of Vascular Supply and Regenerated Alveolar Bone in β-TCP Grafted and Ungrafted Postextraction Sites before Implant Placement: A Prospective Case Control Study
Background. Endoscopy has seen a significant development over recent years in various medical fields with its application expanding from the support of minimal invasive surgery to in situ imaging. In this context, the application of endoscopic techniques to assess the quality of the regenerated bone in situ in the drill hole before implant placement is an appealing approach. Aim. The aim of this study was to use short distance support immersion endoscopy (SD-SIE) to compare the quality of regenerated...
BioMed Research International
Wed Nov 06, 2019 19:05
Origin, Genetic Diversity, and Population Structure of Rabbits (Oryctolagus cuniculus) in Kenya
To evaluate the origin, genetic diversity, and population structure of domesticated rabbits in Kenya, a 263-base pair region of mtDNA D-loop region of 111 rabbits sampled from Kakamega, Vihiga, and Bungoma counties in the western region, Laikipia and Nyandarua counties in the central region, and Kitui, Machakos, and Makueni in the eastern region of the country were analyzed. The average haplotype (0.40702) and nucleotide (0.01494) diversities observed were low, indicating low genetic diversity of...
BioMed Research International
Wed Nov 06, 2019 19:05
Tumor Mutational Burden and Genomic Alterations in Chinese Small Cell Lung Cancer Measured by Whole-Exome Sequencing
Purpose. Studies on genetic alterations of the heterogenous small cell lung cancer (SCLC) are rare. We carried out the present study to clarify the genomic alterations and TMB levels of Chinese SCLC patients by whole-exome sequencing. Materials and Methods. Whole-exome sequencing by next-generation sequencing technique was implemented on twenty SCLC samples. Significant somatic mutations and copy number variations were screened, followed by comparison with the data extracted from COSMIC. Besides,...
BioMed Research International
Wed Nov 06, 2019 19:05
Chromosomal Aberrations in Pediatric Patients with Developmental Delay/Intellectual Disability: A Single-Center Clinical Investigation
Introduction. Chromosomal microarray analysis (CMA) has currently been considered as the first-tier genetic test for patients with developmental delay/intellectual disability (DD/ID) in many countries. In this study, we performed an extensive assessment of the value of CMA for the diagnosis of children with ID/DD in China. Methods. A total of 633 patients diagnosed with DD/ID in West China Second University Hospital, Sichuan University, were recruited from January 2014 to March 2019. The patients...
BioMed Research International
Wed Nov 06, 2019 19:05
Glypican-3 Enhances Reprogramming of Glucose Metabolism in Liver Cancer Cells
Glypican-3(GPC3) is a transmembrane protein which has been found to be frequently overexpressed on the surfaces of liver cancer (LC) cells, which contributes to both the growth and metastasis of LC cells. Recently, the expression of GPC3 has been reported to be inversely associated with glucose metabolism activity in LC patients, suggesting that GPC3 may play a role in the regulation of glucose metabolism in LC. However, the role of GPC3 in glucose metabolism reprogramming, as well as in LC cell...
BioMed Research International
Wed Nov 06, 2019 11:05
Dihydroartemisinin Protects against Dextran Sulfate Sodium-Induced Colitis in Mice through Inhibiting the PI3K/AKT and NF-κB Signaling Pathways
Ulcerative colitis is a common inflammatory bowel disease, and the activation of thePI3K/AKT and NF-κB signaling pathways plays a pivotal role in its pathogenesis. Dihydroartemisinin (DHA) is a widely used antimalarial drug and has shown anticancer effect partially through inhibiting the activation of PI3K/AKT and NF-κB. This study aimed to investigate the effect of dihydroartemisinin on ulcerative colitis and its mechanism. Adult male C57 mice were subjected to 3.0% dextran sulfate sodium (DSS)...
BioMed Research International
Wed Nov 06, 2019 10:05
Antimicrobial Resistance Factors of Extended-Spectrum Beta-Lactamases Producing Escherichia coli and Klebsiella pneumoniae Isolated from Cattle Farms and Raw Beef in North-West Province, South Africa
Background. Extended spectrum beta-lactamases (ESBLs) producing Enterobacteriaceae cause severe infections in humans which leads to complicated diseases. There is increasing evidence that cattle contribute to the development and spread of multidrug resistant pathogens and this raises public health concern. Despite this, data on the concurrence of ESBL producing pathogens in cattle, especially in the North-West province are rare. Therefore, the aim of the present study was to isolate, identify and...
BioMed Research International
Wed Nov 06, 2019 09:05
Bone Marrow-Derived Mesenchymal Stem Cell Potential Regression of Dysplasia Associating Experimental Liver Fibrosis in Albino Rats
Objectives. Assessing the therapeutic efficacy of superparamagnetic iron oxide nanoparticles (SPIO) labeled bone marrow-derived mesenchymal stem cells (BM-MSCs) on experimental liver fibrosis and associated dysplasia. Materials and Methods. MSCs were obtained from 10 male Sprague-Dawley rats while 50 female rats were divided into control (CG), liver fibrosis (CCL4, intraperitoneal injection of CCl4 for 8 weeks), and CCL4 rats treated with SPIO-labeled MSCs (MSCs/CCl4) with and without continuing...
BioMed Research International
Wed Nov 06, 2019 09:05
Diabetes Mellitus among Adult Tuberculosis Patients Attending Tuberculosis Clinics in Eastern Ethiopia
Background. Developing countries are suffering from the previously existing infectious diseases and alarmingly growing burden of noncommunicable diseases like diabetes mellitus. There is increased speculation that diabetes mellitus might attribute to high infectious diseases burden, such as tuberculosis. The global importance of diabetes mellitus as a tuberculosis-risk factor is still not a well-established fact. Thus, we conducted this study to determine the prevalence of diabetes mellitus and its...
BioMed Research International
Wed Nov 06, 2019 09:05
Association between ACE A240T polymorphism and cancer risk: a meta-analysis
Journal of International Medical Research, Ahead of Print.
SAGE Publications Ltd: Journal of International Medical Research: Table of Contents
07:02
Mature cystic teratoma arising from the fimbrial end of the left fallopian tube. a case report
Journal of International Medical Research, Ahead of Print.
SAGE Publications Ltd: Journal of International Medical Research: Table of Contents
Tue Nov 05, 2019 09:43
Comparative Effect of Glass Fiber and Nano‐Filler Addition on Denture Repair Strength
Abstract Purpose : To evaluate and compare the effects of glass fiber (GF), Zirconium oxide nanoparticles (nano‐ZrO2), and silicon dioxide nanoparticles (nano‐SiO2) addition on the flexural strength and impact strength of repaired denture base material. Materials and Methods : Heat‐polymerized acrylic resin specimens were fabricated. All specimens were sectioned centrally and beveled creating 2.5 mm repair gap except for 10 controls. Specimen grouping (n = 10/group) was done according to...
