bluuebunny/crossref_metadata_2025 huggingface dataset:
Brain dysfunction in COVID‐19 and CAR‐T therapy: cytokine storm‐associated encephalopathy
Authors: Pensato Umberto , Muccioli Lorenzo , Cani Ilaria , Janigro Damir , Zinzani Pier Luigi , Guarino Maria , Cortelli Pietro , Bisulli Francesca
Published: March 2021

Objective

Many neurological manifestations are associated with COVID‐19, including a distinct form of encephalopathy related to cytokine storm, the acute systemic inflammatory syndrome present in a subgroup of COVID‐19 patients. Cytokine storm is also associated with immune effector cell‐associated neurotoxicity syndrome (ICANS), a complication of chimeric antigen receptor T‐cell (CAR‐T) therapy, a highly effective treatment for refractory hematological malignancies. We investigated whether COVID‐19‐related encephalopathy, ICANS, and other encephalopathies associated with cytokine storm, share clinical and investigative findings.

Methods

Narrative literature review.

Results

Comparisons between COVID‐19‐related encephalopathy and ICANS revealed several overlapping features. Clinically, these included dysexecutive syndrome, language disturbances, akinetic mutism and delirium. EEG showed a prevalence of frontal abnormalities. Brain MRI was often unrevealing. CSF elevated cytokine levels have been reported. A direct correlation between cytokine storm intensity and severity of neurological manifestations has been shown for both conditions. Clinical recovery occurred spontaneously or following immunotherapies in most of the patients. Similar clinical and investigative features were also reported in other encephalopathies associated with cytokine storm, such as hemophagocytic lymphohistiocytosis, sepsis, and febrile infection‐associated encephalopathies.

Interpretation

COVID‐19‐related encephalopathy and ICANS are characterized by a predominant electro‐clinical frontal lobe dysfunction and share several features with other encephalopathies associated with cytokine storm, which may represent the common denominator of a clinical spectrum of neurological disorders. Therefore, we propose a unifying definition of cytokine storm‐associated encephalopathy (CySE), and its diagnostic criteria.
Advanced Applications of Atomic Layer Deposition in Perovskite‐Based Solar Cells
Authors: Zhao Wenzhuo , Duan Yu
Published: March 2021

Perovskite solar cells (PSCs) have shown remarkable photovoltaics progress with a record‐eminent power conversion efficiency (PCE) of 25.2%. Therefore, the PSCs are potential candidates to replace traditional crystalline silicon‐based solar cells. However, the PCE and stability of PSCs need to be improved for successful commercialization. Recently, the atomic layer deposition (ALD) technology is successfully applied to fabricate the encapsulation layer, which overcomes the long‐standing issues of perovskite‐based solar cells based on others’ pioneering work on ALD in PSCs several years ago. The organic–inorganic alternating encapsulation structure that the team researched has exhibited a water vapor transmittance rate of 1.3 × 10−5 g m−2 day−1, which is the lowest value among the reported thin‐film encapsulation layers of PSCs. Herein, the properties of ALD and how it is used in PSCs, such as device architecture, surface modification, passivation, and encapsulation, which result in higher PCEs and excellent stability, are discussed. In addition, the potential significance of applying ALD in the manufacture of tandem and flexible PSCs and the synthesis of high‐quality perovskite materials is also analyzed.
Temperature‐Responsive Photonic Devices Based on Cholesteric Liquid Crystals
Authors: Zhang Weixin , Froyen Arne A. F. , Schenning Albertus P. H. J. , Zhou Guofu , Debije Michael G. , de Haan Laurens T.
Published: March 2021

Cholesteric liquid crystals (CLCs) are a major class of photonic materials that display selective reflection properties arising from their helical ordering. The temperature response of CLCs, comprising dynamic reflection color changes upon variation of temperature, is exploited using material systems consisting of small mesogenic molecules, polymer‐dispersed liquid crystals (PDLCs), polymer‐stabilized liquid crystals (PSLCs), or liquid‐crystalline polymers. Taking advantage of the easy processability and flexibility of the molecular design, these temperature‐responsive CLCs are fabricated into different forms of photonic devices, including cells, coatings, free‐standing films, and 3D objects. Temperature‐responsive devices developed from CLCs are integrated for application in temperature sensors, energy‐saving smart windows, smart labels, actuators, and adding aesthetically pleasing features to common objects. Herein, the device capabilities of the different material systems of temperature‐responsive CLCs are summarized: small mesogenic molecules, PDLCs, PSLCs, and CLC polymers. For each system, examples of different device forms are presented, with their temperature responsiveness and the underlying mechanisms discussed. In addition, the potential of each material system for future device applications and product developments is envisioned.
High‐Resolution 960 × 540 and 1920 × 1080 UV Micro Light‐Emitting Diode Displays with the Application of Maskless Photolithography
Authors: Wu Meng-Chyi , Chen I-Ting
Published: March 2021

Herein, active matrix 370 nm ultraviolet (UV) micro light‐emitting diode (micro‐LED) displays with full high‐definition resolution of 960 × 540 and 1920 × 1080 and high pixel densities of almost 2000 and 3200 pixels per inch (PPI), respectively, are reported. A novel self‐aligned process is used to fabricate the 1920 × 1080 micro‐LED array with the inverted trapezoidal‐shape mesa, which is different from the conventional vertical mesa for the 960 × 540 micro‐LED array. In addition, the single pixels with the diameters of 8 and 5 μm on the 960 × 540 and 1920 × 1080 microarrays exhibit excellent characteristics, including the low forward voltages of 3.35 and 3.29 V at the currents of 17.4 and 4.4 μA, extremely low leakage currents of 19.5 and 9.4 pA at −10 V, and high light output powers of 150 and 71 μW at 1 mA, respectively. Through flip‐chip bonding technology, the 1920 × 1080 micro‐LED display has a higher light output power of 2.6 mW than the 960 × 540 micro‐LED display of 1.8 mW at the same driving current of 100 mA and voltage of 5 V. Both the UV micro‐LED displays demonstrate the delivery of graphic images and simple pattern‐programmable maskless photolithography on resist‐coated wafers.
Synthetic Approaches to Halogen Bonded Ternary Cocrystals
Authors: Jain Harsh , Sutradhar Dipankar , Roy Sourav , Desiraju Gautam R.
Published: March 2021

