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Simple and commercially available magnesium halides catalyzed the hydroboration of various isocyanates and ketones.

A highly tunable defluorophosphorylation of fluorinated peroxides for the preparation of C3,4-diphosphoryl furans and C4-monophosphoryl furans under conditions with no added transition metals is disclosed.

The emerging potassium-ion batteries (PIBs) have been placing stratospheric expectations for realizing grid-scale electrochemical storage of renewable energy. However, the unsatisfactory K-storage of PIB anode materials, especially promising carbonaceous materials, significantly limited the development of PIBs. Here, a molecular design strategy was proposed to realize controllable structure transformation of soft carbon (SC) materials for enhanced K-storage performance. The optimized SC-PCN material delivered a high reversible K-storage capacity of 838 mAh/g at 50 mA/g, outstanding rate capability (213 mAh/g at 1000 mA/g), and excellent long-term cycling performance (301 mAh/g maintained after 300 cycles at 500 mA/g), superior to most previously reported carbon-based PIB anodes materials. Reaction kinetic analysis revealed that the proposed molecular design strategy can achieve the transformation from a surface capacitive-dominated mechanism to a capacitive-diffusion hybrid mechanism for SC-PCN, benefiting from its unique microstructures with highly defective surface generated via the synergistic effect from template removal, N doping, and surface reconstruction. The optimal hybrid K-storage mechanism should be responsible for the excellent K-storage properties of the prepared SC-PCN.

The direct cross-couplings of diaryl sulfoxides with aryl bromides via C-S bond cleavage could be readily accomplished using nickel(II) as the catalyst, 1,2-bis(diphenylphosphino)ethane (dppe) as the ligand, and magnesium turnings as the reducing metal in THF, leading to the corresponding biaryls in moderate to good yields. The reaction exhibited a broad substrate scope and could be applied to a gram-scale synthesis. The "one-pot" reaction, which avoids the utility of presynthesized and moisture-labile organometallic compounds, is operationally simple and step-economic.

The efficient palladium-catalyzed synthesis of esters from readily available arenes has been developed. These C-H bond esterifications were achieved relying on the regioselective thianthrenation to generate the aryl-TT salts, which were treated as reactive electrophilic substrates to couple with phenol formate and

Oncogenic stress induces DNA damage repair (DDR) that permits escape from mitotic catastrophe and allows early precursor lesions during the evolution of cancer. SAMHD1, a dNTPase protecting cells from viral infections, has been recently found to participate in DNA damage repair process. However, its role in tumorigenesis remains largely unknown. Here, we show that SAMHD1 is up-regulated in early-stage human carcinoma tissues and cell lines under oxidative stress or genotoxic insults. We further demonstrate that de-ubiquitinating enzyme USP7 interacts with SAMHD1 and de-ubiquitinates it at lysine 421, thus stabilizing SAMHD1 protein expression for further interaction with CtIP for DDR, which promotes tumor cell survival under genotoxic stress. Furthermore, SAMHD1 levels positively correlates with USP7 in various human carcinomas, and is associated with an unfavorable survival outcome in patients who underwent chemotherapy. Moreover, USP7 inhibitor sensitizes tumor cells to chemotherapeutic agents by decreasing SAMHD1 in vitro and in vivo. These findings suggest that de-ubiquitination of SAMHD1 by USP7 promotes DDR to overcome oncogenic stress and affect chemotherapy sensitivity.

Diverse 2,3-substituted indanones are accessed in an efficient and robust protocol by a rhodium-catalyzed tandem carborhodium/cyclization and intramolecular proton shift pathway. The reaction is compatible with a broad range of functional internal acetylenes, especially for natural and functionalized alkynes derivatives, affording the desired indanones in good to excellent yields. Remarkably, this reaction features very mild and sustainable conditions using water as the sole solvent and without exogenous ligands. Control studies support that indanone is formed through the intramolecular proton transfer process from the key intermediate indenol.