Journal of Prosthodontics
Wed Nov 06, 2019 19:37
Utility of 8-Aminoquinolines in Malaria Prophylaxis in Travelers
Abstract Purpose of Review To review the current status of 8-aminoquinolines in the prophylaxis of malaria among travelers, in light of the recent approval of tafenoquine. Recent Findings Primaquine continues to provide excellent primary prophylaxis against all Plasmodium species. Tafenoquine provides similarly good prophylaxis, with the benefit...
Latest Results for Current Infectious Disease Reports
02:00
Fractional CO2 laser plus topical antifungal versus fractional CO2 laser versus topical antifungal in the treatment of onychomycosis
Abstract Introduction Onychomycosis is an important medical disorder affecting both patients’ health and quality of life. Objective This study was done to compare the efficacy of CO2 laser in combination with topical tioconazole versus CO2 laser only versus topical tioconazole alone in onychomycosis. Patients and methods A total of 120 patients with onychomycosis were randomly assigned to 3 groups. Group A patients were treated with fractional CO2 laser followed by topical tioconazole...
Wiley: Dermatologic Therapy: Table of Contents
Wed Nov 06, 2019 16:34
Intralesional rituximab salvages refractory scalp lesions in a case of pemphigus vulgaris
Wiley: Dermatologic Therapy: Table of Contents
Wed Nov 06, 2019 22:33
Intensivist coverage and patient outcomes
Latest Results for Journal of Anesthesia
02:00
Transcriptome‐wide association study reveals candidate causal genes for lung cancer
We have recently completed the largest GWAS on lung cancer including 29,266 cases and 56,450 controls of European descent. The goal of this study has been to integrate the complete GWAS results with a large‐scale expression quantitative trait loci (eQTL) mapping study in human lung tissues (n=1,038) to identify candidate causal genes for lung cancer. We performed transcriptome‐wide association study (TWAS) for lung cancer overall, by histology (adenocarcinoma, squamous cell carcinoma, small cell...
International Journal of Cancer
Wed Nov 06, 2019 18:33
Molecular Profiles of BRCA1‐Associated Ovarian Cancer Treated by Platinum‐Based Therapy: Analysis of Primary, Residual and Relapsed Tumours
This study aimed to analyze the evolution of molecular portraits of BRCA1‐driven ovarian cancer (OC) during treatment. BRCA1 loss‐of‐heterozygosity status (LOH) and exome profiles were investigated in serial OC samples from 13 patients, which included primary tumours (n = 11) obtained before neoadjuvant therapy (NACT) or at primary debulking surgery (PDS), residual post‐NACT cancer tissues (n = 13) and tumour relapses (16 samples from 13 patients). Loss of the wild‐type BRCA1 allele was detected...
International Journal of Cancer
Wed Nov 06, 2019 17:37
High‐risk stage III colon cancer patients identified by a novel 5‐gene mutational signature are characterized by up‐regulation of IL‐23A and gut bacterial translocation of the tumor microenvironment
The heterogeneities of colorectal cancer (CRC) lead to staging inadequately of patients' prognosis. Here, we performed a prognostic analysis based on the tumor mutational profile and explored the characteristics of the high‐risk tumors. We sequenced 338 colorectal carcinomas as the training dataset, constructed a novel 5‐gene (SMAD4, MUC16, COL6A3, FLG, and LRP1B) prognostic signature, and validated it in an independent dataset from The Cancer Genome Atlas (TCGA). Kaplan‐Meier and Cox regression...
International Journal of Cancer
Wed Nov 06, 2019 17:33
Pre‐ and Post‐ Diagnosis Smoking and Survival Following Diagnosis with Ovarian Cancer
Little is known about the influence of pre‐ and post‐diagnosis smoking and smoking cessation on ovarian cancer survival. We investigated this relationship in two prospective cohort studies, the Nurses' Health Study (NHS) and NHSII. Analyses included 1279 women with confirmed invasive, stage I‐III epithelial ovarian cancer. We used Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for ovarian cancer‐specific mortality by smoking status, adjusting...
International Journal of Cancer
Wed Nov 06, 2019 17:24
Consumption of sugar‐sweetened and artificially‐sweetened soft drinks and risk of cancers not related to obesity
Consumption of sugary drinks increases the risk of obesity. Previously we reported a positive association between sugar‐sweetened soft drink consumption and obesity‐related cancer but this association was not fully explained by obesity; in contrast, we found no association for consumption of artificially‐sweetened soft drinks. Our aim was to determine whether the consumption of sugar‐sweetened or artificially‐sweetened soft drinks was associated with cancers other than those currently identified...
International Journal of Cancer
Wed Nov 06, 2019 17:19
Association of Common Variants in HNF1A Gene with Serum AFP Level in Healthy Chinese Individuals and HCC Patients
Although alpha-fetoprotein (AFP) is a widely used tumor marker in hepatocellular carcinoma (HCC), 40% of newly diagnosed patients do not have an elevated AFP level. Research has revealed that mutations in the HNF1A binding site of the AFP gene promoter cause significantly elevated serum AFP levels in patients with hereditary persistence of AFP. This study investigated the relationship between HNF1A genetic variants and serum AFP levels. We examined the association between the HNF1A-rs1169288 (A/C),...
Disease Markers
07:05
Whole-Genome Sequencing Identifies the Egl Nine Homologue 3 (egln3/phd3) and Protein Phosphatase 1 Regulatory Inhibitor Subunit 2 (PPP1R2P1) Associated with High-Altitude Polycythemia in Tibetans at High Altitude
Background. The hypoxic conditions at high altitudes are great threats to survival, causing pressure for adaptation. More and more high-altitude denizens are not adapted with the condition known as high-altitude polycythemia (HAPC) that featured excessive erythrocytosis. As a high-altitude sickness, the etiology of HAPC is still unclear. Methods. In this study, we reported the whole-genome sequencing-based study of 10 native Tibetans with HAPC and 10 control subjects followed by genotyping of selected...
Disease Markers
04:05
PI3K/AKT Signaling in Breast Cancer Molecular Subtyping and Lymph Node Involvement
Lymph node metastatic involvement persists to be among the most important predictors of recurrence and survival in breast carcinoma (BC). This study is aimed at investigating possible gene expression differences in primary BC between patients with or without lymph node involvement at the time of diagnosis. In a retrospective study, we investigated the potential prognostic role of 9 candidate biomarkers at the mRNA level in a cohort of 305 breast cancer patients, 151 lymph node-negative (LN-) and...