Higher cocrystal synthesis depends acutely on a knowledge of supramolecular synthons. We report three synthetic approaches towards ternary halogen bonded cocrystals that illustrate specificity and generality. Electrophilicity/nucleophilicity differences are needed among alternative sites of halogen bond formation. The two halogen bonds A⋅⋅⋅B and B⋅⋅⋅C in a halogen bonded ternary cocrystal ABC need to be of different strength. Interaction mimicry of hydrogen bonds by halogen bonds is a viable approach towards ternaries as illustrated with the pyrene structure. Finally, the crystal engineer should well be able to anticipate halogen bonds that are stronger than hydrogen bonds.
Copper‐Photocatalyzed Hydroboration of Alkynes and Alkenes
Authors: Zhong Mingbing , Gagné Yohann , Hope Taylor O. , Pannecoucke Xavier , Frenette Mathieu , Jubault Philippe , Poisson Thomas
Published: March 2021

The photocatalytic hydroboration of alkenes and alkynes is reported. The use of newly‐designed copper photocatalysts with B2Pin2 permits the formation a boryl radical, which is used for hydroboration of a large panel of alkenes and alkynes. The hydroborated products were isolated in high yields, with excellent diastereoselectivities and a high functional group tolerance under mild conditions. The hydroboration reactions were developed under continuous flow conditions to demonstrate their synthetic utility. The reaction mechanism was studied and suggested an oxidation reaction between an in situ formed borate and the Cu‐photocatalyst in its excited state for the boryl radical formation.
Discovery and Biosynthesis of a Structurally Dynamic Antibacterial Diterpenoid
Authors: Zhu Chenxi , Xu Baofu , Adpressa Donovon A. , Rudolf Jeffrey D. , Loesgen Sandra
Published: March 2021

A new bicyclic diterpenoid, benditerpenoic acid, was isolated from soil‐dwelling Streptomyces sp. (CL12‐4). We sequenced the bacterial genome, identified the responsible biosynthetic gene cluster, verified the function of the terpene synthase, and heterologously produced the core diterpene. Comparative bioinformatics indicated this Streptomyces strain is phylogenetically unique and possesses nine terpene synthases. The absolute configurations of the new trans‐fused bicyclo[8.4.0]tetradecanes were achieved by extensive spectroscopic analyses, including Mosher's analysis, J‐based coupling analysis, and computations based on sparse NMR‐derived experimental restraints. Interestingly, benditerpenoic acid exists in two distinct ring‐flipped bicyclic conformations with a rotational barrier of ≈16 kcal mol−1 in solution. The diterpenes exhibit moderate antibacterial activity against Gram‐positive bacteria including methicillin and multi‐drug resistant Staphylococcus aureus. This is a rare example of an eunicellane‐type diterpenoid from bacteria and the first identification of a diterpene synthase and biosynthetic gene cluster responsible for the construction of the eunicellane scaffold.
Craniofacial developmental concepts in dynamic osteotomies and the Nautilus technique: A procedure created in Brazil for the treatment of craniosynostosis
Authors: dos Santos Silva Alessandra , Cardim Vera Lúcia Nocchi
Published: March 2021

Craniofacial development is the major focus of attention in surgical treatments for craniosynostosis. Growth rate, size, shape, and proportion of soft tissue and bone structures of the skull and face are determinant factors in the establishment of the vital functions of swallowing and breathing, as well as in the aesthetic balance of facial features, so important for the patient's psychological identity. This manuscript revisits the concept of craniosynostosis and reviews the major biological and anatomical factors that come into play in the developmental process of craniofacial structures, especially during infancy and early childhood. It also describes the Nautilus surgical technique, a corrective procedure created and implemented in Brazil in 2011—how it was created and how it has evolved: as we look back into the past 10 years, we shed light onto what was learned, on our contributions to improve treatments over time, and on how much we still have to discover in this fascinating area.
Development and validation of an LC–MS/MS method for relevant drugs in epilepsy patients using dried blood spots
Authors: Möller Ines , Held Kathrin , Klimpel Dennis , Nadulski Thomas , Dufaux Bertin
Published: March 2021

Epilepsy is one of the most common diseases of the central nervous system globally. To ensure the correct dosage of antiepileptic treatment, it is helpful to check the blood levels of the administered substances regularly. The analysis of the capillary dried blood samples provides a promising and less‐invasive alternative to venous blood collection. Therefore, the aim of the present study was to develop an LC–MS method for the quantification of 22 commonly used drugs in patients with an epileptic syndrome and 5 drug metabolites in one dried blood spot (DBS). The calibration ranges were selected in such a way that the therapeutic reference ranges in serum for the respective substances were completely covered. The analytical validation was successfully performed according to relevant guidelines with a consideration of requirements for DBS analysis. Proof of concept of the developed method was obtained by the analysis of DBSs from 282 authentic leftover ethylenediaminetetraacetic acid blood samples, which were compared with the corresponding serum concentrations. Altogether, the results show a dependency on the blood/plasma (b/p) ratios of the respective analytes so that for drugs with b/p ratios close to one, for example, lacosamide, levetiracetam, brivaracetam, and sertraline, a good accordance was observed.
HPLC/HR‐MS‐Based Metabolite Profiling and Chemometrics: A Powerful Approach to Identify Bioactive Compounds from Abarema cochliacarpos
Authors: de S. Farias Caroline , Dias de Cerqueira Martins , Colepicolo Pio , Zambotti‐Villela Leonardo , Fernandez Luzimar G. , Ribeiro Paulo R.
Published: March 2021

