bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steric Effects in
ortho
CH Activation of Aromatic Systems
Authors: Novák Zoltán , Tóth Balázs L. , Stirling András 
Published: November 2022

Abstract

Transition metal‐catalyzed directed aromatic
ortho
CH activation offers many possibilities for the functionalization of various substrates having different directing groups. However, the reactivity of the substrate is determined by electronic and steric factors. Herein, we present and discuss a recently developed model which considers only the steric properties of the substrates to assess their reactivity in
ortho
CH activation in the presence of
ortho
substituents. Dihedral angle between the directing group and the aromatic ring influences the coordination and the CH activation elementary step, thus determine reactivities and the stability of metal‐complex intermediates. The presentation of the theoretical model is followed by several literature examples from substrates having borderline reactivities, to explore and describe the most interesting region of reactivity. The most commonly used directing groups are discussed taking into consideration their key structural elements, and reactivity trends are presented with the help of complex formation and reactions of each substrate group. The lack of transformation is also discussed by showing representatives of unreactive substrates.
CH Functionalization of Indazoles
Authors: Kumar Anil , Sakhuja Rajeev 
Published: November 2022

Abstract
The indazole is an important class of bicyclic nitrogen‐containing heterocycle that forms the core structure of a large number of compounds with potential therapeutic value. Consequently, CH functionalization of this scaffold has been extensively explored using transition metal‐catalyzed and metal‐free CH functionalization strategies. This article provides a perspective on various strategies that have been developed to add a substituent on this heterocycle core and their appropriate coupling partners.
Intra‐ and Inter‐Molecular Carbene and Nitrene Insertion by Metalloenzymes into CH Bond
Authors: Mukherjee Prasun , Jain Shubhanshu , Al‐Thabaiti Shaeel A. , Mokhtar Mohamed , Maiti Debabrata 
Published: November 2022

Abstract
Enzymes provide a uniquely crafted chiral environment for a reaction to proceed in high selectivity and catalytic activity. However, enzymes are very substrate‐specific and thus provide little use in synthetic settings where broad substrate applicability is desirable. (i) Modifying an enzyme, either through modification of some residues or by installing a nonnative transition metal complex, can broaden the substrate scope and allow nonnatural transformations while increasing the activity and selectivity of small‐molecule catalysis. Coupled with the recent advances in genetic engineering and directed evolution method, (ii) modifying enzymes as per the requirement is getting more accessible. These modifications are resulting in increased attention to the enzymatic catalysis field, some even replacing established organometal‐catalyzed industrial processes. (iii) However, even with improvement in such techniques, creating an abiotic reaction from a noncatalytic scaffold remains a significant limitation.
Ag‐, Au‐, and Pt‐Catalyzed CH Functionalization
Authors: Xiong Heng‐Ying , Zhang Guangwu , Elsaid Mazen , Ge Haibo 
Published: November 2022

Abstract

This article summarizes the recent advances in Ag‐, Au‐, and Pt‐catalyzed CH functionalizations. First, a systemic collection of Ag‐catalyzed CH functionalization reactions classified into CspH, Csp
2
H, and Csp
3
H functionalizations is presented. These reactions proceed through nitrene transfer, carbene transfer, radical intermediacy, or other pathways. Some mechanistic discussions on selected transformations are provided, especially for the radical processes. Next, gold‐catalyzed CH reactions starting with Csp
3
H functionalization are described. Early gold‐catalyzed CH functionalization processes often involved nitrene transfer, carbene transfer, or redox processes. The mechanistic aspects of gold‐catalyzed reactions involving novel intermediates are also discussed. Finally, a survey of Pt‐catalyzed CH functionalization reactions, albeit limited in examples when compared to Ag‐ and Au‐catalyzed processes, is provided.
Bioinspired C(sp
3
)H Functionalization by High‐Valent Iron/Manganese Oxo Complexes and Applications in Organic Syntheses
Authors: Wan Yanjun , Tan Liming , Wu Keyang , Li Gang 
Published: November 2022

