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Metal‐organic frameworks (MOFs) have been extensively studied and applied as promising active materials in the field of energy storage and conversion. Recently, conductive π‐d conjugated coordination polymers (CCPs) have garnered significant attention due to their high conductivity, high porosity, tunable components, and adjustable pore sizes. These CCPs typically consist of transition metal ions and organic ligands, forming an in‐plane π‐d conjugated system. In this review, a concise summary of the design principles are provided, synthesis methods, and reaction mechanisms of CCPs as electrodes for energy storage systems, including metal‐ion batteries and supercapacitors. In addition, several novel energy storage applications are highlighted, such as metal‐air batteries and photo‐enhanced batteries. Finally, the challenges that need to be addressed is discussed urgently and offer perspectives on the further application of CCPs in more advanced energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

A free-standing highly porous graphitic scaffold of S was fabricated via intercalating microcellulose fibers into graphene oxide (GO) nanosheets, followed by high-temperature carbonization. The abundant porous architecture formed between graphene nanosheets with microcellulose (Cel@Gra) is capable of accommodating sufficient S and buffering S volumetric changes during redox reactions. Moreover, those unstacked graphitic nanosheets inherited the high surface area of GO, and thus offered numerous transmitting routes of both electrons and ions. Upon incorporation of S by Cel@Gra conductive scaffolds, the as-prepared lithium–sulfur battery (LSB) cathodes delivered much higher capacity and superior rate capability in comparison with its pure graphite counterpart. The superior electrochemical behaviors of S/Cel@Gra can be ascribed to the strong adsorption of Cel@Gra toward polysulfides and the enhanced reactive kinetics during charge/discharge. This work provides a sustainable, up-scalable, and cost-effective microcellulose in designing and fabricating high-performance LSB cathodes. [ABSTRACT FROM AUTHOR]

A tandem carbonyl reduction and hydrodefluorination of β‐trifluoromethyl enones with hydrosilanes under transition‐metal‐free conditions was developed for the synthesis of a variety of valuable gem‐difluorovinyl alcohols. The hydrosilane could act as both a reductive agent and a C(sp3)‐F bond‐breaking promoter under mild reaction conditions. Synthetically useful organofluorides, such as gem‐fluorophosphine alkene, gem‐difluorovinyl ketone, and fluorinated dihydrofuran derivatives could be readily constructed by further transformations of the obtained gem‐difluorovinyl alcohols. Moreover, the method features mild reaction conditions, operational simplicity, excellent functional group tolerance, and scalability. [ABSTRACT FROM AUTHOR]

A H2O-promoted and (NH4)2CO3-enabled deiodoamination and defluoroiminization reaction of fluoroalkyl alkenes has been developed under transition-metal-free conditions. Structurally important fluoroalkylated 1,5-diazapentadienes were obtained in excellent Z-selectivity with good functional group tolerance. The versatility of the method was illustrated in the synthesis of valuable organofluorides from the obtained products. Compared to traditional synthetic methods, several apparent limitations, including distillation for purification, multistep manipulation, harsh reaction conditions, moisture exclusion, and the use of toxic/sensitive reagents, could be avoided. The key to the success of the reaction is the use of (NH4)2CO3 as a commercially available, inexpensive, low-toxic, and efficient NH2/NH source and water as a C(sp3)–F bond cleavage promoter. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents on substrates are also vital for enhancing the reaction efficiency. [ABSTRACT FROM AUTHOR]