Despite its importance as a medicinal plant, there is a lack of studies that assessed the chemical composition of A. cochliacarpos extracts. Herein, we used a metabolite profiling approach and chemometrics as a powerful strategy to correlate the chemical composition with the antioxidant activity of A. cochliacarpos extracts. Extracts obtained with ethyl acetate showed greater antioxidant activity and higher total phenolic content than extracts obtained with hexane. The chemical composition was assessed by HPLC/HR‐MS and it encompassed fatty alcohols, terpenoids, phenolic derivatives, lipids, carotenoid‐like compounds, alkaloids, flavonoids, polyketides, and glycerophospholipids. Chemometrics successfully differentiated not only the chemical composition of extracts in response to the nature of the extraction solvent and the botanical part used during extraction but also it allowed us to associate the chemical composition with the antioxidant activity of the extracts, which might be particularly helpful for drug discovery and development programs.
A Mutation‐Based Method for Pinpointing a DNA N6‐Methyladenine Methyltransferase Modification Site at Single Base Resolution
Authors: Cheng Mohan , Shu Xiao , Cao Jie , Gao Minsong , Xiang Siying , Wang Fengqin , Wang Yizhen , Liu Jianzhao
Published: March 2021

DNA N6‐methyladenine (6mA) has recently received notable attention due to an increased finding of its functional roles in higher eukaryotes. Here we report an enzyme‐assisted chemical labeling method to pinpoint the DNA 6mA methyltransferase (MTase) substrate modification site at single base resolution. A designed allyl‐substituted MTase cofactor was applied in the catalytic transfer reaction, and the allyl group was installed to the N6‐position of adenine within a specific DNA sequence to form N6‐allyladenine (6aA). The iodination of 6aA allyl group induced the formation of 1, N6‐cyclized adenine which caused mutations during DNA replication by a polymerase. Thus the modification site could be precisely detected by a mutation signal. We synthesized 6aA deoxynucleoside and deoxynucleotide model compounds and a 6aA‐containing DNA probe, and screened nine DNA polymerases to define an optimal system capable of detecting the substrate modification site of a DNA 6mA MTase at single‐base resolution.
Association of the age shock index with coronary plaque characteristics in ST‐segment elevation myocardial infarction: A 3‐vessel optical coherence tomography study
Authors: Zhao Linlin , Du Zhuo , Wu Tianyu , Cao Muhua , Wang Yini , Zhao Jiawei , Dong Hui , Wang Chao , Jia Haibo , Yu Bo
Published: March 2021

Objectives

We investigated whether the age shock index (SI) was associated with coronary plaque characteristics in patients with ST‐segment elevation myocardial infarction (STEMI) using optical coherence tomography (OCT).

Background

The age SI is a simple clinical parameter that effectively predicts poor clinical outcomes among patients with STEMI.

Methods

This retrospective study evaluated 408 STEMI patients who underwent 3‐vessel OCT during emergency percutaneous coronary interventions at a single center between January 2017 and October 2018. Patients were divided into groups with low or high age SI values (<41 vs. ≥41). Plaque characteristics were compared between the two groups for both culprit lesions (n = 408) and non‐culprit lesions (n = 1,077).

Results

In culprit lesions, patients with a high age SI (≥41) were more likely to have plaque rupture (61.0% vs. 56.8%, p = .002) and thinner fibrous caps (fibrous cap thickness [FCT]: 40.0 [33.0–53.0] μm vs. 46.0 [36.0–63.8] μm, p = .021). In non‐culprit lesions, patients with a high age SI were more likely to have high‐risk plaques (29.9% vs. 17.8%, p = .018; simultaneous presence of a minimal lumen area of <3.5 mm2, maximum lipid arc of >180°, FCT of <75 μm, and macrophage accumulation). Plaque‐based analyses revealed that patients with a high age SI had larger lipid cores and lesser FCT.

Conclusions

Patients with STEMI and a high age SI had increased risks of culprit plaque rupture and high‐risk non‐culprit plaques, and vulnerable plaque features at the culprit and non‐culprit lesions. Therefore, a high age SI in patients with STEMI may indicate greater pancoronary vulnerability.
Statin‐associated necrotizing autoimmune myopathy with concurrent myasthenia gravis
Authors: Frasson Emma , Simonetto Marco , Bertolasi Laura , Caneve Giorgio , Vilotti Cristina , Ruzza Giampietro , Perelli Anna , Piccinno Maria Grazia , Monaco Salvatore
Published: March 2021

Statin treatment has been associated with necrotizing autoimmune myopathy and has been linked to myasthenia gravis. We present an unprecedented clinical challenge with both disorders occurring in a patient treated with statins few months earlier.
Management of perioperative acute massive pulmonary embolism: A case series
Authors: Kim Ji‐Yoon , Lee Young‐Seok , Park Hyun Oh , Shin Il Woo
Published: March 2021

The management of acute massive pulmonary embolism during the perioperative period is challenging. Accurate diagnosis using echocardiography and application of rapid extracorporeal membrane oxygenation can improve patients' outcomes.
One‐Pot Palladium‐Catalyzed Carbonylative Sonogashira Coupling using Carbon Dioxide as Carbonyl Source
Authors: Xiong Wenfang , Wu Bowen , Zhu Baiyao , Tan Xiaobin , Wang Lu , Wu Wanqing , Qi Chaorong , Jiang Huanfeng
Published: March 2021

Carbonylation coupling reaction has emerged as a powerful and versatile strategy for the construction of carbonyl‐containing compounds in modern synthetic chemistry over the past years. Carbon dioxide, a renewable one carbon molecule, has become one of the most attractive and promising alternative carbonyl sources due to its highly abundance, nontoxicity and stability in comparison with CO in recent years. However, in most cases, a two‐chamber technique was generally necessary to allow the CO‐producing and CO‐consuming processes to perform successfully because of the complexities and incompatibility of reaction conditions, when carbon dioxide was utilized as carbonyl source. Herein, a practical one‐pot protocol using carbon dioxide as the carbonyl source for the palladium‐catalyzed carbonylative Sonogashira coupling has been established, providing an expedient and practical route to a wide range of functionalized alkynones and indoxyls under mild reaction conditions. By finding a suitable catalytic system, the method allowed the CO‐generating and CO‐consuming processes to proceed in one pot, wherein carbon monoxide was generated in situ from the reduction of carbon dioxide in the absence of any fluoride reagents. Simple and safe operation, readily available substrates, good functional group tolerance and mild reaction conditions are the features of the method.
Modeling of Fixed‐Bed Rapid Temperature Swing Adsorber for Butanol Dehydration
Authors: Mansouri Mohsen , Azizi Hamid Reza , Setareshenas Naimeh
Published: March 2021

