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Chiral RhIII catalysts can catalyze the asymmetric [4+1] spiroannulation of O-pivaloyl oximes with α-diazo homophthalimides under redox-neutral and acid/base-neutral conditions, leading to formation of chiral spirocyclic imines as a result of C–H activation and N–O cleavage. The reaction proceeded with high efficiency and features broad substrate scope, mild reaction conditions, and high to excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Desymmetrization of gem‐dimethyl groups en route to the rhodium(III)‐catalyzed enantioselective sp3 C−H amidation is reported. Synthetically important β‐amino alcohol derivatives were accessed in moderate to good yields and high enantioselectivity. The high enantioselectivity is enabled by an appropriate oxime directing group, sterically biased gem‐groups in the C−H substrate, and high reactivity of the amidating reagent. [ABSTRACT FROM AUTHOR]

Desymmetrization of gem‐dimethyl groups en route to the rhodium(III)‐catalyzed enantioselective sp3 C−H amidation is reported. Synthetically important β‐amino alcohol derivatives were accessed in moderate to good yields and high enantioselectivity. The high enantioselectivity is enabled by an appropriate oxime directing group, sterically biased gem‐groups in the C−H substrate, and high reactivity of the amidating reagent. [ABSTRACT FROM AUTHOR]

Mn(I)-Catalyzed synthesis of seven- or eight-membered carbocycles is disclosed via C–H activation of heteroarenes and coupling with alkyne-functionalized 1,3-cyclopentadiones or 1,3-cyclohexadiones. This n to n + 2 (n = 5, 6) ring expansion reaction proceeded via a C–H alkenylation/carbonyl addition/retro-Aldol cascade. Structurally diverse mid-sized carbocycles were constructed via cleavage of both C–H and C–C bonds in a single operation. [ABSTRACT FROM AUTHOR]

Rhodium(iii)-catalyzed mild benzylic α-fluoroalkenylation of 8-methylquinolines with gem-difluorostyrenes has been developed. This reaction occurred via C–H activation and C–F cleavage and is applicable to a wide range of substrates, leading to the synthesis of Z-alkenyl fluorides under mild and redox-neutral conditions with high regio- and stereoselectivity. [ABSTRACT FROM AUTHOR]

Ru(ii)-catalyzed amidation reactions of 8-methylquinolines with azides have been developed. They are the first examples of [(p-cymene)RuCl2]2-catalyzed C(sp3)–H bond intermolecular amidation reactions which give quinolin-8-ylmethanamines under mild reaction conditions in good yields. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A Rh(III)‐catalyzed, transmetalation triggered C—H activation/annulation of 2‐biphenylboronic acids with diazo compounds from β‐keto esters or 1,3‐dicarboxylates has been developed, leading to the synthesis of two kinds of 9,10‐phenanthrenes. Notably, a rhodacyle was synthesized by treating the rhodium catalyst with stoichiometric amounts of 2‐biphenylboronic acids and pyridine, which was further verified to be active for the catalytic system. The reactions proceeded under redox‐neutral and air‐tolerant conditions to produce a series of all‐carbon six‐membered rings with high efficiency. [ABSTRACT FROM AUTHOR]

The alkenylation reactions of 8-methylquinolines with alkynes, catalyzed by [{Cp*RhCl2}2], proceeds efficiently to give 8-allylquinolines in good yields by C(sp3)H bond activation. These reactions are highly regio- and stereoselective. A catalytically competent five-membered rhodacycle has been structurally characterized, thus revealing a key intermediate in the catalytic cycle. [ABSTRACT FROM AUTHOR]

The alkenylation reactions of 8-methylquinolines with alkynes, catalyzed by [{Cp*RhCl2}2], proceeds efficiently to give 8-allylquinolines in good yields by C(sp3)H bond activation. These reactions are highly regio- and stereoselective. A catalytically competent five-membered rhodacycle has been structurally characterized, thus revealing a key intermediate in the catalytic cycle. [ABSTRACT FROM AUTHOR]