The distinctive hydrophobic hydration effect in the aqueous solution contributes to the success of the phospha‐Michael reaction between β‐CF3‐β,β‐disubstituted enones and diarylphosphine oxides, providing an access to biologically relevant γ‐ketophosphine oxides bearing a sterically highly congested CF3‐ and P(O)‐tetrasubstituted carbon center. More importantly, the resulting products could be further transformed into densely functionalized γ‐ketophosphine oxides containing a CF3‐ and P(O)‐tetrasubstituted carbon center. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is an age‐related neurodegenerative disorder characterized by amyloid‐β (Aβ) deposition and neurofibrillary tangles. Although the NAD+‐dependent deacetylases SIRT1 and SIRT2 play pivotal roles in age‐related diseases, their cooperative effects in AD have not yet been elucidated. Here, we report that the SIRT2:SIRT1 ratio is elevated in the brains of aging mice and in the AD mouse models. In HT22 mouse hippocampal neuronal cells, Aβ challenge correlates with decreased SIRT1 expression, while SIRT2 expression is increased. Overexpression of SIRT1 prevents Aβ‐induced neurotoxicity. We find that SIRT1 impedes SIRT2‐mediated APP deacetylation by inhibiting the binding of SIRT2 to APP. Deletion of SIRT1 reduces APP recycling back to the cell surface and promotes APP transiting toward the endosome, thus contributing to the amyloidogenic processing of APP. Our findings define a mechanism for neuroprotection by SIRT1 through suppression of SIRT2 deacetylation, and provide a promising avenue for therapeutic intervention of AD. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) are an emerging group of persistent organic pollutants in aquatic environments with high levels of toxicity and bioaccumulation. The risks posed by PFASs to the environment and health have attracted increasing attention. To remove them from water, advanced oxidation processes (AOPs), with the merits of high efficiency and low cost, are mainly used. Photo/electrocatalytic heterogeneous AOPs, with the assistance of nanostructured catalysts and external energy in the form of light/electricity, have emerged as one of the most powerful techniques, overcoming the difficulty associated with defluorination and achieving the effective and complete degradation of PFASs in water. The structures of photo/electrocatalysts play a critical role in the production of reactive oxygen species, the electron transfer process, and the degradation pathway and its efficiency. Herein, to elucidate the structure–performance relationship, a review of photo/electrocatalysts for the enhanced degradation of PFASs in heterogeneous AOPs, organized according to their composition and nanostructure design, is provided. This review article is mainly focused on (1) the mechanisms and pathways of PFAS degradation by heterogeneous photo/electrocatalytic AOPs, and (2) the structural designs and modifications of photo/electrocatalysts for the enhanced degradation of PFASs by heterogeneous AOPs. Finally, the challenges and prospects for future research into photo/electrocatalysts of heterogeneous AOPs in the field of PFAS remediation are discussed. [ABSTRACT FROM AUTHOR]

The distinctive fluorine effects on "on-water" chemistry have remained less explored. In this work, an "on-water" reaction of β-trifluoromethylated enones with phosphine oxides was developed for the preparation of highly functionalized gem-difluorodienes with excellent Z-selectivity. The reaction occurred through a well-designed tandem phospha-Brook rearrangement and defluorination sequence under transition-metal-free conditions in water solution, which efficiently overcame some competitive side reactions, such as hydrodefluorination, 1,4-nucleophilic addition, and phosphorylation. The success was attributed to favorable H-bonding interactions at the water–organic phase boundary which could activate the substrates and enhance the reaction selectivity. [ABSTRACT FROM AUTHOR]

A step‐economical and operationally simple nickel‐catalyzed cross‐electrophile coupling of aryl phosphates with aryl bromides through C−O bond cleavage, which precluded the employment of relatively moisture‐labile and unreadily available organometallics, was developed. The reaction proceeded smoothly in the presence of magnesium turnings and lithium chloride in THF to afford the corresponding biaryls in moderate to good yields with reasonable functionality tolerance. [ABSTRACT FROM AUTHOR]

Herein, we report the rhodium-catalyzed domino arylation/cyclization reaction of unactivated internal alkynes to afford the optically active indenols in excellent yields (up to 92%) and extremely high enantioselectivities (up to 99% ee) in the presence of new amide substituted chiral diene ligands. Notably, a total of 21 new chiral diene ligands are synthesized, which are potential choices for other asymmetric reactions. [ABSTRACT FROM AUTHOR]