A fixed‐bed system of rapid temperature swing adsorption (RTSA), which uses a solid absorbent for dehydration of butanol, was studied. The packed bed was simulated using proper partial and algebraic equations which were solved by the central difference method in MATLAB software. The equilibrium relationship and fixed‐bed breakthrough curves were determined experimentally. The value of unknown parameters such as equilibrium constants, liquid film mass transfer coefficient, intraparticle diffusion coefficient, and axial diffusivity were estimated by appropriate equations. The model fitted well to experimental breakthrough data. The results proved that it would be possible to operate a complete RSTA cycle in just a few hours to allow a large quantity of organic solvent dehydrated with reasonable concentration.
Excited State Properties of Lanthanide(III) Complexes with a Nonadentate Bispidine Ligand
Authors: Abad‐Galán Laura , Cieslik Patrick , Comba Peter , Gast Michael , Maury Olivier , Neupert Lucca , Roux Amandine , Wadepohl Hubert
Published: March 2021

EuIII, TbIII, GdIII and YbIII complexes of the nonadentate bispidine derivative L2 (bispidine=3,7‐diazabicyclo[3.3.1]nonane) were successfully synthesized and their emission properties studied. The X‐ray crystallography reveals full encapsulation by the nonadentate ligand L2 that enforces to all LnIII cations a common highly symmetrical capped square antiprismatic (CSAPR) coordination geometry (pseudo C4v symmetry). The well‐resolved identical emission spectra in solid state and in solution confirm equal structures in both media. As therefore expected, this results in long‐lived excited states and high emission quantum yields ([EuIIIL2]+, H2O, 298 K, τ=1.51 ms, ϕ=0.35; [TbIIIL2]+, H2O, 298 K, τ=1.95 ms, ϕ=0.68). Together with the very high kinetic and thermodynamic stabilities, these complexes are a possible basis for interesting biological probes.
Imide Condensation as a Strategy for the Synthesis of Core‐Diversified G‐Quadruplex Ligands with Anticancer and Antiparasitic Activity**
Authors: Street Steven T. G. , Peñalver Pablo , O'Hagan Michael P. , Hollingworth Gregory J. , Morales Juan C. , Galan M. Carmen
Published: March 2021

A facile imide coupling strategy for the one‐step preparation of G‐quadruplex ligands with varied core chemistries is described. The G‐quadruplex stabilization of a library of nine compounds was examined using FRET melting experiments, and CD, UV‐Vis, fluorescence and NMR titrations, identifying several compounds that were capable of stabilizing G‐quadruplex DNA with interesting selectivity profiles. The best G4 ligand was identified as compound 3, which was based on a perylene scaffold and exhibited 40‐fold selectivity for a telomeric G‐quadruplex over duplex DNA. Surprisingly, a tetra‐substituted flexible core, compound 11, also exhibited selective stabilization of G4 DNA over duplex DNA. The anticancer and antiparasitic activity of the library was also examined, with the lead compound 3 exhibiting nanomolar inhibition of Trypanosoma brucei with 78‐fold selectivity over MRC5 cells. The cellular localization of this compound was also studied via fluorescence microscopy. We found that uptake was time dependant, with localization outside the nucleus and kinetoplast that could be due to strong fluorescence quenching in the presence of small amounts of DNA.
In Situ Nitrogen Retention of Carbon Anode for Enhancing the Electrochemical Performance for Sodium‐Ion Battery
Authors: Shi Hui , Wang Ziheng , Ouyang Qin , Hao Jianwei , Huang Xianbo
Published: March 2021

Retaining nitrogen for polyacrylonitrile (PAN) based carbon anode is a cost‐effective way to make full use of the advantages of PAN for sodium‐ion batteries (SIBs). Here, a simple strategy has been successfully adopted to retain N atoms in situ and increase production yield of a novel composite PAZ by mixing 3 wt % of zinc borate (ZB) with poly (acrylonitrile‐co‐itaconic acid) (PANIA). Among the prepared carbonised fibre (CF) samples, PAZ‐CF‐700 maintains the highest N content, retaining 90 % of the original N from PANIA. It represents the highest capacity storage contribution (80.55 %) and the lowest impedance Rct (117 Ω). Consequently, the specific capacity increases from 60 mAh g−1 of PANIA‐CF‐700 to 190 mAh g−1 of PAZ‐CF‐700 at a current density of 100 mA g−1. At the same time, PAZ‐CF‐700 exhibits a good rate performance and excellent long‐term cycling stability with a specific capacity of 94 mAh g−1 after 4000 cycles at 1.6 A g−1.
Na2FePO4F/Biocarbon Nanocomposite Hollow Microspheres Derived from Biological Cell Template as High‐Performance Cathode Material for Sodium‐Ion Batteries
Authors: Li Haiming , Wang Tailin , Wang Xue , Li Guangda , Shen Jianxing , Chai Jinling
Published: March 2021

We have successfully synthesized Na2FePO4F/biocarbon nanocomposite hollow microspheres from FeIIIprecursor as cathodes for sodium‐ion batteries through self‐assembly of yeast cell biotemplate and sol‐gel technology. The carbon coating on the nanoparticle surface with a mesoporous structure enhances electron diffusion into Na2FePO4F crystal particles. The improved electrochemical performance of Na2FePO4F/biocarbon nanocomposites is attributed to the larger electrode−electrolyte contact area and more active sites for Na+on the surface of hollow microspheres compared with those of Na2FePO4F/C. The Na2FePO4F/biocarbon nanocomposite exhibits a high initial discharge capacity of 114.3 mAh g−1at 0.1 C, long‐cycle stability with a capacity retention of 74.3 % after 500 cycles at 5 C, and excellent rate capability (70.2 mAh g−1at 5 C) compared with Na2FePO4F/C. This novel nanocomposite hollow microsphere structure is suitable for improving the property of other cathode materials for high‐power batteries.
Effect of Manganese Valence on Specific Capacitance in Supercapacitors of Manganese Oxide Microspheres
Authors: Chen Xing , Li Lei , Wang Xiaoli , Xie Kun , Wang Yuqiao
Published: March 2021