Disease Markers
Wed Nov 06, 2019 16:15
The Involvement of HLA Class II Alleles in Multiple Sclerosis: A Systematic Review with Meta-analysis
Multiple Sclerosis (MS) displays a heterogeneous clinical onset and progression, which are mostly unpredictable, but demyelination of the central nervous system (CNS) leads to substantial deficits of sensory, motor, autonomic, and neurocognitive functions. Considering all genetic studies on MS, including the advanced genome-wide association studies, the risk linked to HLA alleles remains the highest among other susceptibility genetic variants. However, given the genetic variability of HLA alleles...
Disease Markers
Wed Nov 06, 2019 15:30
Metal artifact reduction algorithm for image quality improvement of cone-beam CT images of medium or large cerebral aneurysms treated with stent-assisted coil embolization
Abstract Purpose The aim of the present study was to assess image quality improvement using a metal artifact reduction (MAR) algorithm in cases of medium or large cerebral aneurysms treated with stent-assisted coil embolization (SAC), and to analyze factors associated with the usefulness of the MAR algorithm. Methods We retrospectively evaluated the cone-beam...
Neuroradiology
02:00
Silent susceptibility-weighted angiography to detect hemorrhagic lesions in the brain: a clinical and phantom study
Abstract Purpose To compare the effectiveness of silent susceptibility-weighted angiography (sSWAN), a new imaging technique with lower acoustic noise, with conventional susceptibility-weighted angiography (cSWAN) in the detection of intracranial hemorrhagic lesions. Methods We measured the acoustic and background noise during sSWAN and cSWAN imaging and...
Neuroradiology
Wed Nov 06, 2019 02:00
Upregulation of Circular RNA Itchy E3 Ubiquitin Protein Ligase Inhibits Cell Proliferation and Promotes Cell Apoptosis Through Targeting MiR-197 in Prostate Cancer
Technology in Cancer Research &Treatment, Volume 18, Issue , January-December 2019. Objective:This study aimed to investigate the effect of circular RNA itchy E3 ubiquitin protein ligase on cell proliferation and apoptosis and to explore its target micro-RNAs in prostate cancer cells.Methods:Circular RNA itchy E3 ubiquitin protein ligase expression in human prostate cancer cells and normal prostate epithelial cells was determined by real time-quantitative polymerase chain reaction assay. Circular...
SAGE Publications Inc: Technology in Cancer Research & Treatment: Table of Contents
07:00
Does host socio-spatial behavior lead to a fine-scale spatial genetic structure in its associated parasites?
Authors: Elodie Portanier, Mathieu Garel, Sébastien Devillard, Jeanne Duhayer, Marie-Thérèse Poirel, Hélène Henri, Corinne Régis, Daniel Maillard, Elizabeth Redman, Christian Itty, Patricia Michel and Gilles Bourgoin.<br />Parasite Vol. 26 , page 64<br />Published online: 07/11/2019<br /> Keywords: Ovis gmelini musimon × Ovis sp. ; Host-parasite co-structure ; Population genetics ; Nematode ; Mouflon ; Haemonchus contortus.<img src="http://feeds.feedburner.com/~r/edp_parasite/~4/K6L-jZafKvU"...
Parasite
02:00
Programming DNA Nanoassembly for Enhanced Photodynamic Therapy
Photodynamic therapy (PDT) has extraordinary promise for the treatment of many cancers. Yet, its clinical progress is impaired by the intrinsic hypoxic tumor microenvironment that limits PDT efficacy and the safety concern associated with biological specificity of photosensitizers or vehicles. Here, we demonstrate that rationally designed DNA nanosponges can load and delivery photosensitizer effectively, target tumor precisely, and relieve hypoxia‐associated resistance remarkably to enhance the...
Angewandte Chemie International Edition
Wed Nov 06, 2019 17:09
Total Synthesis of (+)‐6‐epi‐Ophiobolin A
The ophiobolin sesterterpenes are notable plant pathogens, which have recently elicited significant chemical and biological attention due to their intriguing carbogenic frameworks, reactive functionality, and emerging anticancer profiles. Herein we report a total synthesis of (+)‐6‐epi‐ophiobolin A in 14 steps, a task which addresses construction of the synthetically challenging spirocyclic tetrahydrofuran motif as well as several other key stereochemical problems. This work demonstrates a streamlined...
Angewandte Chemie International Edition
Wed Nov 06, 2019 22:12
Palladium–Borane Cooperation: Evidence for an Anionic Pathway and Its Application to Catalytic Hydro‐/Deutero‐dechlorination
A palladium–borane dance: An anionic reaction pathway involving hydride insertion into a Pd→B bond, C−Cl bond activation by an anionic Pd0 species, and B‐assisted C−H bond formation has been discovered and leveraged into catalysis of hydro‐/deutero‐dechlorination. The boron acts as an acceptor towards Pd via the Pd→B interaction (see figure), but as a donor in the Pd0 borohydride thanks to B‐H‐Pd bridging. Abstract Metal–Lewis acid cooperation provides new opportunities in catalysis. In this...
Angewandte Chemie International Edition
Wed Nov 06, 2019 22:00

Promoter activation in Δhfq mutants as an efficient tool for specialized metabolite production enabling direct bioactivity testing
Natural products (NPs) from microorganisms have been important sources for discovering new therapeutic and chemical entities. While their corresponding biosynthetic gene clusters (BGCs), in general, can be easily identified by gene‐sequence‐similarity‐based bioinformatics strategies, the actual access to these NPs for structure elucidation and bioactivity testing remains difficult, time‐consuming and costly. Deletion of the gene encoding the RNA chaperone, Hfq, that often affects virulence in different...
Angewandte Chemie International Edition
Wed Nov 06, 2019 20:04
Controllable Si‐C Bond Activation Enables Stereocontrol in Palladium‐catalyzed [4+2] Annulation of Cyclopropenes with Benzosilacyclobutanes
A novel and unusual palladium‐catalyzed [4+2] annulation of cyclopropenes with benzosilacyclobutanes is reported. This reaction was completed through chemoselective Si‐C(sp 2 ) bond activation synergized with ring expansion/insertion of cyclopropenes for the formation of new C(sp 2 )‐C(sp 3 ) and Si‐C(sp 3 ) bonds. An array of newly elusive bicyclic skeleton with high strain, sila‐bicyclo[4.1.0]heptanes, was formed with good yields and excellent diastereoselectivity under mild conditions....