An aerobic coupling of benzhydryl phosphonium salts with simple alkenes for accessing trisubstituted olefins is developed under metal‐free, catalyst‐free, and additive‐free conditions. New C(sp3)−C(sp2) bond is constructed via the C−P and C−H bond functionalization by synergistically using O2 as a "green" oxidant and DMSO as a promoter. The method also distinguishes itself by its broad substrate scope and synthetic potential. Particularly, the use of 1,3,5‐trimethoxybenzene fragment in the resulting products as a carbon‐based leaving group for further transformations is proved to be feasible. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) have been considered as one of the most promising energy storage systems owing to their high theoretical energy density and abundant sulfuric resources. However, their commercial application is limited by rapid capacity decline and low Coulombic efficiency. Metal–organic frameworks (MOFs) made of metallic nodes and organic ligands can suppress polysulfide shuttling and promote redox kinetics. In this paper, the effects of crystallographic dimensions and metallic categories on chemical performance of LSBs have been meticulously explored electrochemical performance. As a result, exposed Ni active sites in a lamellar Ni‐MOF was found to deliver a superior electrochemical performance. The as‐assembled LSBs with 2D‐Ni‐MOF/CNTs cathode deliver a much superior initial discharge capacity, (820 mAh g−1 at 0.5 C), and exhibit excellent cycling stability over 550 cycles than those analogues of 3D stereoscopic Ni‐MOF and 2D lamellar Co‐MOF. This work proposed a perspective in elevating LSBs performance through synergistic optimization of the MOFs dimensions and the metallic nuclei in the cathodes. [ABSTRACT FROM AUTHOR]

Access to regioselective monofluorinated alkenes concurrently from fluoroalkenylating building blocks such as gem-difluorocyclopropanes represents a powerful synthetic tool and yet a longstanding challenge. Herein, we report a regiodivergent defluorinative carboxylation of gem-difluorocyclopropanes achieved by subtly modulating the electrochemical conditions. A range of branched and linear monofluoroalkene carboxylic acids were produced in moderate to high isolated yields and with exclusive regioselectivities. The protocol was designed to be "green", by using atmospheric CO2 as the C1 source and not using transition metals. It was also found to be scalable and applicable to late-stage functionalization of complex compounds. [ABSTRACT FROM AUTHOR]

Research interest in defluorinative functionzalization by means of the distinctive fluorine effect of organofluorides has led to rapid development in this topic. Herein, we reported an unprecedented four-component defluorinative reaction of allylic fluorides, amidines, and Cs2CO3 for the convenient synthesis of valuable pyrimidine-containing amidino carbamates under transition-metal-free conditions. The synthetic linchpin for realizing the multi-bonding tandem protocol relied on the directed function of the α-positioned hydroxyl group and the activating effect of the perfluoroalkyl substituent in allylic fluorides. Moreover, cesium carbonate served as a green carbonyl equivalent for formal CO capture. Mechanistic studies revealed that the reaction proceeded via a possible cyclic carbonate intermediate. [ABSTRACT FROM AUTHOR]

A green and sustainable electrochemical hydroboration of carbonyl compounds with HBpin has been reported for the first time. Under catalyst-free and additive-free mild reaction conditions the corresponding boronic esters were obtained in excellent yields via the simple electrochemical hydroboration of various aldehydes and ketones with HBpin at room temperature. The scale-up reaction demonstrated potential practical applications. A plausible reaction mechanism was proposed based on the corresponding deuterium-labelling, radical inhibition and cyclic voltammetry experiments. [ABSTRACT FROM AUTHOR]

An efficient transition-metal-free hydrodefluorination reaction of trifluoromethyl alkenes for accessing gem-difluoroalkenes is developed. It was surprising to find that the phosphoryl anion is able to mediate the defluorination. The successful realization of the reaction could also be attributed to the utility of water as an eco-friendly promoter. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC), sustainable biomass, has long been envisioned as a fantastic biomass material since it was discovered by Brown in 1886. BC cultivated in static medium appears as a never-dried hydrogel, wherein numerous nanofibers are highly interconnected, building into a three-dimensional (3D) architecture. Although BC has achieved great success in the area of biological medicine, the electronic inertness and susceptible bio-invasion restrict its further applications demanding electronic migration and durability. Carbonization has been employed to endow BC with superior conductivity and chemical tolerance without destroying the 3D architecture. Moreover, carbonized BC (CBC) exhibits exceptional properties such as ultralightweight, high surface area, good volumetric resilience, and superhydrophobicity, which are necessary for electrochemical energy, microwave attenuation, and selective absorption. The industrial production of BC facilitates the massive fabrication of high value-added CBC with low-cost precursors. This review summarizes the latest developments on the CBC-based functional materials, including state-of-the-art design concepts and synthetic strategies. Our prospects on the major obstacles in the approach of further exploitation of CBC, as well as the promising avenues in front of these issues are proposed in this review. [ABSTRACT FROM AUTHOR]