Manganese oxides have attracted great interest in electrochemical energy storage due to high theoretical specific capacitance and abundant valence states. The multiple valence states in the redox reactions are beneficial for enhancing the electrochemical properties. Herein, three manganese microspheres were prepared by a one‐pot hydrothermal method and subsequent calcination at different temperatures using carbon spheres as templates. The trivalent manganese of Mn2O3 exhibited multiple redox transitions of Mn3+/Mn2+ and Mn4+/Mn3+ during the intercalation/deintercalation of electrolyte ions. The possible redox reactions of Mn2O3 were proposed based on the cyclic voltammetry and differential pulse voltammogram results. Mn2O3 microsphere integrated the advantages of multiple redox couples and unique structure, demonstrating a high specific capacitance and long cycling stability. The symmetric Mn2O3//Mn2O3 device yielded a maximum energy density of 29.3 Wh kg−1 at 250 W kg−1.
Spectroscopic Studies of Synthetic Methylaluminoxane: Structure of Methylaluminoxane Activators
Authors: Joshi Anuj , Collins Scott , Linnolahti Mikko , Zijlstra Harmen S. , Liles Elena , McIndoe J. Scott
Published: March 2021

Hydrolysis of trimethylaluminum (Me3Al) in polar solvents can be monitored by electrospray ionization mass spectrometry (ESI‐MS) using the donor additive octamethyltrisiloxane [(Me3SiO)2SiMe2, OMTS]. Using hydrated salts, hydrolytic methylaluminoxane (h‐MAO) features different anion distributions, depending on the conditions of synthesis, and different activator contents as measured by NMR spectroscopy. Non‐hydrolytic MAO was prepared using trimethylboroxine. The properties of this material, which contains incorporated boron, differ significantly from h‐MAO. In the case of MAO prepared by direct hydrolysis, oligomeric anions are observed to rapidly form, and then more slowly evolve into a mixture dominated by an anion with m/z 1375 with formula [(MeAlO)16(Me3Al)6Me]−. Theoretical calculations predict that sheet structures with composition (MeAlO)n(Me3Al)m are favoured over other motifs for MAO in the size range suggested by the ESI‐MS experiments. A possible precursor to the m/z 1375 anion is a local minimum based on the free energy released upon hydrolysis of Me3Al.
Dual‐Functional Mesoporous Copper(II) Metal‐Organic Frameworks for the Remediation of Organic Dyes
Authors: Au Vonika Ka‐Man , Kwan Shuk Ying , Lai Mio Nga , Low Kam‐Hung
Published: March 2021

By using tritopic and ditopic organic linkers derived from the same 2,4,6‐triphenylpyridine core, copper(II) metal‐organic frameworks with different three‐dimensional structures have been successfully synthesized under ambient conditions. The crystalline framework, PTBMOF ([Cu3(PTB)2(H2O)3]n, where H3PTB=4,4′,4′′‐(pyridine‐2,4,6‐triyl)tribenzoic acid, was observed to be mesoporous in nature and exhibited dual functionality in the removal of organic dyes. While cationic dyes such as methylene blue and malachite green, which are of different sizes, were adsorbed by PTBMOF; anionic dyes such as tartrazine could be effectively degraded in a photo‐Fenton‐like reaction catalyzed by the MOFs under irradiation with visible light.
The Mechanism of Cleavage of RNA Phosphodiesters by a Gold Nanoparticle Nanozyme
Authors: Czescik Joanna , Mancin Fabrizio , Strömberg Roger , Scrimin Paolo
Published: March 2021

The cleavage of uridine 3’‐phosphodiesters bearing alcohols with pKa ranging from 7.14 to 14.5 catalyzed by AuNPs functionalized with 1,4,7‐triazacyclononane‐Zn(II) complexes has been studied to unravel the source of catalysis by these nanosystems (nanozymes). The results have been compared with those obtained with two Zn(II) dinuclear catalysts for which the mechanism is fairly understood. Binding to the Zn(II) ions by the substrate and the uracil of uridine was observed. The latter leads to inhibition of the process and formation of less productive binding complexes than in the absence of the nucleobase. The nanozyme operates with these substrates mostly via a nucleophilic mechanism with little stabilization of the pentacoordinated phosphorane and moderate assistance in leaving group departure. This is attributed to a decrease of binding strength of the substrate to the catalytic site in reaching the transition state due to an unfavorable binding mode with the uracil. The nanozyme favors substrates with better leaving groups than the less acidic ones.
Anthrathiadiazole Derivatives: Synthesis, Physical Properties and Two‐photon Absorption
Authors: Fan Mingxuan , Chen Guangsheng , Xiang Yu , Li Junbo , Yu Xianglin , Zhang Wenying , Long Xueting , Xu Liang , Wu Jinjun , Xu Ze , Zhang Qichun
Published: March 2021