Angewandte Chemie International Edition
Tue Nov 05, 2019 19:11
Yellow Circularly Polarized Luminescence from C1‐Symmetrical Copper(I) Complexes
The synthesis of chiral C1‐symmetrical copper(I) complexes supported by chiral carbene ligands is described. These complexes are yellow emitters with modest quantum yields. Circularly polarized luminescence (CPL) spectra show a polarized emission band with dissymmetry factors | g lum | = 1.2 x 10 −3 . These complexes represent the first reported examples of molecular copper(I) complexes exhibiting circularly polarized luminescence. In contrast with most CPL emitting molecules which possess either...
Angewandte Chemie International Edition
Tue Nov 05, 2019 19:09
Self‐Immolative Activation of β–galactosidase Responsive Probes for In Vivo MR Imaging in Mouse Models"
Our lab has developed a new series of self‐immolative MR agents for the rapid detection of enzyme activity in mouse models expressing β‐galactosidase (β‐gal). We investigated two molecular architectures to create agents that detect β‐gal activity by modulating the coordination of water to Gd(III). The first is an intermolecular approach, wherein we designed several structural isomers to maximize coordination of endogenous carbonate ions. The second involves an intramolecular mechanism for q modulation....
Angewandte Chemie International Edition
Tue Nov 05, 2019 19:08
Enantioselective Total Synthesis of Cymoside via a Bioinspired Oxidative Cyclization of a Strictosidine Derivative
The first total synthesis of the caged monoterpene indole alkaloid cymoside is reported. This natural product displays a unique hexacyclic‐fused skeleton whose biosynthesis implies an early oxidative cyclisation of strictosidine. Our approach to the furo[3,2‐ b ]indoline framework relied on an unprecedented biomimetic sequence which started by the diastereoselective oxidation of the indole ring into a hydroxyindolenine which triggered the addition of an enol ether and was followed by the trapping...
Angewandte Chemie International Edition
Tue Nov 05, 2019 18:51
Direct imaging of atomically dispersed Mo enables locating Al in the framework of zeolite ZSM‐5
Zeolites often act as host materials to encapsulate guest molecules to enrich their functions and applications, particularly in heterogeneous catalysis. Unfortunately, directly imaging guest molecules residing in the intact microporous structure of a zeolite has long been a challenge. Here, we report that integrated differential phase‐contrast scanning transmission electron microscopy (iDPC‐STEM) is capable of directly probing guest molecules in zeolites, due to its sufficient and interpretable image...
Angewandte Chemie International Edition
Tue Nov 05, 2019 18:11
Dual‐enhanced Gold Nanocluster Electrochemiluminescence: Electrocatalytic Excitation and Aggregation‐induced Emission
Ligand‐protected gold nanoclusters (AuNCs) have emerged as a new class of electrochemiluminescence (ECL) luminophores for their interesting catalytic and emission properties, although their quantum yield ( Φ ECL ) in aqueous medium is low with a poor mechanistic understanding of the ECL process. Herein, we communicate that drying AuNCs on electrodes enabled both enhanced electrochemical excitation by an electrocatalytic effect, and enhanced emission by aggregation‐induced ECL (AIECL) for 6‐aza‐2‐thiothymine...
Angewandte Chemie International Edition
Tue Nov 05, 2019 17:45
Single chromium atoms supported on titanium dioxide nanoparticles for synergic catalytic methane conversion under mild condition
Direct conversion of methane to value‐added chemicals with high selectivity under mild conditions remains a great challenge in catalysis. Herein, we report a new kind of single chromium atoms supported on titanium dioxide nanoparticles as an efficient heterogeneous catalyst for direct methane oxidation to C1 oxygenated products with H2O2 as oxidant under mild condition. The highest yield for C1 oxygenated products can be reached as 57.9 mol/molCr with selectivity of around 93% at 50ºC for 20 h, which...
Angewandte Chemie International Edition
Tue Nov 05, 2019 17:42
Frontispiece: ZIF‐8 Membrane Separation Performance Tuning by Vapor Phase Ligand Treatment
Gas Separation In their Communication on https://doi.org/10.1002/anie.201909490page 16390 ff., K. Eum, M. Tsapatsis et al. describe the separation of oxygen from air by modified ZIF membranes. The permeation properties of the membranes are reversible and can be tailored to suit their application.
Angewandte Chemie International Edition
Mon Nov 04, 2019 22:49
Sequence‐Dependent Stereodivergent Allylic Alkylation/Fluorination Reaction of Acyclic Ketones
The stereodivergent Ir‐catalyzed allylic alkylation and fluorination of acyclic ketones is described. α ‐Pyridyl‐ α ‐fluoroketones with vicinal tertiary and quaternary stereocenters were obtained in moderate to excellent yields and stereoselectivities. Distinct from the known stereodivergent synthesis where two different chiral catalysts are required in general, herein we report a sequence‐dependent stereodivergent synthesis. With only one single chiral Ir catalyst, all four possible stereoisomers...
Angewandte Chemie International Edition
Wed Nov 06, 2019 19:06
Blue Light Emitting Defective Nanocrystals Composed of Earth‐Abundant Elements
Copper‐based ternary (I‐III‐IV) chalcogenide nanocrystals (NCs) are compositionally‐flexible semiconductors that do not contain Lead (Pb) or Cadmium (Cd). Cu‐In‐S NCs are the dominantly studied member of this important materials class and have been reported to contain optically‐active defect states. However, there are minimal reports of In‐free compositions that exhibit efficient PL. Here, we report a novel solution‐phase synthesis of ~4 nm defective nanocrystals (DNCs) composed of Copper, Aluminum,...
Angewandte Chemie International Edition
Wed Nov 06, 2019 19:05
Supramolecular Surface Charge Regulation in Ionic Covalent Organic Nanosheets for Reversible Exfoliation and Controlled Bacterial Growth
Poor control on the exfoliation of covalent organic frameworks (COFs) remains a disadvantage for their application as two‐dimensional (2D) nanosheets. An equally important problem that needs attention is the reversible control on the available surface charges on COF. Herein, we report an efficient strategy for the reversible exfoliation, re‐stacking and surface charge control of propidium iodide‐based ionic covalent organic framework (iCOF), PI‐TFP, using cucurbit[7]uril (CB[7]) induced molecular...
Angewandte Chemie International Edition
Wed Nov 06, 2019 18:40
Syntheses of atypically fluorinated peptidyl macrocycles via sequential vinylic substitutions
Small peptides containing combinations of cysteine, tyrosine, histidine and serine residues react with octafluorocyclopentene (OFCP) to afford atypically structured macrocycles via successive vinylic substitutions. The reactions proceed rapidly in air at 0 ˚C and are tolerant of spectating tryptophan, asparagine, glutamine and threonine residues. Hexapeptides of consensus sequence YXCXXC displace four fluorine atoms from OFCP to generate fluorinated macrobicyclic compounds that display dual turn...
