Aliphatic trifluoromethyl ketones are a type of unique fluorine-containing subunit which plays a significant role in altering the physical and biological properties of molecules. However, catalytic ...methods to provide direct access to aliphatic trifluoromethyl ketones is highly desirable yet remains underdeveloped, partially due to the high reactivity and instability of trifluoroacetyl radical. Herein, we report a photocatalytic synthesis of trifluoromethyl ketones from alkyl bromides with trifluoroacetic anhydride. The reaction features a dual catalysis of visible-light and XAT reaction, followed by an enabling radical-radical cross-coupling of alkyl radical with a stabilized trifluoromethyl radical. The reaction provides the first straightforward access to aliphatic trifluoromethyl ketones from easily-available and cost-effective alkyl halides and TFAA.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Three‐membered cyclic structures are widely existing in natural products and serve as enabling intermediates in organic synthesis. However, the efficient and straightforward access to such structures ...with diversity remains a formidable challenge. Herein, a general and practical protocol to aziridines and cyclopropanes synthesis using free XH2 (X=C or N) with alkenes by thianthrenation is presented. This metal‐free protocol features the direct aziridination and cyclopropanation with unprotected XH2. Free sulfonamides, amides, carbamates, amines, and methylene with acidic protons, are good precursors, providing an attractive alternative for straightforward synthesis of aziridines and cyclopropanes from easily available starting materials.
Herein, a general and practical protocol to aziridines and cyclopropanes using free XH2 (X=C or N) with alkenes by thianthrenation is presented under mild conditions. Free sulfonamides, amides, carbamates, amines, and acidic methylene with protons, are good precursors for three‐membered ring formation, providing an attractive alternative for straightforward synthesis of aziridines and cyclopropanes from easily available starting materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Selective functionalization of allylic C-H bonds into other chemical bonds is among the most straightforward and attractive, yet challenging transformations. Herein, a transition-metal-free protocol ...for direct allylic C-H nitrogenation, oxygenation, and carbonation of alkenes by thianthrenation was developed. This operationally simple protocol allows for the unified allylic C-H amination, esterification, etherification, and arylation of vinyl thianthrenium salts. Notably, the reaction furnishes multialkyl substituted allylic amines, ammonium salts, sulfonyl amides, esters, and ethers in good yields. The reaction proceeds under mild conditions with excellent functional group tolerance and could be applied to late-stage allylation of natural products, drug molecules and peptides with excellent chemoselectivity.
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IJS, KILJ, NUK, UL, UM, UPUK
Tumor recurrence following treatment remains a major clinical challenge. Evidence from xenograft models and human trials indicates selective enrichment of cancer-initiating cells (CICs) in tumors ...that survive therapy. Together with recent reports showing that CIC gene signatures influence patient survival, these studies predict that targeting self-renewal, the key 'stemness' property unique to CICs, may represent a new paradigm in cancer therapy. Here we demonstrate that tumor formation and, more specifically, human colorectal CIC function are dependent on the canonical self-renewal regulator BMI-1. Downregulation of BMI-1 inhibits the ability of colorectal CICs to self-renew, resulting in the abrogation of their tumorigenic potential. Treatment of primary colorectal cancer xenografts with a small-molecule BMI-1 inhibitor resulted in colorectal CIC loss with long-term and irreversible impairment of tumor growth. Targeting the BMI-1-related self-renewal machinery provides the basis for a new therapeutic approach in the treatment of colorectal cancer.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Acute myocardial infarction refers to a sudden death of cardiomyocytes, which leads to a large mortality worldwide. To attenuate acute myocardial infarction, strategies should be made to increase ...cardiomyocyte survival, improve postinfarcted cardiac function, and reverse the process of cardiac remodeling. Autophagy, a pivotal cellular response, has been widely studied and is known to be involved in various kinds of diseases. In the recent few years, the role of autophagy in diseases has been drawn increasing attention to by researchers. Here in this review, we mainly focus on the discussion of the effect of autophagy on the pathogenesis and progression of acute myocardial infarction under ischemic and ischemia/reperfusion injuries. Furthermore, several popular therapeutic agents and strategies taking advantage of autophagy will be described.