Anthrathiadiazole is a key synthon for the construction of large azaacenes, however, the attachment of different substituents onto the skeleton of anthrathiadiazole is difficult but highly desirable because it could be easy to enrich the structures of azaacenes. Here, it is demonstrated that anthrathiadiazole derivatives with −Br, −CN, and −OCH3 groups could be easily constructed through a simple [4+2] cycloaddition reaction between a,a,a’,a’‐tetrabromo‐o‐xylenes derivatives and benzo[c][1,2,5]thiadiazole‐4,7‐dione. The structures of the as‐prepared compounds with different substituents were carefully characterized. Moreover, the basic physical properties of the as‐prepared anthrathiadiazole derivatives were fully investigated, where the cyano‐substituted derivative (BTH‐CN) has the highest stability and the methoxy‐substituted derivative (BTH‐OCH3) is easy to be oxidized. Moreover, the two‐photon absorption (TPA) characteristics of different anthrathiadiazoles are also studied by using the femtosecond Z‐scan technique. The results show that the fused anthrathiadiazole skeletons possess large TPA cross‐section values δ2 in the range of 3000–5000 GM, where the nature, position and strength of the substituted groups have strong effect on these values.
Ultraviolet‐Cured Semi‐Interpenetrating Network Polymer Electrolytes for High‐Performance Quasi‐Solid‐State Lithium Metal Batteries
Authors: Xie Hui‐xin , Fu Qian‐gang , Li Zhuo , Chen Shuang , Wu Jia‐min , Wei Lu , Guo Xin
Published: March 2021

Solid polymer electrolytes with relatively low ionic conductivity at room temperature and poor mechanical strength greatly restrict their practical applications. Herein, we design semi‐interpenetrating network polymer (SNP) electrolyte composed of an ultraviolet‐crosslinked polymer network (ethoxylated trimethylolpropane triacrylate), linear polymer chains (polyvinylidene fluoride‐co‐hexafluoropropylene) and lithium salt solution to satisfy the demand of high ionic conductivity, good mechanical flexibility, and electrochemical stability for lithium metal batteries. The semi‐interpenetrating network has a pivotal effect in improving chain relaxation, facilitating the local segmental motion of polymer chains and reducing the polymer crystallinity. Thanks to these advantages, the SNP electrolyte shows a high ionic conductivity (1.12 mS cm−1 at 30 °C), wide electrochemical stability window (4.6 V vs. Li+/Li), good bendability and shape versatility. The promoted ion transport combined with suppressed impedance growth during cycling contribute to good cell performance. The assembled quasi‐solid‐state lithium metal batteries (LiFePO4/SNP/Li) exhibit good cycling stability and rate capability at room temperature.
Benzenedisulfonic Acid as an ALD/MLD Building Block for Crystalline Metal‐Organic Thin Films**
Authors: Heiska Juho , Sorsa Olli , Kallio Tanja , Karppinen Maarit
Published: March 2021

Two new atomic/molecular layer deposition processes for depositing crystalline metal‐organic thin films, built from 1,4‐benzenedisulfonate (BDS) as the organic linker and Cu or Li as the metal node, are reported. The processes yield in‐situ crystalline but hydrated Cu‐BDS and Li‐BDS films; in the former case, the crystal structure is of a previously known metal‐organic‐framework‐like structure, while in the latter case not known from previous studies. Both hydrated materials can be readily dried to obtain the crystalline unhydrated phases. The stability and the ionic conductivity of the unhydrated Li‐BDS films were characterized to assess their applicability as a thin film solid polymer Li‐ion conductor.
d/f‐Polypnictides Derived by Non‐Classical Ln2+ Compounds: Synthesis, Small Molecule Activation and Optical Properties
Authors: Reinfandt Niklas , Michenfelder Nadine , Schoo Christoph , Yadav Ravi , Reichl Stephan , Konchenko Sergey N. , Unterreiner Andreas N. , Scheer Manfred , Roesky Peter W.
Published: March 2021

Reduction chemistry induced by divalent lanthanides has been primarily focused on samarium so far. In light of the rich physical properties of the lanthanides, this limitation to one element is a drawback. Since molecular divalent compounds of almost all lanthanides have been available for some time, we used one known and two new non‐classical reducing agents of the early lanthanides to establish a sophisticated reduction chemistry. As a result, six new d/f‐polyphosphides or d/f‐polyarsenides, [K(18‐crown‐6)] [Cp′′2Ln(E5)FeCp*] (Ln=La, Ce, Nd; E=P, As) were obtained. Their reactivity was studied by activation of P4, resulting in a selective expansion of the P5 rings. The obtained compounds [K(18‐crown‐6)] [Cp′′2Ln(P7)FeCp*] (Ln=La, Nd) are the first examples of an activation of P4 by a f‐element‐polypnictide complex. Additionally, the first systematic femtosecond (fs)‐spectroscopy investigations of d/f‐polypnictides are presented to showcase the advantages of having access to a broader series of lanthanide compounds.
Intersystem Crossing and Electron Spin Selectivity in Anthracene‐Naphthalimide Compact Electron Donor‐Acceptor Dyads Showing Different Geometry and Electronic Coupling Magnitudes
Authors: Chen Kepeng , Kurganskii Ivan V. , Zhang Xue , Elmali Ayhan , Zhao Jianzhang , Karatay Ahmet , Fedin Matvey V.
Published: March 2021

Anthracene‐naphthalimide (An‐NI) compact electron donor‐acceptor dyads were prepared, in which the orientation and distance between the two subunits were varied by direct connection or with intervening phenyl linker. Efficient intersystem crossing (ISC) and long triplet state lifetime (ΦΔ=92 %, τT=438 μs) were observed for the directly connected dyads showing a perpendicular geometry (81°). This efficient spin‐orbit charge transfer ISC (SOCT‐ISC) takes 376 fs, inhibits the direct charge recombination (CR) to ground state (1CT→S0, takes 3.04 ns). Interestingly, efficient SOCT‐ISC for dyads with intervening phenyl linker (ΦΔ=40 % in DCM) was also observed, although the electron donor and acceptor adopt almost coplanar geometry (dihedral angle: 15°). Time‐resolved electron paramagnetic resonance (TREPR) spectroscopy shows that the electron spin polarization of the triplet state, i. e. the electron spin selectivity of ISC, is highly dependent on the dihedral angle and the linker. For the dyads showing weaker coupling between the donor and acceptors, the charge separation and the intramolecular triplet energy transfer are inhibited at 80 K (frozen solution), because both the 3An and 3NI states were observed and the ESP are same as compared to the native anthracene and naphthalimide, which unravel their origin. The dyads were used as triplet photosensitizers for triplet−triplet annihilation upconversion (TTA UC). High UC quantum yield (ΦUC=12.9 %) as well as a large anti‐Stokes shift (0.72 eV) was attained by excitation into the CT absorption band.
Cationic Aluminium Complexes as Catalysts for Imine Hydrogenation
Authors: Friedrich Alexander , Eyselein Jonathan , Elsen Holger , Langer Jens , Pahl Jürgen , Wiesinger Michael , Harder Sjoerd
Published: March 2021