Angewandte Chemie International Edition
Wed Nov 06, 2019 18:36
Nickel‐Catalyzed 1,2‐Diarylation of Alkenyl Carboxylates: A Gateway to 1,2,3‐Trifunctionalized Building Blocks
A nickel‐catalyzed conjunctive cross‐coupling of alkenyl carboxylic acids, aryl iodides, and aryl/alkenyl boronic esters is reported. The reaction delivers the desired 1,2‐diarylated and 1,2‐arylalkenylated products with excellent regiocontrol. To demonstrate the synthetic utility of the method, a representative product is prepared on gram scale and then diversified to eight 1,2,3‐trifunctionalized building blocks using two‐electron and one‐electron logic. Using this method, three routes toward bioactive...
Angewandte Chemie International Edition
Wed Nov 06, 2019 18:14
Rapid syntheses of (−)‐FR901483 and (+)‐TAN1251C enabled by complexity‐generating photocatalytic olefin hydroaminoalkylation
We report a common strategy to facilitate the syntheses of the polycyclic alkaloids (−)‐FR901483 ( 1 ) and (+)‐TAN1251C ( 2 ). A divergent synthetic strategy provides access both natural products through a pivotal spirolactam intermediate ( 3 ), which can be accessed on a gram‐scale. A photocatalytic olefin hydroaminoalkylation brings together three readily available building blocks and forges the majority of the carbon framework present in 1 and 2 in a single operation, leading to concise...
Angewandte Chemie International Edition
Wed Nov 06, 2019 18:00
Arene Trifunctionalization with Highly Fused Ring Systems through a Domino Aryne Nucleophilic and Diels–Alder Cascade
3 in 1: A convenient and efficient domino aryne process was developed under transition‐metal‐free conditions to afford tetra‐ and pentacyclic ring systems. Chemoselective control at both the 1,2‐aryne and 2,3‐aryne stages enabled three new chemical bonds, namely one C−N and two C−C bonds, and two benzofused rings to be constructed concomitantly. Abstract A convenient and efficient domino aryne process was developed under transition‐metal‐free conditions to generate a range of tetra‐ and pentacyclic...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:07
Flexible Amalgam Film Enables Stable Lithium Metal Anodes with High Capacities
Protective coating: Li amalgam was studied for Li protection. The rational design of a Li anode with such a protective layer affords much improved cycling performance at practically high currents and capacities. Coupled with high‐loading cathodes, the protected hybrid anodes demonstrate significantly improved cell stability, indicating its reliability for practical development of Li metal batteries. Abstract Dendrite formation is a critical challenge for the applications of lithium (Li) metal...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:06
Mechanistic Divergence in the Hydrogenative Synthesis of Furans and Butenolides: Ruthenium Carbenes Formed by gem‐Hydrogenation or through Carbophilic Activation of Alkynes
One way or the other: Enynes bearing a tethered carbonyl group are transformed into furans upon catalytic hydrogenation using a ruthenium catalyst. Strikingly though, the reaction can follow two distinct pathways, each of which involves discrete metal carbene intermediates. They differ in that the hydrogenation and carbene formation are either synchronized (gem‐hydrogenation) or fully uncoupled. Abstract Enynes with a tethered carbonyl substituent are converted into substituted furan derivatives...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:04
Finely Controlled Circularly Polarized Luminescence of a Mechano‐Responsive Supramolecular Polymer
Chiral supramolecular polymerization is controlled, resulting from the tuning of mechanical stimulus. Weak, green emissions were converted into strong blue emissions by tuning the mechanical stimulus. The strong blue emissions were caused by an aggregation‐induced emission (AIE) effect during the formation of a supramolecular polymer. Abstract Finely controlled circularly polarized luminescence (CPL) supramolecular polymerization based on a tetraphenylethene core with four l‐ or d‐alanine branch...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:04
Base‐Stabilized [PO]+/[PO2]+ Cations
PO+ and PO2 + cations stabilized by cyclopropenylidene have been prepared by an atomically precise delivery of P+ and O atoms. The former species exhibits ambiphilic reactivity, while both species acts as electrophiles in reactions with fluoride. Abstract The salts [(BAC)2PO][BF4] (5) and [(BAC)2PO2][BF4] (4) (BAC=bis(diisopropylamino) cyclopropenylidene), consisting of the PO+ and PO2+ cations, respectively, coordinated to the singlet carbenes, have been prepared. Computational investigations...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:03

Interplay Between J‐ and H‐Type Coupling in Aggregates of π‐Conjugated Polymers: A Single‐Molecule Perspective
Coupling therapy: In organic electronics, J‐type coupling between monomers along the chain and H‐type coupling of chromophores between chains compete, which makes the two types of coupling hard to discern in the ensemble. A single‐molecule H‐type aggregate of fixed spacing and variable length of up to 10 nm is introduced, and HJ‐type aggregate formation is visualized intuitively in the scatter of single‐molecule spectra. Abstract Strong dipole–dipole coupling within and between π‐conjugated...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:03
Elucidating Ultrafast Molecular Permeation through Well‐Defined 2D Nanochannels of Lamellar Membranes
MXene Ti3C2T x nanosheets were functionalized by hydrophilic or hydrophobic groups to tune the size and wettability of 2D nanochannels for elucidating the molecular transport mechanism of lamellar membranes. Hydrophilic nanochannels induce ordered alignment of polar molecules, which contributes to their fast transport, and thus their permeance is much higher than that in hydrophobic nanochannels with disordered molecular configuration. Abstract Lamellar membranes with well‐defined...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:03
Wanbin Zhang
“My greatest achievement has been the synthesis of artemisinin. My biggest motivation was to make the ambitions of my youth become reality today …” Find out more about Wanbin Zhang in his Author Profile.
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:02
A Novel Metastable Pentavalent Plutonium Solid Phase on the Pathway from Aqueous Plutonium(VI) to PuO2 Nanoparticles
Solid proof: The formation of a novel pentavalent plutonium solid phase was observed on the pathway from aqueous PuVI to PuO2 nanoparticles by applying a high energy resolution fluorescence detection method at the Pu M4 and L3 edges and electronic structure calculations. Abstract Here we provide evidence that the formation of PuO2 nanoparticles from oxidized PuVI under alkaline conditions proceeds through the formation of an intermediate PuV solid phase, similar to NH4PuO2CO3, which is stable...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:01
Carboxy Group as a Remote and Selective Chelating Group for C−H Activation of Arenes
Coordination mode matters: The first example of carboxy group assisted, remote‐selective meta‐C(sp2)−H activation through a possible κ 2 coordination has been developed, thus suppressing the ortho‐C−H activation thorugh κ 1 coordination. Besides meta‐C−H olefination, direct meta‐arylation of hydrocinnamic acid derivatives with low‐cost aryl iodides has been achieved for the first time. These findings may motivate the exploration of novel selectivities and reactivities for carboxyl assisted C−H...