Morphine is a key drug for the treatment of pain but its side effects limit its clinical application. MEL‐0614, an endomorphin‐1 analog, has fewer side effects than morphine in addition to its powerful analgesic effect. In this study, we measured the effect of morphine and MEL‐0614 on hyperalgesia (7 days) and neuropathic allodynia (14 days) after thermal, mechanical, and cold stimulation. We found that after four and eight consecutive days of intrathecal administration (1, 3, and 10 nmol), morphine induced severe hyperalgesia and neuropathic allodynia, respectively. MEL‐0614 did not induce hyperalgesia at low doses (1 and 3 nmol) and had a mitigating effect on morphine‐induced neuropathic exacerbations in spared nerve injury mice. Hyperalgesia was blocked by Dynorphin A (1–17) antibody but not by an opioid receptor antagonist. To explore the reasons for the different results of morphine and MEL‐0614, we used quantitative PCR and immunofluorescence to explore the effects of both on N‐methyl‐D‐aspartate (NMDA) receptor subtype 2B (NR2B), microglia marker iba‐1, and inflammatory mediators. After 8 days of consecutive administration, morphine (10 nmol) promoted an increase in the number of NR2B, iba‐1, and inflammatory mediators in the spinal cord of mice. MEL‐0614 (10 nmol) had no significant effect on these factors, and after co‐administration with morphine, the expression of NR2B, iba‐1, and inflammatory mediators was lower than that with morphine injection alone. Our research showed the advantage of MEL‐0614 in terms of hyperalgesia and neuropathic allodynia, which may provide clinical relief of hyperalgesia and neuropathic allodynia caused by morphine. [ABSTRACT FROM AUTHOR]

A low-valent magnesium(I) complex [(XylNacnac)Mg]2 was employed as a highly efficient precatalyst for the hydroboration of a variety of cyclic and linear organic carbonates, polycarbonates, CO2 and esters with HBpin under mild conditions. The resultant boronates can be used for the preparation of the corresponding value-added diols, triols or alcohols through hydrolysis. [ABSTRACT FROM AUTHOR]

The hydroboration of a wide range of ketones with pinacolborane can be achieved under catalyst-free and solvent-free conditions to provide the corresponding boronic esters in quantitative yields. A large gram-scale hydroboration of acetophenone with HBpin under the same conditions was also performed to afford the alcohol product in a high yield thus demonstrating the scalability of the newly developed simple protocol. [ABSTRACT FROM AUTHOR]

The sterically bulky Schiff-base ligand 1 (L1H) was treated with CH3MgI in toluene to give the unexpected homoleptic magnesium complex 2 (L1MgL1) in good yield. However, the reaction of sterically more bulky ligand 3 (L2H) with CH3MgI in diethyl ether yielded the desired heteroleptic magnesium iodide 4 [L2MgI(OEt2)], which was further reduced with sodium to produce the Mg-Na heterodimetallic complex 5. The crystal structures of all new magnesium complexes were determined by single-crystal X-ray diffraction. All new magnesium complexes have been investigated as catalysts for the hydrosilylation of ketones with (EtO)3SiH. The study showed that catalytic activity of the Mg-Na dimetallic complex 5 is superior to those of monometallic magnesium complexes 2 and 4 and is applicable to a series of subatrates. [ABSTRACT FROM AUTHOR]

A new methyl-functionalized metal-organic framework, {Cu3(CMPEIP)2 ·2H2O} n {m-NB13, H3CMPEIP = 5-[(4-carboxy-2-methylphenyl)ethynyl]isophthalic acid} was solvothermally synthesized and structurally characterized. {Cu3(CMPEIP)2 ·2H2O} n exhibits a high BET surface area of 3215.4 m2 g-1, a large H2 uptake (1.92 wt.-% at 0.1 MPa and 77 K), and excellent CO2 storage capacity (9.24 wt.-% at 0.1 MPa and 298 K). [ABSTRACT FROM AUTHOR]