Strongly Lewis acidic cationic aluminium complexes, stabilized by β–diketiminate (BDI) ligands and free of Lewis bases, have been prepared as their B(C6F5)4− salts and were investigated for catalytic activity in imine hydrogenation. The backbone (R1) and N (R2) substituents on the R1,R2BDI ligand (R1,R2BDI=HC[C(R1)N(R2)]2) influence sterics and Lewis acidity. Ligand bulk increases along the row Me,DIPPBDI<Me,DIPePBDI≈tBu,DIPPBDI<tBu,DIPePBDI; DIPP=2,6‐C(H)Me2‐phenyl, DIPeP=2,6‐C(H)Et2‐phenyl. The Gutmann‐Beckett test showed acceptor numbers of: (tBu,DIPPBDI)AlMe+ 85.6, (tBu,DIPePBDI)AlMe+ 85.9, (Me,DIPPBDI)AlMe+ 89.7, (Me,DIPePBDI)AlMe+ 90.8, (Me,DIPPBDI)AlH+ 95.3. Steric and electronic factors need to be balanced for catalytic activity in imine hydrogenation. Open, highly Lewis acidic, cations strongly coordinate imine rendering it inactive as a Frustrated Lewis Pair (FLP). The bulkiest cations do not coordinate imine but its combination is also not an active catalyst. The cation (tBu,DIPPBDI)AlMe+ shows the best catalytic activity for various imines and is also an active catalyst for the Tishchenko reaction of benzaldehyde to benzylbenzoate. DFT calculations on the mechanism of imine hydrogenation catalysed by cationic Al complexes reveal two interconnected catalytic cycles operating in concert. Hydrogen is activated either by FLP reactivity of an Al⋅⋅⋅imine couple or, after formation of significant quantities of amine, by reaction with an Al⋅⋅⋅amine couple. The latter autocatalytic Al⋅⋅⋅amine cycle is energetically favoured.
Quadruple Photoresponsive Functionality in a Crystalline Hybrid Material: Photochromism, Photomodulated Fluorescence, Magnetism and Nonlinear Optical Properties
Authors: Han Song‐De , Liu Ai‐u , Wei Qi , Hu Ji‐Xiang , Pan Jie , Wang Guo‐Ming
Published: March 2021

As promising photoresponsive materials and potential smart materials, hybrid photochromic materials (HPMs), especially for crystalline HPMs (CHPMs), have been broadly explored for their potential in inheriting the merits of each constituents, and intriguing photomodulated functionality. Hitherto, the photoresponsive functionality in explored CHPMs mainly concentrate on dyad combination. By contrast, triple or quadruple photoresponsive properties are very rare because of the limited compatibility of multiple photoresponsive functionality in a single system. In this work, the electron‐transfer (ET) and crystal engineering strategies were utilized to predesign CHPMs with multiple photoresponsive properties via the collaboration of paramagnetic metal ion (Dy3+), electron‐donor (ED) ligand (benzene‐1,2,3‐tricarboxylic acid, H3BTA) and electron‐acceptor (EA) ligand (1,10‐phenanthroline, phen). The resulting complex [Dy(BTA)(phen)2]⋅2H2O (1) shows hybrid chain with the intrachain Dy3+ ions bridged and chelated by tricarboxylate and phen ligands, respectively. After photostimuli, the ET between tricarboxylate and phen results in photogenerated radicals and the resultant quadruple photoresponsive properties. Considering the abundant resources of paramagnetic metal ions, ED‐ and EA‐ligands, this work provides a general method to construct CHPMs with multiple photoresponsive performances via the collaboration of each unit under the guidance of ET and crystal engineering strategies.
Intrinsic Molybdenum‐Based POMOFs with Impressive Gas Adsorptions and Photochromism
Authors: Deng Lan , Dong Xin , Zhou Zhao‐Hui
Published: March 2021

Novel molybdenum(VI/V) POM‐based self‐constructed frameworks [MoVI12O24(μ2‐O)12(trz)6(H2O)6] ⋅ 6Hma ⋅ 18H2O (1, Htrz=1H‐1,2,3‐triazole, ma=methylamine), [MoVI7O14(μ2‐O)8(trz)5(H2O)] ⋅ 7Hma ⋅ 5H2O (2), Na3[MoV6O6(μ2‐O)9(Htrz)3(trz)3] ⋅ 7.5H2O (3) and [MoV8O8(μ2‐O)12(Htrz)8] ⋅ 30H2O (4) have been covalently decorated with tri‐coordinated deprotonated/protonated 1,2,3‐triazoles. Channels with an inner diameter of 7.5 Å were found in 1, whereas a tunnel composed of stacking molecules with an inner diameter of 4.1 Å along the b‐axis exists in 2; it is occupied by free disordered methylamines, showing selective adsorption of O2 and CO2 at 25 °C. Obvious downfield shifts were observed by 13C NMR spectroscopies for methylamines inside the confined channels in 1 and 2. There are diversified pores in 3 and 4, which are formed by the molecules themselves and intermolecular accumulations. Adsorption tests indicate that 3 and 4 are fine adsorption materials for CH4 and CO2 under low pressure that rely on the environments built by the POMs. Correspondingly, 1 and 2 display reversible photoresponsive thermochromism that is subtlety influenced by the channels. The polyoxometalate organic frameworks (POMOFs) with multiple functional adsorptions are easy to assemble. Their photo‐/thermoresponse properties offer a new pathway for the self‐constructions of one‐off hybrid materials that possess the good properties of both POMs and MOFs.
Solid‐State Near‐Infrared Circularly Polarized Luminescence from Chiral YbIII‐Single‐Molecule Magnet
Authors: Lefeuvre Bertrand , Mattei Carlo Andrea , Gonzalez Jessica Flores , Gendron Frédéric , Dorcet Vincent , Riobé François , Lalli Claudia , Le Guennic Boris , Cador Olivier , Maury Olivier , Guy Stéphan , Bensalah‐Ledoux Amina , Baguenard Bruno , Pointillart Fabrice
Published: March 2021