Angewandte Chemie International Edition
Wed Nov 06, 2019 16:00
Intermolecular Stereospecific Substitution of Underivatized Enantioenriched Secondary Alcohols by Organocatalysis
Mitsunobu revisited: The use of (2‐hydroxybenzyl)diphenylphosphine oxide as an efficient catalyst has recently enabled the development of a catalytic redox‐neutral Mitsunobu reaction. This reaction constitutes the first intermolecular stereospecific substitution of non‐allylic alcohols where only water is formed as a by‐product. Abstract The stereospecific substitution of non‐derivatized and non‐allylic enantioenriched alcohols with only water as a by‐product would enable the use of readily...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:59
Symmetric, Unsymmetrical, and Asymmetric [7]‐, [10]‐, and [13]Helicenes
All in a twirl: The gram‐scale synthesis of a series of azaoxa[7]‐, [10]‐, and [13]helicenes is described. The synthesis is based on iterative oxidative furan formation between 3,6‐dihydroxycarbazoles and/or 2‐naphthols. The optically pure [13]helicenes can be synthetically functionalized both at the termini (see picture: blue) and the periphery (red). Abstract Fully aromatic helicenes with more than one pitch‐length are illustrious synthetic targets with potential applications in advanced...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:58
Cyclic Alkenylsulfonyl Fluorides: Palladium‐Catalyzed Synthesis and Functionalization of Compact Multifunctional Reagents
A family of compact low‐molecular‐weight cyclic alkenylsulfonyl fluorides can be readily prepared from the corresponding alkenyl triflates using palladium catalysis. These densely functionalized reagents undergo a diverse range of derivatization reactions, including substitution at sulfur, conjugate addition, and N‐functionalization. Abstract A series of low‐molecular‐weight, compact, and multifunctional cyclic alkenylsulfonyl fluorides were efficiently prepared from the corresponding alkenyl...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:57
Supported Catalytically Active Supramolecular Hydrogels for Continuous Flow Chemistry
CASH flow: Catalytically active supramolecular hydrogels (CASHs) generated from a porous polymer foam by an enzyme‐assisted self‐assembly strategy are ideal catalytic phases for continuous flow. A hydrogel prepared from an original bis‐phosphorylated heptapeptide enables highly efficient ester hydrolysis and kinetic resolution. Abstract Inspired by biology, one current goal in supramolecular chemistry is to control the emergence of new functionalities arising from the self‐assembly of molecules....
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:56
Ultra‐Stable Plasmonic Colloidal Aggregates for Accurate and Reproducible Quantitative SE(R)RS in Protein‐Rich Biomedia
Emulsion‐templated self‐assembly produces reproducible and surface‐modification‐free, quasi‐spherical colloidal aggregates which remain stable for days. The high stability and strong plasmonic enhancement of these aggregates allow accurate and quantitative SE(R)RS detection of weakly adsorbing analytes in protein‐rich biomedia to be achieved. Abstract Au/Ag colloids aggregated with simple salts are amongst the most commonly used substrates in surface‐enhanced (resonance) Raman spectroscopy...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:55
Enantioselective Control of Both Helical and Axial Stereogenic Elements though an Organocatalytic Approach
A highly diastereo‐ and enantio‐selective method for the asymmetric synthesis of molecules containing helicene and stereogenic axes was developed based on organocatalysis. Various compounds bearing both helical and axial stereogenic elements were obtained in excellent enantioselectivities. Abstract A highly diastereo‐ and enantio‐selective method for the asymmetric synthesis of molecules containing helicenes and stereogenic axes was developed based on organocatalysis. Various compounds bearing...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:55
Rapid Activation of Platinum with Black Phosphorus for Efficient Hydrogen Evolution
Back in black: Surprisingly strong activation effects of black phosphorus (BP) on Pt catalysts and subsequent modulation the surface electronic structure of Pt result in greatly enhanced catalytic activity in the hydrogen evolution reaction (HER). Abstract Modulation of the electronic structure of metal catalysts is an effective approach to optimize the electrocatalytic activity. Herein, we show a surprisingly strong activation effect of black phosphorus (BP) on platinum (Pt) catalysts to give...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:55
KNCV Gold Medal for Ilja Voets / SBIC Early Career Award for Abhishek Dey / And also in the News
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:55
Anisotropically Electrochemical–Mechanical Evolution in Solid‐State Batteries and Interfacial Tailored Strategy
Solid as a rock: The unsatisfactory electrochemical performance in solid‐state batteries originates from internal strain‐induced contact loss, heterogeneous phase transformation, and the augmentation of metallic surface passivation layers. With in situ growth of solid sulfide electrolyte into 3D FeS2 microstructure, these issues can be significantly inhibited and superior electrochemical performance can be achieved. Abstract All‐solid‐state batteries have attracted attention owing to the potential...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:54
Solid‐State and Gas‐Phase Structures and Energetic Properties of the Dangerous Methyl and Fluoromethyl Nitrates
Six centuries after the discovery of the simplest nitric acid ester, methyl nitrate (H3CONO2), experimental solid‐state and gas‐phase structures as well as energetic properties are compared with those of the new monofluorine‐substituted analogue, fluoromethyl nitrate (FH2CONO2). Abstract An improved synthesis of the simplest nitric acid ester, methyl nitrate, and a new synthesis of fluoromethyl nitrate use the metathesis of the corresponding iodomethanes with silver nitrate. Both compounds...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:54
Inverting the Triiodide Formation Reaction by the Synergy between Strong Electrolyte Solvation and Cathode Adsorption for Lithium–Oxygen Batteries
I pod: The synergic effect of the strong binding of RuO2 to I2 and the strong solvation effect of DMSO to I2 is found to invert the direction of the well‐known reaction I−+I2⇌I3− to the left‐hand side. A Li–O2 battery with the Li/DMSO+LiI/RuO2 structure had enhanced stability compared to one with TEGDME. Abstract An exceptionally strong solvation effect of dimethyl sulfoxide (DMSO) on I2 is identified by the largest shift observed so far of the I2 Raman peak with respect to I2 vapor and by...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:53
Photo‐energy Conversion and Storage in an Aprotic Li‐O2 Battery