We report a general, scalable, and convenient photochemical process for diversities of distal oxygenated nitriles from corresponding less-strained ketoxime esters allowing one-step introductions of ether and cyano groups, which avoids the utilization of toxic cyanide reagents. A wide range of ketoxime esters involving five-membered to eight-membered cycloketoxime esters and linear ketoxime esters participate smoothly under operately simple and mild conditions, affording structurally variable ring-opening products.

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 was developed.

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

A copper-catalysed three-component reaction utilizing readily available feedstocks was investigated, providing an operationally simple and practical route to trifluoromethyl allenes under mild and environmentally friendly conditions.

A practical and convenient approach that enabled radical-mediated conjugate addition of unreactive alkenes to electron-deficient alkenes leading to a broad range of substituted malononitriles was disclosed.

An efficient defluorinative net-[3 + 3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was developed. The present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination, defluorination, and annulation. The desired pyrimidines could be obtained with good functional group tolerance and moderate to good yields. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative annulation. The pendant π system would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp3)–F bond.

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 simple, commercially available ZnBr2 has been successfully employed as a highly efficient and chemoselective catalyst for the dehydrogenative borylation of terminal alkynes with HBpin under mild conditions. It shows a good tolerance toward various functional groups such as aryl, alkyl, heteroaryl, etc. The plausible reaction mechanism has been investigated based on the corresponding stoichiometric experiments and DFT calculations.

An extremely facile and up-scalable approach has been proposed to disperse ferric grains onto bacterial cellulose (BC) nanofibers. The BC-induced hydrolytic deposition can be performed at room temperature without using any organic solvents, toxic reagents, or complicated apparatuses, enabling a green pathway in realizing industrialization. After carbonization, the randomly oriented carbonized BC (CBC) nanofibers transmit the electrons throughout the electrode, while the inherited reticular morphology boosts the thorough penetration of electrolyte. Moreover, the sufficient space created by interconnected CBC nanofibers is able to accommodate the volume change of the nanosized Fe3O4 active materials during repeated Li+ intercalation and deintercalation. As a result, the as-prepared Fe3O4/CBC composites deliver the superior electrochemical performance as the free-standing anodes in Li-ion batteries (LIBs), including the impressive reversible capacity of 702 mAh g−1 after 400 cycles at 400 mA g−1, decent rate capability with capacity of 437 mAh g−1 at 2000 mA g−1, and a long cycling lifespan up to 1000 cycles at 800 mA g−1. This work provides a scalable and green approach to fabricate high-performance LIBs anode with the natural sustainable biomass.

A nickel-catalyzed direct reductive cross-coupling of disubstituted cycloalkyl iodides with aryl iodides was developed. The one-pot reaction, which is simple to operate, was capable of proceeding efficiently in a stereocontrolled manner to afford a variety of cross-coupled products with high diastereoselectivity and wide functional group tolerance.

Progerin, a product of LMNA mutation, leads to multiple nuclear abnormalities in patients with Hutchinson-Gilford progeria syndrome (HGPS), a devastating premature aging disorder. Progerin also accumulates during physiological aging. Here, we demonstrate that impaired insulin-like growth factor 1 receptor (IGF-1R)/Akt signaling pathway results in severe growth retardation and premature aging in Zmpste24 −/− mice, a mouse model of progeria. Mechanistically, progerin mislocalizes outside of the nucleus, interacts with the IGF-1R, and down-regulates its expression, leading to inhibited mitochondrial respiration, retarded cell growth, and accelerated cellular senescence. Pharmacological treatment with the PTEN (phosphatase and tensin homolog deleted on chromosome 10) inhibitor bpV (HOpic) increases Akt activity and improves multiple abnormalities in Zmpste24-deficient mice. These findings provide previously unidentified insights into the role of progerin in regulating the IGF-1R/Akt signaling in HGPS and might be useful for treating LMNA -associated progeroid disorders.