A field‐induced chiral YbIII Single‐Molecule Magnet (SMM) displayed an unprecedented near‐infrared circularly polarized luminescence (NIR‐CPL) in the solid‐state. The bridging bis(1,10‐phenantro[5,6b])tetrathiafulvalene triad (L) allowed an efficient sensitization of the NIR 2F5/2→2F7/2 emission while the NIR‐CPL is associated to the f‐f transitions of the YbIII ion bearing chiral β‐diketonate derived‐camphorate ancillary ligands.
Room‐Temperature Phosphorescence Emitters Exhibiting Red to Near‐Infrared Emission Derived from Intermolecular Charge‐Transfer Triplet States of Naphthalenediimide−Halobenzoate Triad Molecules
Authors: Ono Toshikazu , Kimura Kazuki , Ihara Megumi , Yamanaka Yuri , Sasaki Miori , Mori Hirotoshi , Hisaeda Yoshio
Published: March 2021

Room‐temperature phosphorescence (RTP) emitters have attracted significant attention. However, purely organic RTP emitters in red to near‐infrared region have not been properly investigated. In this study, a series of naphthalenediimide−halobenzoate‐linked molecules are synthesized, one of which exhibits efficient RTP properties, showing red to near‐infrared emission in solid and aqueous dispersion. Spectroscopic studies and single‐crystal X‐ray diffraction analysis have shown that the difference in the stacking modes of compounds affects the optical properties, and the formation of intermolecular charge‐transfer complexes of naphthalenediimide−halobenzoate moiety results in a bathochromic shift of absorption and RTP properties. The time‐dependent density functional theory calculations showed that the formation of charge‐transfer triplet states and the external heavy atom effect of the halogen atom enhance the intersystem crossing between excited singlet and triplet states.
Divergent Syntheses of Pyridoacridine Alkaloids viaPalladium‐Catalyzed Reductive Cyclization with Nitro‐Biarenes
Authors: Liu Bo , Wang Shuping , Bian Changhao , Liao Hongze , Lin Hou‐Wen
Published: March 2021

Main observation and conclusion

A divergent and novel protocol for the preparation of both pyrido[2,3,4‐kl]acridine and pyrido[4,3,2‐kl]acridine alkaloids was developed. This method featured the remote palladium‐catalyzed reductive cyclization with Mo(CO)6 as reductant. A wide range of substrates including three types of nitro arenes were tolerated and afforded corresponding products in good to excellent yields. This method has been successfully applied to the total synthesis of norsegoline, styelsamine C and the skeleton of necatorone.
Identification of distinct phenotypic clusters in heart failure with preserved ejection fraction
Authors: Uijl Alicia , Savarese Gianluigi , Vaartjes Ilonca , Dahlström Ulf , Brugts Jasper J. , Linssen Gerard C.M. , van Empel Vanessa , Brunner‐La Rocca Hans‐Peter , Asselbergs Folkert W. , Lund Lars H. , Hoes Arno W. , Koudstaal Stefan
Published: March 2021

Aims

We aimed to derive and validate clinically useful clusters of patients with heart failure with preserved ejection fraction (HFpEF; left ventricular ejection fraction ≥50%).

Methods and results

We derived a cluster model from 6909 HFpEF patients from the Swedish Heart Failure Registry (SwedeHF) and externally validated this in 2153 patients from the Chronic Heart Failure ESC‐guideline based Cardiology practice Quality project (CHECK‐HF) registry. In SwedeHF, the median age was 80 [interquartile range 72–86] years, 52% of patients were female and most frequent comorbidities were hypertension (82%), atrial fibrillation (68%), and ischaemic heart disease (48%). Latent class analysis identified five distinct clusters: cluster 1 (10% of patients) were young patients with a low comorbidity burden and the highest proportion of implantable devices; cluster 2 (30%) patients had atrial fibrillation, hypertension without diabetes; cluster 3 (25%) patients were the oldest with many cardiovascular comorbidities and hypertension; cluster 4 (15%) patients had obesity, diabetes and hypertension; and cluster 5 (20%) patients were older with ischaemic heart disease, hypertension and renal failure and were most frequently prescribed diuretics. The clusters were reproduced in the CHECK‐HF cohort. Patients in cluster 1 had the best prognosis, while patients in clusters 3 and 5 had the worst age‐ and sex‐adjusted prognosis.

Conclusions

Five distinct clusters of HFpEF patients were identified that differed in clinical characteristics, heart failure drug therapy and prognosis. These results confirm the heterogeneity of HFpEF and form a basis for tailoring trial design to individualized drug therapy in HFpEF patients.
A Blue Zinc Complex of a Dioxobilin‐Type Pink Chlorophyll Catabolite Exhibiting Bright Chelation‐Enhanced Red Fluorescence
Authors: Li Chengjie , Podewitz Maren , Kräutler Bernhard
Published: March 2021

In senescent fall leaves and in ripening fruit, colorless phyllobilins (PBs) accumulate from breakdown of chlorophyll, from which yellow PBs (phylloxanthobilins) and pink colored PBs (phylloroseobilins) arise in some leaves. The first described PBs were formyloxobilin‐type PBs, but dioxobilin‐type PBs also occur naturally. Here we report the synthesis and characterization of the blue Zn(II) complex of a dioxobilin‐type pink PB, which chelates a Zn(II) ion fast and tightly in an effectively tridentate manner. The optically active Zn complex featured bright chelation enhanced red fluorescence and exhibited strikingly differing spectral properties in methanol and in acetonitrile. Computational studies based on DFT‐calculations gave detailed insights into low energy structures of the Zn complex in both solvents and provided support for the proposed role of solvent in the coordination sphere of the bound Zn(II) ion.