Abstract
The direct functionalization of aliphatic CH bonds has emerged as a versatile strategy to convert chemical feedstocks to higher‐value chemicals. Nature performs aliphatic CH functionalization reactions with impressive efficiency and selectivity using iron‐dependent heme and nonheme enzymes. The reaction proceeds through a radical pathway via H· abstraction by high‐valent metal oxo species. Chemists have used well‐defined iron and manganese complexes as artificial catalysts to mimic the functions of the enzymatic systems. By regulating and tuning the ligands, almost a full spectrum of enzymatic reactivity on CH functionalization can be replicated. By virtue of their potential application in synthetic chemistry, CH oxidations and halogenations have sparked numerous interests in the past two decades. This article summarizes the recent progress on CH oxidations and halogenations using heme and nonheme iron and manganese catalysts. Specific attention is given to reactions under synthetically applicable conditions. Strategies for tuning the reactivity and selectivity of CH functionalization reactions were discussed. These discoveries are expected to enable the further application of CH functionalization reactions in synthetic chemistry, particularly the emerging late‐stage diversifications of complex molecules that can be ultimately utilized in the pharmaceutical industry.
Metal‐Catalyzed Annulations via Activation of Alkenyl CH Bonds
Authors: Cendón Borja , González José Manuel , Mascareñas José Luis , Gulías Moisés 
Published: November 2022

Abstract

Annulations initiated by CH activation processes have emerged as powerful tools for the synthesis of cyclic compounds from acyclic precursors, in a straightforward, direct, and atom efficient way. Traditionally, most of these annulations involve the activation of C(sp
2
)H bonds in aromatic compounds; but, more recently, this chemistry is also being extended to alkenes, which is highly attractive, but also challenging, because it requires to avoid side reactivity pathways typical of double bonds. In this article, we revise the more relevant advances in the field together with an explanation of key mechanistic features of each type of reaction.
Transition Metal‐Catalyzed Oxidative Cross‐Coupling Between Olefins
Authors: Jiang Bing , Xu Yun‐He 
Published: November 2022

Abstract
Transition metal‐catalyzed oxidative dehydrogenative cross‐coupling of alkenes represents an atom‐ and step‐economical approach to access valuable diene derivatives that are frequently displayed in natural products and medicinal agents. This article details the recent developments in the transition metal‐catalyzed CH bond alkenylation of olefins.
Metal‐Free CH Functionalization for the Synthesis of Pyrrole, Pyridine, and Pyrimidine
Authors: Borah Gongutri , Borah Ashwini , Banik Bimal K. 
Published: November 2022

Abstract
Heterocycles receive great attention because of their versatile properties as pharmacophores. Among these heterocycles, the biological activities, reactions, and synthesis of pyrrole‐, pyridine‐, and pyrimidine‐containing molecules are most important as they serve as a field of research in heteroaromatic chemistry. These scaffolds not only have a great presence in a broad range of drug molecules but are also found as pervasive shreds of several vitamins, pharmaceutically important natural products, synthetic drug candidates, and biomolecules. In this article, we summarize a diverse range of metal‐free CH functionalization approaches for the synthesis of pyrrole, pyridine, pyrimidine, and their derivatives.
Tandem CH/CO Activation as New Paradigm for Molecular Synthesis
Authors: Wang Ting‐Hsuan , Hung Chen‐Hsun , Ong Tiow‐Gan 
Published: November 2022

Abstract
Over the last two decades, phenolic or alcoholic derivatives have been slowly evolved as conceivable replacements to the ubiquitous aryl halides (I, Br, and Cl) in the carbon–carbon cross‐coupling reaction. Nonetheless, there is a daunting challenge in the adoption of CO activation as the toolkit in sustainable molecular synthesis, owing to the high dissociation energy to break the CO bond, thus limiting the scope of reactions for broader application. Therefore, cross‐coupling reaction by incorporating CH bond activation into CO manifold might enrich the reactivity and expand the chemical space for more complex molecule. This article will discuss the reaction methodology and mechanism concerning about nickel and palladium‐promoted tandem CH/CO bond activation for the cross‐coupling reaction.
CH Functionalization Reactions of Heterocycles via Carbene Transfer Reactions
Authors: Empel Claire , Koenigs Rene M. 
Published: November 2022

Abstract
Carbene transfer reactions of diazoalkanes are a powerful tool for the direct CH functionalization of heterocycles. Diazoalkanes have proven as excellent precursors to access free or metal‐bound carbene intermediates with molecular nitrogen as the sole by‐product. Herein, we describe carbene transfer reactions for the selective CH functionalization of heterocycles such as pyrrole, indole, or carbazole. Developments in metal‐catalyzed and light‐mediated approaches will be discussed in detail.
An Intelligent Nanoplatform for Orthotopic Glioblastoma Therapy by Nonferrous Ferroptosis
Authors: Cao Yue , Zhang Shuai , Lv Zhijia , Yin Na , Zhang Hao , Song Peizhe , Zhang Tianqi , Chen Yong , Xu Haiyang , Wang Yinghui , Liu Xinrui , Zhao Gang , Zhang Hongjie 
Published: November 2022