Wnt/β-catenin signaling pathway plays a major role in the cancer metastasis. Several microRNAs (miRNAs) are contributed to the inhibition of breast cancer metastasis. Here, we attempted to find novel targets and mechanisms of microRNA-100 (miR-100) in regulating the migration and invasion of breast cancer cells. In this study, we found that miR-100 expression was downregulated in human breast cancer tissues and cell lines. The overexpression of miR-100 inhibited the migration and invasion of MDA-MB-231 breast cancer cells. Inversely, the downregulation of miR-100 increased the migration and invasion of MCF-7 breast cancer cells. Furthermore, FZD-8, a receptor of Wnt/β-catenin signaling pathway, was demonstrated a direct target of miR-100. The overexpression of miR-100 decreased the expression levels not only FZD-8 but also the key components of Wnt/β-catenin pathway, including β-catenin, metalloproteniase-7 (MMP-7), T-cell factor-4 (TCF-4), and lymphoid enhancing factor-1 (LEF-1), and increased the protein expression levels of GSK-3β and p-GSK-3β in MDA-MB-231 cells, and the transfection of miR-100 inhibitor in MCF-7 cells showed the opposite effects. In addition, the expression of miR-100 was negatively correlated with the FZD-8 expression in human breast cancer tissues. Overall, these findings suggest that miR-100 suppresses the migration and invasion of breast cancer cells by targeting FZD-8 and inhibiting Wnt/β-catenin signaling pathway and manipulation of miR-100 may provide a promoting therapeutic strategy for cancer breast treatment. [ABSTRACT FROM AUTHOR]

The magnesium(i) complex [(XylNacnac)Mg]2 was employed as a highly efficient catalyst for the cyanosilylation of a variety of ketones with trimethylsilyl cyanide under mild conditions. In contrast to the traditional stoichiometric use of magnesium(i) complexes, 1 provides the first example of a truly catalytic application of Mg(i) complexes. [ABSTRACT FROM AUTHOR]

We present the isolation of the first mononuclear dihalogermylene, and mono- and dinuclear stannylene complexes of transition metals. These exhibit exceptionally pyramidalized Group 14 centers. Additionally, removal of the halide substituents from the Ge/Sn atom was successfully performed in two ways, halide abstraction and reduction, leading to a variety of unusual structural motifs. [ABSTRACT FROM AUTHOR]

Aging is a primary risk factor for neurodegenerative diseases, such as Alzheimer's disease (AD). SIRT2, an NAD+(nicotinamide adenine dinucleotide)-dependent deacetylase, accumulates in the aging brain. Here, we report that, in the amyloid precursor protein (APP)/PS1 transgenic mouse model of AD, genetic deletion of SIRT2 or pharmacological inhibition of SIRT2 ameliorates cognitive impairment. We find that suppression of SIRT2 enhances acetylation of APP, which promotes non-amyloidogenic processing of APP at the cell surface, leading to increased soluble APP-α (sAPPα). We discover that lysines 132 and 134 of the major pathogenic protein β-amyloid (Aβ) precursor are acetylated and that these residues are deacetylated by SIRT2. Strikingly, exogenous expression of wild-type or an acetylation-mimic APP mutant protects cultured primary neurons from Aβ42 challenge. Our study identifies SIRT2-mediated deacetylation of APP on K132 and K134 as a regulated post-translational modification (PTM) and suggests inhibition of SIRT2 as a potential therapeutic strategy for AD. [Display omitted] • SIRT2 interacts with and deacetylates the highly conserved N terminus of APP • SIRT2 inhibition promotes APP non-amyloidogenic processing at the cell surface • Acetylation of APP-K132/134 is neuroprotective in cultured hippocampal neurons • SIRT2 inhibition improves cognitive deficiency in Alzheimer's disease mouse model Bai et al. show that SIRT2, a sirtuin deacetylase, interacts with the high-affinity ligand E1 domain of APP. Inhibition of SIRT2 has beneficial effects in APP/PS1 mice by maintaining acetylation of APP on the K132 and K134 residues, promoting production of neuroprotective sAPPα. [ABSTRACT FROM AUTHOR]