A photo‐promoted Li‐O2 battery has carbon nitride as a bifunctional photocatalyst to accelerate the formation and decomposition of Li2O2 in the discharge and charge process. It realizes photo‐energy conversion and storage in a Li‐O2 battery with a round‐trip efficiency of 95.3 % and an output energy density increase of 23.0 % compared to that in the dark. Abstract A photo‐involved Li‐O2 battery with carbon nitride (C3N4) is presented as a bifunctional photocatalyst to accelerate both oxygen...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:53
Thuricin Z: A Narrow‐Spectrum Sactibiotic that Targets the Cell Membrane
Genome mining led to the discovery of thuricin Z, a novel sactibiotic from Bacillus thuringiensis that exhibits narrow‐spectrum antibacterial activity against Bacillus cereus. Unusually, the gene cluster involves two radical SAM enzymes (ThzC and D) that are highly divergent but produce the same sactionine ring from the precursor peptide ThzA in vitro. Functional characterization suggests that thuricin Z acts by permeabilizing the bacterial cell membrane. Abstract Sactionine‐containing antibiotics...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:49
Expedient Synthesis of Core Disaccharide Building Blocks from Natural Polysaccharides for Heparan Sulfate Oligosaccharide Assembly
The four core disaccharides required for heparan sulfate (HS)/heparin oligosaccharide synthesis were efficiently generated from natural polysaccharides. Rapid access to these key building blocks will greatly facilitate the generation of comprehensive libraries of HS oligosaccharides for unlocking the sulfation code and understanding the roles of glycosaminoglycans in physiology and disease. Abstract The complex sulfation motifs of heparan sulfate glycosaminoglycans (HS GAGs) play critical roles...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:48
Asymmetric Synthesis of Oxa‐Bridged Oxazocines through a Catalytic RhII/ZnII Relay [4+3] Cycloaddition Reaction
A highly efficient asymmetric cascade reaction of β,γ‐unsaturated α‐ketoesters and diazoimides was realized by using a bimetallic rhodium(II)/chiral N,N′‐dioxide‐zinc(II) catalytic system. The corresponding oxa‐bridged oxazocine products bearing different substituents were obtained in moderate to excellent yields with excellent enantioselectivity under mild reaction conditions. Abstract Oxa‐bridged oxazocines bearing three chiral carbon centers were synthesized efficiently through a bimetallic...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:48

A Single Thermoresponsive Diblock Copolymer Can Form Spheres, Worms or Vesicles in Aqueous Solution
Every which way and loose: A single amphiphilic thermoresponsive diblock copolymer can reversibly form spheres, worms or vesicles in aqueous solution. Self‐consistent mean field theory indicates that this rich self‐assembly behavior arises from the temperature‐dependent degree of hydration of the structure‐directing hydrophobic poly(2‐hydroxypropyl methacrylate) block. Abstract It is well‐known that the self‐assembly of AB diblock copolymers in solution can produce various morphologies depending...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:47
Photochemical Strain‐Release‐Driven Cyclobutylation of C(sp3)‐Centered Radicals
High‐lying SOMO radicals, generated in situ under visible‐light photoredox conditions, undergo an efficient addition to highly strained bicyclo[1.1.0]butanes, providing a straightforward access to valuable alkylated cyclobutanes. Abstract A new photoredox‐catalyzed decarboxylative radical addition approach to functionalized cyclobutanes is described. The reaction involves an unprecedented formal Giese‐type addition of C(sp3)‐centered radicals to highly strained bicyclo[1.1.0]butanes. The mild...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:46
The Reactions of Carbon Monoxide with Silyl and Silenyl Lithium – Synthesis and Isolation of the First Stable Tetra‐Silyl Di‐Ketyl Biradical and 1‐Silaallenolate Lithium
Reaction of carbon monoxide with tBu2MeSiLi yields the first stable tetra‐silyl di‐ketyl biradical 2; with silenyl lithium 1 silaallenolate 3 is obtained.In 3 the bond in the inserted CO molecule is fully cleaved. Both 2 and 3 were characterized by X‐ray crystallography and biradical 2 also by EPR spectroscopy. Density functional theory (DFT) calculations suggest mechanisms for these reactions. Abstract Reactions of carbon monoxide (CO) with tBu2MeSiLi and (E)‐(tBu2MeSi)(tBuMe2Si)C=Si(SiMetBu2)Li⋅2 THF...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:46
Functionalization of Pentaphosphorus Cations by Complexation
Functionalization of P ligands: The first metal complexes of diorganopentaphosphorus cations [P5R2]+ (R=Cy, iPr) have been prepared from tetrachlorogallate salts [P5R2]GaCl4 and cyclopentadienyl cobalt and nickel complexes (CpAr=C5(C6H4‐4‐Et)5). The installation of additional chloro, cyano, and cyclohexyl groups on the pentaphosphorus scaffold illustrates a useful strategy to access highly functionalized polyphosphorus ligands. Abstract The chemistry of polyphosphorus cations has rapidly developed...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:46
Liquid Metastable Precursors of Ibuprofen as Aqueous Nucleation Intermediates
The nucleation mechanism of crystals of small organic molecules was studied for the crystallization of ibuprofen as a model system. Ibuprofen undergoes liquid–liquid phase separation prior to nucleation and forms a dense liquid phase that is identified as a precursor phase in the nucleation of ibuprofen. These results may provide insight for the development of new pharmaceutical formulations. Abstract The nucleation mechanism of crystals of small organic molecules, postulated based on computer...
Angewandte Chemie International Edition
Wed Nov 06, 2019 15:45
Oxodealkenylative cleavage of alkene C(sp3)–C(sp2) bonds: A practical method for introducing carbonyls into chiral pool materials
Herein we report a one‐pot protocol for the oxodealkenylative introduction of carbonyl functionalities into terpenes and terpene‐derived compounds. This transformation proceeds via Criegee ozonolysis of an alkene, reductive cleavage of the resulting α‐alkoxy hydroperoxide, trapping of the generated alkyl radical with TEMPO, and subsequent oxidative fragmentation with MMPP. Using readily available starting materials from chiral pool, a variety of carbonyl‐containing products have been accessed rapidly...
Angewandte Chemie International Edition
Wed Nov 06, 2019 14:52
Rare 3‐O‐sulfation of Heparan Sulfate Enhances Tau Interaction and Cellular Uptake
Prion‐like trans‐cellular spreading of tau in Alzheimer’s Disease (AD) is mediated by tau binding to cell surface heparan sulfate (HS). However, the structural determinants for tau‐HS interaction are not well understood. Microarray and SPR assays of structurally‐defined HS oligosaccharides show that a rare 3‐O‐sulfation(3‐O‐S) of HS significantly enhances tau binding. In Hs3st1‐/‐ (HS 3‐O‐sulfotransferase‐1 knockout) cells, reduced 3‐O‐S levels of HS diminished both cell surface binding and internalization...