AbstractFerroptosis, characterized by iron accumulation and lipid peroxidation (LPO), can avoid the intrinsic apoptotic resistance of tumor cells and have been explored for glioblastoma (GBM) therapy. However, the direct delivery of iron species may trigger severe adverse side effects. Using nonferrous species to induce LPO‐mediated ferroptosis maybe a promising strategy for GBM treatment, but there is still no report till now. Therefore, in this study, first an intelligent blood–brain barrier (BBB)‐permeable nanoplatform (PCN‐224@Au/CeO2‐Lf) is constructed for efficient nonferrous ferroptosis‐involved orthotopic GBM therapy. Porous coordination network‐224 nanoparticles (PCN‐224 NPs) are served as sonosensitizers for sonodynamic therapy (SDT). In situ growth of small Au NPs with glucose oxidase (GOx)‐mimic activity and CeO2 NPs with peroxidase (POD)‐ and catalase (CAT)‐mimic abilities are applied for H2O2 self‐supplement, more acidic microenvironment, and generation of cytotoxic hydroxyl radical (·OH) and O2, which improves the efficacy of SDT. Besides, Ce4+‐mediated glutathione (GSH) depletion further promotes ferroptosis and apoptosis. Reactive oxygen species (ROS) burst and GSH consumption‐related glutathione peroxidase 4 (GPX4) deactivation promote the accumulation of LPO, leading to significant nonferrous ferroptosis, which can effectively shrink the orthotopic GBM. These findings first demonstrate the nonferrous ferroptosis strategy for efficient GBM treatment.
Stable Anode‐Free All‐Solid‐State Lithium Battery through Tuned Metal Wetting on the Copper Current Collector
Authors: Wang Yixian , Liu Yijie , Nguyen Mai , Cho Jaeyoung , Katyal Naman , Vishnugopi Bairav S. , Hao Hongchang , Fang Ruyi , Wu Nan , Liu Pengcheng , Mukherjee Partha P. , Nanda Jagjit , Henkelman Graeme , Watt John , Mitlin David 
Published: November 2022

AbstractA stable anode‐free all‐solid‐state battery (AF‐ASSB) with sulfide‐based solid‐electrolyte (SE) (argyrodite Li6PS5Cl) is achieved by tuning wetting of lithium metal on “empty” copper current‐collector. Lithiophilic 1 µm Li2Te is synthesized by exposing the collector to tellurium vapor, followed by in situ Li activation during the first charge. The Li2Te significantly reduces the electrodeposition/electrodissolution overpotentials and improves Coulombic efficiency (CE). During continuous electrodeposition experiments using half‐cells (1 mA cm−2), the accumulated thickness of electrodeposited Li on Li2Te–Cu is more than 70 µm, which is the thickness of the Li foil counter‐electrode. Full AF‐ASSB with NMC811 cathode delivers an initial CE of 83% at 0.2C, with a cycling CE above 99%. Cryogenic focused ion beam (Cryo‐FIB) sectioning demonstrates uniform electrodeposited metal microstructure, with no signs of voids or dendrites at the collector‐SE interface. Electrodissolution is uniform and complete, with Li2Te remaining structurally stable and adherent. By contrast, an unmodified Cu current‐collector promotes inhomogeneous Li electrodeposition/electrodissolution, electrochemically inactive “dead metal,” dendrites that extend into SE, and thick non‐uniform solid electrolyte interphase (SEI) interspersed with pores. Density functional theory (DFT) and mesoscale calculations provide complementary insight regarding nucleation‐growth behavior. Unlike conventional liquid‐electrolyte metal batteries, the role of current collector/support lithiophilicity has not been explored for emerging AF‐ASSBs.
STING Suppresses Mitochondrial VDAC2 to Govern RCC Growth Independent of Innate Immunity
Authors: Zhu Zhichuan , Zhou Xin , Du Hongwei , Cloer Erica W. , Zhang Jiaming , Mei Liu , Wang Ying , Tan Xianming , Hepperla Austin J. , Simon Jeremy M. , Cook Jeanette Gowen , Major Michael B. , Dotti Gianpietro , Liu Pengda 
Published: November 2022