Breast cancer resistance protein (BCRP)/ATP-binding cassette subfamily G member 2 (ABCG2) mediates multidrug resistance (MDR) in breast cancers. In this study, we aimed to investigate the role of microRNAs in regulation of BCRP expression and BCRP-mediated drug resistance in breast cancer cells. Microarray analysis was performed to determine the differential expression patterns of miRNAs that target BCRP between the MX-resistant breast cancer cell line MCF-7/MX and its parental MX-sensitive cell line MCF-7. MiR-181a was found to be the most significantly down-regulated miRNA in MCF-7/MX cells. Luciferase activity assay showed that miR-181a mimics inhibited BCRP expression by targeting the 3′ untranslated region (UTR) of the BCRP mRNA. Overexpression of miR-181a down-regulated BCRP expression, and sensitized MX-resistant MCF-7/MX cells to MX. In a nude mouse xenograft model, intratumoral injection of miR-181a mimics inhibited BCRP expression, and enhanced the antitumor activity of MX. In addition, miR-181a inhibitors up-regulated BCRP expression, and rendered MX-sensitive MCF-7 cells resistant to MX. These findings suggest that miR-181a regulates BCRP expression via binding to the 3′-UTR of BCRP mRNA. MiR-181a is critical for regulation of BCRP-mediated resistance to MX. MiR-181a may be a potential target for preventing and reversing drug resistance in breast cancer. [ABSTRACT FROM AUTHOR]

The reactivity of two β-diketiminate coordinated magnesium(I) dimers, [LMgMgL], L=[(RNCMe)2CH]−, R=C6H3 iPr2-2,6 (DipNacnac−) or mesityl (MesNacnac−), towards a series of isonitriles and nitriles have been examined. Reactions with the isonitriles, RNC: (R= tBu or C6H3Me2-2,6 (Xyl)), led to reductive CC couplings and the formation of [{(DipNacnac)Mg}2{μ-(XylN=C-)2}] and [{(MesNacnac)Mg}2{μ-( tBuN=C-)2}], or a reductive NC cleavage and the generation of the magnesium cyanide complex, [{(DipNacnac)Mg(μ-CN)}3]. Reactions of the magnesium dimers with benzonitrile, PhCN, afforded the CC-coupled products, [(DipNacnac)Mg[μ-{N=C(Ph)-}2]Mg(NCPh)(DipNacnac)], and [{{(MesNacnac)Mg}2[μ-{N=C(Ph)-}2]}2], whereas the reductive CC cleavage of tBuCN gave rise to a mixture of [(DipNacnac)Mg( tBu)(NC tBu)] and [{(DipNacnac)Mg(μ-CN)}3]. In contrast, a combination of net nitrile isomerization and CC coupling processes was involved in the reduction of Me3SiCN, which yielded [{(DipNacnac)Mg}2{μ-(Me3SiN=C-)2}]. All new compounds were crystallographically and spectroscopically characterized. The outcomes of the reported reactions were found to be dependent upon both the steric bulk of the magnesium(I) reagent, and the nature of the isonitrile/nitrile substituent. This combined with a high degree of selectivity for the reactions, indicates that magnesium(I) dimers may find use by organic and organometallic chemists as viable alternatives to currently available reducing agents that are utilized for the reduction of unsaturated organic substrates. [ABSTRACT FROM AUTHOR]

We report an efficient and practical iron-catalyzed hydrogen atom transfer protocol for assembling acetylenic motifs into functional alkenes. Diversities of internal alkynes could be obtained from readily available alkenes and acetylenic sulfones with excellent Markovnikov selectivity. An iron hydride hydrogen atom transfer catalytic cycle was described to clarify the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

Reactions of [Pt(PCy3)2] (Cy = cyclohexyl) with group 12 metal dihalides have afforded the novel metal only Lewis pair (MOLP) complexes, [(Cy3P)2Pt→MX2] (M = Zn or Cd, X = Br or I), or the oxidative addition product, trans-[(Cy3P)2(I)PtHgI]. The zinc complex represents the first MOLP to contain an unsupported Pt→Zn linkage. [ABSTRACT FROM AUTHOR]