An efficient Sonogashira coupling of a heterocyclic phosphonium salt with a terminal alkyne via C-P bond cleavage was developed. The reactions proceeded smoothly in the presence of palladium catalyst, copper(I) iodide, and

Functional molecules bearing polychlorinated moieties usually play versatile roles in organic synthesis and biochemistry. A copper-catalyzed multicomponent polychloro-carboalkynylation of alkenes presents an efficient and operationally simple approach for the synthesis of β-polychlorinated alkynes. Mechanistic experiments were conducted demonstrating that an

We have developed a modular, convenient and practical copper-catalyzed platform for the preparation of alkene nitriles from corresponding cycloketoxime esters via radical-mediated C–C bond cleavage. A broad scope of cycloketoxime esters (4-membered to 8-membered) and some complex substrates derived from natural product derivatives performed well, affording corresponding ring opening products in the presence of copper salts. Moreover, the etherification, oxidation and alkynylation of cycloketoxime esters could also be achieved under variable copper-catalyzed conditions.

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.

It is attractive to establish an efficient and practical platform affording functional compounds using readily available feedstocks as starting materials under mild conditions. We describe a direct copper-catalyzed fluorocarboalkynylation of the readily available alkynes with excellent regio- and stereoselectivity. A wide range of conjugated trifluoromethyl 1,3-enynes were obtained in good yields by this operationally simple strategy. The mechanistic experiments and DFT calculation revealed that a radical-mediated process was involved in the catalytic cycle.

Correction for ‘Copper-catalysed synthesis of trifluoromethyl allenes via fluoro-carboalkynylation of alkenes’ by Mengning Wang et al., Org. Chem. Front., 2022, 9, 1844–1849, https://doi.org/10.1039/D1QO01823J.

Septin4 is a tumor suppressor protein that promotes cell programmed death in various cell types through specifically antagonizing XIAP (X linked inhibitor of apoptosis), little is known its other novel binding partner and role in colorectal cancer. In this study, we found that Septin4 significantly expressed lower in human colon cancer when compared to peri-tumor benign cells, and its low expression was significantly associated with worse prognostic outcomes. Furthermore, Septin4 participated in DOX-induced colon cancer cell death in vitro. Septin4-overexpressing colon cancer cells displayed augmented apoptotic cell death and ROS production. Additionally, Septin4-knockdown cells revealed a resistance of DOX-induced cell death and reduced ROS production. Importantly, we first identified that BAX is a novel Septin4 binding partner and the interaction is enhanced under DOX treatment. Finally, Septin4-knockdown promoted colon cells growth in vivo. These observations suggest that Septin4 as an essential molecule contribute to the occurrence and development of human colon cancer and provide new technical approaches for targeted treatment of this disease.

Hydroboration, namely the direct addition of B-H bonds across C=O, C=N, C=C, C≡C and C≡N etc ., unsaturated bonds, is one of important methods for preparing organoborane compounds. Recently, the alkaline earth metal complexes have been widely employed as efficient catalysts for the hydroboration reaction. This article summarizes recent advancements in the alkaline earth metal (especially magnesium) catalyzed hydroboration of unsaturated organic compounds such as aldehydes, ketones, esters, amines, pyridines, nitriles, alkenes, alkynes, carbonates.

A series of asymmetrical β-diketiminate ligand stabilized magnesium(I) complexes have been successfully synthesized and structurally characterized via single crystal X-ray diffraction. When they were employed as efficient catalysts in the hydroboration of aryl, alkyl and alicyl epoxides with pinacolborane (HBpin), the resultant borate ester products were obtained with high yields and high regioselectivities. The results also revealed that they showed a marked preference for the branched Markovnikov hydroborated products instead of the linear anti-Markovnikov borate esters which are typically formed in protocols involving transition metal catalysts. The preliminary hydroboration reaction mechanism has been investigated via the corresponding DFT calculation.

The simple, commercially available ZnBr

A titanium(IV)-mediated ring-opening/dehydroxylative cross-coupling of diaryl-substituted methanols with a cyclopropanol derivative was developed. The reactions proceeded efficiently to provide synthetically useful γ,γ-diaryl esters in moderate to good yields, which could be applied to the functionalization of complex molecules derived from bioactive fenofibrate and isoxepac and the synthesis of a precursor of Zoloft.