AbstractSTING is an innate immune sensor for immune surveillance of viral/bacterial infection and maintenance of an immune‐friendly microenvironment to prevent tumorigenesis. However, if and how STING exerts innate immunity‐independent function remains elusive. Here, the authors report that STING expression is increased in renal cell carcinoma (RCC) patients and governs tumor growth through non‐canonical innate immune signaling involving mitochondrial ROS maintenance and calcium homeostasis. Mitochondrial voltage‐dependent anion channel VDAC2 is identified as a new STING binding partner. STING depletion potentiates VDAC2/GRP75‐mediated MERC (mitochondria‐ER contact) formation to increase mitochondrial ROS/calcium levels, impairs mitochondria function, and suppresses mTORC1/S6K signaling leading to RCC growth retardation. STING interaction with VDAC2 occurs through STING‐C88/C91 palmitoylation and inhibiting STING palmitoyl‐transferases ZDHHCs by 2‐BP significantly impedes RCC cell growth alone or in combination with sorafenib. Together, these studies reveal an innate immunity‐independent function of STING in regulating mitochondrial function and growth in RCC, providing a rationale to target the STING/VDAC2 interaction in treating RCC.
CRISPR/Cas12a‐Enabled Multiplex Biosensing Strategy Via an Affordable and Visual Nylon Membrane Readout
Authors: Hu Tao , Ke Xinxin , Li Wei , Lin Yu , Liang Ajuan , Ou Yangjing , Chen Chuanxia 
Published: November 2022

AbstractMost multiplex nucleic acids detection methods require numerous reagents and high‐priced instruments. The emerging clustered regularly interspaced short palindromic repeats (CRISPR)/Cas has been regarded as a promising point‐of‐care (POC) strategy for nucleic acids detection. However, how to achieve CRISPR/Cas multiplex biosensing remains a challenge. Here, an affordable means termed CRISPR‐RDB (CRISPR‐based reverse dot blot) for multiplex target detection in parallel, which possesses the advantages of high sensitivity and specificity, cost‐effectiveness, instrument‐free, ease to use, and visualization is reported. CRISPR‐RDB integrates the trans‐cleavage activity of CRISPR‐Cas12a with a commercial RDB technique. It utilizes different Cas12a‐crRNA complexes to separately identify multiple targets in one sample and converts targeted information into colorimetric signals on a piece of accessible nylon membrane that attaches corresponding specific‐oligonucleotide probes. It has demonstrated that the versatility of CRISPR‐RDB by constructing a four‐channel system to simultaneously detect influenza A, influenza B, respiratory syncytial virus, and SARS‐CoV‐2. With a simple modification of crRNAs, the CRISPR‐RDB can be modified to detect human papillomavirus, saving two‐thirds of the time compared to a commercial PCR‐RDB kit. Further, a user‐friendly microchip system for convenient use, as well as a smartphone app for signal interpretation, is engineered. CRISPR‐RDB represents a desirable option for multiplexed biosensing and on‐site diagnosis.
Glutathione‐Responsive Nanoparticles of Camptothecin Prodrug for Cancer Therapy
Authors: Zhang Lingpu , Zhu Lin , Tang Lin , Xie Jiayi , Gao Yajuan , Yu Changyuan , Shang Kun , Han Hongbin , Liu Chaoyong , Lu Yunfeng 
Published: November 2022

AbstractCamptothecin (CPT) is a potent chemotherapeutic agent for various cancers, but the broader application of CPT is still hindered by its poor bioavailability and systemic toxicity. Here, a prodrug that releases CPT in response to glutathione (GSH), which is commonly overexpressed by cancer cells is reported. Through assembling with PEGylated lipids, the prodrug is incorporated within as‐assembled nanoparticles, affording CPT with a prolonged half‐life in blood circulation, enhanced tumor targetingability, and improved therapeutic efficacy. Furthermore, such prodrug nanoparticles can also promote dendritic cell maturation and tumor infiltration of CD8+ T cells, providing a novel strategy to improve the therapeutic efficacy of CPT.
Process coupling of CO2 and glycerol comprehensive utilization based on anionic 2D nanomaterial
Authors: Gao Mingyu , Fan Jiaxuan , Fan Jingjing , Wang Qian , Li Dianqing , Feng Junting 
Published: November 2022