Direct and site-selective C-H functionalization of alkenes under environmentally benign conditions represents a useful and attractive yet challenging transformation to access value-added molecules. ...Herein, a unified protocol for a variety of intermolecular Heck-type functionalizations of C
-H bond of alkenes has been developed by thianthrenation. The reaction features metal-free and operationally simple conditions for exclusive cine-selective C-H functionalization of aliphatic and aryl alkenes to forge C-C, C-N, C-P, and C-S bonds at room temperature, providing a general protocol for intermolecular Heck-type reaction of alkenes with nucleophiles (Nu = sulfinates, cyanides, amines, amides). Alkenes undergo cine-sulfonylation, cyanation, amination to afford alkenyl sulfones, alkenyl nitriles and enamines.
Three new phenylphosphonate (PhPO3) and salicylate (Sal) substituted heterometallic titanium-oxo clusters (ST-M), namely Ti6Mn2O4(OEt)4(PhPO3)2(Sal)6(EtOH)2 (ST-Mn), ...Ti6Zn2O4(OEt)4(PhPO3)2(Sal)6(EtOH)2(H2O)2 (ST-Zn) and Ti6Tb2O4(OiPr)4(PhPO3)2(Sal)6Cl2(iPrOH)2·iPrOH (ST-Tb), were synthesized. The most impressive structural feature of these compounds is the calixarene-type carboxylate endpoint in the Ti6-oxo core, which can readily capture metal ions with different radii and coordination geometries, for example, Mn2+, Zn2+ and Tb3+ ions in this case, to generate neutral mixed-metal Ti6M2-oxo clusters. Flower-like ST-Mn (denoted as FST-Mn) nanocrystals formed by nanosheets can be facilely obtained in gram-scale quantities from a simple solution reaction using Triton X-100 as a conditioning agent. The catalytic activity of these materials was evaluated by photocatalytic degradation of rhodamine B (RhB), among which FST-Mn showed the highest catalytic activity. Under visible light, 93.0% of RhB (50 ppm, 100 mL) was decomposed within 30 min catalyzed by FST-Mn without adding hydrogen peroxide, which is quite preeminent among Ti based catalysts. The catalytic decomposition efficiency under the same experimental conditions was 80.0% for ST-Mn, 24.6% for ST-Zn and 17.6% for ST-Tb. Investigation of the degradation mechanism showed that h+ and ·OH were the dominant active species in the decomposition of RhB. Moreover, the reusability and stability of FST-Mn were also verified.
An electrooxidative direct difunctionalization of internal alkynes with sulfonyl hydrazides has been developed for the construction of sulfonated enethers. In this transformation, metal catalysts or ...stoichiometric amount of oxidants are not required and molecular nitrogen and hydrogen are the sole byproducts, providing a simple and green approach for preparing various sulfonyl tetrasubstituted alkenes. Notably, the protocol could be efficiently scaled up and the follow-up procedures of the corresponding functionalized alkenes demonstrate the practicality of the electrochemical synthesis.
An electrooxidative direct difunctionalization of internal alkynes with sulfonyl hydrazides has been developed for the construction of sulfonated enethers.
Traditional coupling of ligands for gold wet etching makes large-scale applications problematic. Deep eutectic solvents (DESs) are a new class of environment-friendly solvents, which could possibly ...overcome the shortcomings. In this work, the effect of water content on the Au anodic process in DES ethaline was investigated by combining linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). Meanwhile, we employed atomic force microscopy (AFM) to image the evolution of the surface morphology of the Au electrode during its dissolution and passivation process. The obtained AFM data help to explain the observations about the effect of water content on the Au anodic process from the microscopic perspective. High water contents make the occurrence of anodic dissolution of gold at higher potential, but enhances the rate of the electron transfer and gold dissolution. AFM results reveal the occurrence of massive exfoliation, which confirms that the gold dissolution reaction is more violent in ethaline with higher water contents. In addition, AFM results illustrate that the passive film and its average roughness could be tailored by changing the water content of ethaline.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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