Angewandte Chemie International Edition
Wed Nov 06, 2019 14:43
Physical Structure Selectivity of Universal Alkaline Periodate Oxidation on Lignocellulose for Facile Isolation of Cellulose Nanocrystals
In this work, we report for the first time the alkaline periodate oxidation on lignocelluloses for the selective isolation of cellulose nanocrystals (CNCs). With the high concentrations as potassium salt at pH 10, periodate ions predominantly exist as dimeric orthoperiodate ions (H2I2O104‐). With reduced oxidizing activity in alkaline solutions, dimeric orthoperiodate ions preferentially oxidized non‐ordered cellulose regions. The alkaline surroundings promoted the degradation of these oxidized cellulose...
Angewandte Chemie International Edition
Wed Nov 06, 2019 14:04
Effective utilization of NIR wavelengths for photo‐controlled polymerization – penetration through thick barriers and parallel solar syntheses
Abstract: This contribution details an efficient and controlled photopolymerization regulated by far‐red (λ = 680 nm) and NIR (λ = 780 and 850 nm) light in the presence of aluminum phthalocyanine and aluminum naphthalocyanine. Initiating radicals are generated by photosensitization of peroxides affording an effective strategy that provides controlled polymerizations of a variety of monomers with excellent living characteristics. Critically, the long wavelength irradiation provides penetration through...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:49
Tetraphenylethene‐Based Octacationic Cage
Cage‐type compounds offer molecule‐level confined spaces with different sizes, shapes, and functional groups for various molecule guests to achieve some specific behaviors/functions, such as ultrahigh affinity of host‐guest recognition, multi‐tunable photophysical property, and highly‐stereoselective/photo‐driven catalysis. Herein, we report the synthesis and characterization of three‐dimensional tetraphenylethene‐based octacationic cage with fluorescent property and host‐guest recognition via CH•••π,...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:48
Photoinduced multi‐effects to enhance uranium extraction from natural seawater by black phosphorus nanosheet
Rational design of adsorbent that targets the marine factors is highly possible to enhance the efficiency for uranium extraction from natural seawater. Herein, based on the photoinduced photothermal, photoelectric, and photocatalytic effects of black phosphorus (BP) nanosheets, a BP‐PAO fiber with enhanced uranium extraction capacity and high antibiofouling activity is fabricated by compositing BP nanosheets into polyacrylamidoxime (PAO). The photothermal effect increases the coordination interaction...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:44
Au(III) pi‐Allyl ComplexesA
Gold(III) pi‐complexes have been authenticated recently with alkenes, alkynes and arenes. The key importance of Pd(II) pi‐allyl complexes in organometallic chemistry (Tsuji‐Trost reaction) prompted us to explore gold(III) pi‐allyl complexes, which have remained so far elusive species. The (P,C)Au(III)(allyl) and (methallyl) complexes 3 and 3’ were readily prepared and isolated as thermally and air‐stable solids. Spectroscopic and crystallographic analyses combined with detailed DFT calculations support...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:37
Total Synthesis and Structural Revision of a Harziane Diterpenoid
The first total synthesis of nominal harziane diterpenoid 1 is disclosed, whose spectral characteristics did not match those of the reported natural product. Stereochemical analysis and subsequent synthesis of the epimeric tertiary alcohol led to reassignment of configuration of the natural product as shown for 2 . At the heart of the synthesis is an enyne cycloisomerization that sets a key quaternary stereocenter within a cyclobutane with high diastereocontrol. The route features strategies...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:25
Porphyrin/Quinoidal Bithiophene Based Macrocycles and Their Dications: Template‐free Synthesis and Global Aromaticity
We report the template‐free synthesis and characterization of a new type of porphyrin/quinoidal bithiophene based conjugated macrocycles. X‐ray crystallographic analysis on the dimer ( 2MC ) reveals a cyclophane‐like geometry with large dihedral angles between the porphyrin and the neighboring thiophene rings. Accordingly, NMR measurements and theoretical calculations confirm a localized aromatic character of the porphyrin/thiophene rings and quinoidal character of the bithiophene linkers. Restricted...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:21
Surface digging effect stabilized supported Ni catalyst for efficient methane oxidation
Durability of supported transition metal particles catalysts usually suffers from the sintering, which makes the increasement of nanoparticles (NPs) size and loss of reactive surface, resulting in catalysts deactivation. Herein, we discovered a surface digging effect of supported Ni NPs on an amorphous N‐doped carbon, during which the surface‐loaded Ni NPs would etch and sink into the underneath carbon support to prevent sintering. This process is driven by the strong coordination interaction between...
Angewandte Chemie International Edition
Wed Nov 06, 2019 13:16
Synergic Interplay Between Halogen Bond and Hydrogen Bond in the Activation of a Neutral Substrate in a Nanoconfined Space
The principle of the “amplified halogen bonding (XB) in a small space” is here exploited as a catalytic tool for the activation of a XB acceptor substrate in a nanoconfined environment. The inner cavity of the resorcinarene capsule has been equipped with a XB catalyst bearing an ammonium unit acting as a Trojan horse to drive the catalyst inside the capsule. In the presence of the XB catalyst 5, the capsule is able to catalyze a Michael reaction between N‐methylpyrrole and methyl vinyl ketone. In...
Angewandte Chemie International Edition
Wed Nov 06, 2019 12:16
Asymmetric Wacker‐Type oxyallenylation and Azaallenylation of Cyclic Alkenes
Palladium‐catalyzed three‐component carboetherification of cyclic alkenes proceeds to give exclusive trans ‐adducts in excellent enantioselectivity via a Wacker‐type pathway. The reaction is also applicable to other oxygen nucleophiles such as water, phenols and carboxylic acids, as well as some electron‐poor arylamines.
Angewandte Chemie International Edition
Wed Nov 06, 2019 11:39
Dual Illumination Enhances Transformation of an Engineered Green‐to‐Red Photoconvertible Fluorescent Protein
Photoconvertible fluorescent proteins have powered significant bioimaging and biomedical advances. However, molecular mechanisms for the light‐induced processes remain elusive due to challenges of tracking chromophore structural dynamics during photoconversion. We implemented time‐resolved electronic and stimulated Raman spectroscopies to reveal two hidden species of an engineered ancestral GFP‐like protein LEA, involving semi‐trapped protonated (GA’) and trapped deprotonated (GB’) chromophores en...
Angewandte Chemie International Edition
Wed Nov 06, 2019 11:06

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