AbstractWe developed an approach to realize the comprehensive utilization of CO2 and glycerol by smartly design a nanocatalyst, which concerns the coupling of catalytic reactions and the separation or capture process. Specifically, MgFe‐CO32−‐LDHs with different thickness were fabricated by employing atmospheric CO2 as carbon source and an atomic‐level interface was constructed by introducing Pt single atoms to obtain series of Pt/MgFe‐LDHs nanocatalysts. During a catalytic assessment, the CO32− confined within interlayer was in situ converted when integrated with glycerol oxidation under irradiation. The optimal nanocatalyst exhibited a decent conversion efficiency of CO32−‐CO‐CH4 and near 100% selectivity of secondary hydroxy group in glycerol. DFT calculation, isotope‐labeled experiments and in situ spectrograph characterization revealed possible coupling reaction mechanism. More importantly, the nanocatalyst exhibited impressive reusability for at least six 6 runs. The developed multiple coupling process will be an alternative and promising procedure for the waste and low‐valued sources synergetic utilization.
Emerging Lithiated Organic Cathode Materials for Lithium‐Ion Full Batteries
Authors: Lu Yong , Zhang Qiu , Li Fujun , Chen Jun 
Published: November 2022

AbstractOrganic electrode materials have application potential in lithium batteries owing to their high capacity, abundant resources, and structural designability. However, most reported organic cathodes are at oxidized states (namely unlithiated compounds) and thus need to couple with Li‐rich anodes. In contrast, lithiated organic cathode materials could act as a Li reservoir and match with Li‐free anodes such as graphite, showing great promise for practical full‐battery applications. Here we summarize the synthesis, stability, and battery applications of lithiated organic cathode materials, including synthetic methods, stability against O2 and H2O in air, and strategies to improve comprehensive electrochemical performance. Future research should be focused on new redox chemistries and the construction of full batteries with lithiated organic cathodes and commercial anodes under practical conditions. This Minireview will encourage more efforts on lithiated organic cathode materials and finally promote their commercialization.
Accelerated‐curing epoxy structural film adhesive for bonding lightweight honeycomb sandwich structures
Authors: Zhao Liwei , Li Hongfeng , Qiao Yingjie , Bai Xuefeng , Wang Dezhi , Qu Chunyan , Xiao Wanbao , Liu Ye , Zhang Jian 
Published: November 2022

AbstractAccelerating the curing of epoxy/aromatic amine adhesives and improving their toughness are challenges in heat‐resistant epoxy structural adhesives. Herein, we report an epoxy/aromatic amine adhesive accelerated curing system with an oxo‐centered trinuclear (chromium III) complex, which is toughened using a thermoplastic block copolymer (TPBC). The reaction characteristics, heat resistance, microstructure, and bonding properties of the accelerated epoxy adhesives were analyzed. The reaction peak temperature of the epoxy with 3% catalyst was 113.1°C, which was 113.6°C lower than that of epoxy without catalyst, and the modified epoxy resin demonstrated a potential for rapid curing at medium temperature. The glass transition temperature of the TPBC‐toughened epoxy adhesive was 125°C after curing, indicating excellent thermal stability after medium temperature curing. The introduction of the TPBC increased the single‐lap shear strength of the epoxy adhesive without reducing its heat resistance. The shear strength at room temperature and 120°C of the modified epoxy adhesive with 50 phr of TPBC was 25.2 and 10.9 MPa, respectively. Moreover, the epoxy film adhesive exhibited outstanding bonding properties when used in the bonding of lightweight honeycomb sandwich structures.
New chimeric HDAC inhibitors for the treatment of colorectal cancer
Authors: Bär Sofia I. , Pradhan Rohan , Biersack Bernhard , Nitzsche Bianca , Höpfner Michael , Schobert Rainer 
Published: November 2022

AbstractColorectal cancer is the third most common cause of cancer‐associated deaths due to a high recurrence rate and an increasing occurrence of resistance to established therapies. This highlights the importance of developing new chemotherapeutic agents. The current study focuses on cancer‐specific targets such as apoptosis‐inhibiting survivin, which distinguishes cancer cells from healthy tissue. A combination of pharmacophores of established anticancer agents to afford chimeric pleiotropic chemotherapeutic agents was tested on this cancer entity. We analysed the effects of the dual mode anticancer agents, animthioxam, brimbam, troxbam, and troxham, as well as their structural congeners suberoylanilide hydroxamic acid and combretastatin A‐4 on human cancer cell lines. Their cytotoxicity was determined using the MTT assay, further techniques for detecting apoptotic events, cell cycle analyses, clonogenic and wound healing assays, immunostaining, histone deacetylase (HDAC) activity measurements, and Western blot analysis for the detection of survivin expression in HCT116 colon cancer cells. Molecular docking studies were conducted to assess potential molecular targets of the test compounds. The test compounds were found selectively cytotoxic toward cancer cells by inducing apoptosis. The metastatic potential was effectively reduced by disruption of the microtubular cytoskeleton. The test compounds were also proven to be general HDAC inhibitors and to lead to reduced survivin expression.