Atrazine (ATR), a bio accumulative herbicide is frequently used in agriculture to control unwanted weeds. Due to continuous application, atrazine persists in the environment and causes deleterious impacts including neurotoxicity, hepatotoxicity, and gut microbiota disorders. Therefore, this study for the first time reports the variation in the gut microbiota, induction of process of apoptosis and autophagy in mice induced by ATR. Results indicated that TUNEL-positive hepatocytes suggestive of apoptosis were increased in livers of different experimental mice. Results on metabolic analysis in liver tissues indicated an overall change in seventy-six metabolites particularly Uridine 5′-diphosphate, Propenoylcarnitine and Chinenoside V resulting in generation of energy-related metabolic disorders and imbalance of oxidation/autoxidation status. Results on gut microbiome inquisition showed that ATR changed the richness and diversity of gut microbiota of mice and number of Firmicutes. Moreover, results also revealed that ATR induced apoptosis via disruption of apoptotic (Bax, Bcl2, and Casp3) and autophagy (LC3/Map1lc3a, Beclin 1/Becn1 and P62/Sqstm1) genes. Results of our experimental study confirmed that changes in gut microbiota play a significant role in process of gut immune regulation and inflammation via different metabolites. In conclusion, the findings of our study provide a new idea for the involvement of mechanisms of detoxification in liver and inquisition of gut microbiota plays crucial role in regulation of physiological activities through liver-gut axis to mitigate toxic effects in animals. [Display omitted] • Long-term ATR exposure results gut microbiota disturbances. • ATR exposure affect metabolism pathways change in liver. • ATR exposure induced apoptosis and autophagy in hepatocytes. • Gut microbiota play important role in regulating physiological activities through liver-gut axis. [ABSTRACT FROM AUTHOR]

Reported herein is the rhodium(III)‐catalyzed C−H activation of anilines bearing an N‐isoquinolyl directing group for oxidative [3+2] annulation with four classes of internal alkynes, leading to atroposelective indole synthesis via dynamic kinetic annulation with C‐N reductive elimination constituting the stereo‐determining step. This reaction proceeds under mild conditions with high regio‐ and enantioselectivity and functional group compatibility. [ABSTRACT FROM AUTHOR]

Reported herein is the rhodium(III)‐catalyzed C−H activation of anilines bearing an N‐isoquinolyl directing group for oxidative [3+2] annulation with four classes of internal alkynes, leading to atroposelective indole synthesis via dynamic kinetic annulation with C‐N reductive elimination constituting the stereo‐determining step. This reaction proceeds under mild conditions with high regio‐ and enantioselectivity and functional group compatibility. [ABSTRACT FROM AUTHOR]

Rhodium(III)-catalyzed C–H acylation of heteroarenes has been realized using cyclobutenones as an acylating reagent. This coupling proceeded via integration of C–H activation of heteroarenes and C–C cleavage of cyclobutenones. The reaction features excellent regio/chemoselectivity leading to versatile chalcones with exclusive E-selectivity. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Ru(II)-Catalyzed Amidation Reactions of 8-Methylquinolines with Azides via C(sp3)-H Activation" by Bingxian Liu published in the "Chemical Communications" in 2015.

Main observation and conclusion: Divergent synthesis of useful skeletons has been realized via rhodium(III)‐catalyzed C—H activation of iminopyridinium ylides and coupling with various unsaturated coupling reagents. Isocoumarins and isoquinolones were obtained via cleavage of the C—N or N—N bond in the ylidic directing group, while fluorinated alkenes were delivered with the directing group intact. The reactions occurred with wide substrate scopes and good efficiency under redox‐neutral and air‐tolerant conditions. Representative products exhibit solid‐state fluorescent property and bioactivity of inhibition toward human cancer cells. [ABSTRACT FROM AUTHOR]

Acetyl-L-carnitine (ALC) is an effective substrate for mitochondrial energy metabolism and is known to prevent neurodegeneration and attenuate heavy metal-induced injury. In this study, we investigated the function of ALC in the recovery of mouse spermatogonia cells (GC-1 cells) after heat stress (HS). The cells were randomly divided into three groups: control group, HS group (incubated at 42°C for 90 min), and HS + ALC group (treatment of 150 μM ALC after incubated at 42°C for 90 min). After heat stress, all of the cells were recovered at 37°C for 6 h. In this study, the content of intracellular lactate dehydrogenase (LDH) in the cell supernatant and the malondialdehyde (MDA) levels, catalase (CAT) levels, and total antioxidant capacity (T-AOC) were significantly increased in the HS group compared to the CON group. In addition, the mitochondrial membrane potential (MMP) was markedly decreased, while the apoptosis rate and the expression of apoptosis-related genes (Bcl-2, Bax, and caspase3) were significantly increased in the HS group compared to the CON group. Furthermore, the number of autophagosomes and the expression of autophagy-related genes (Atg5, Beclin1, and LC3II) and protein levels of p62 were increased, but the expression of LAMP1 was decreased in the HS group compared to the CON group. However, treatment with ALC remarkably improved cell survival and decreased cell oxidative stress. It was unexpected that levels of autophagy were markedly increased in the HS + ALC group compared to the HS group. Taken together, our present study evidenced that ALC could alleviate oxidative stress and improve the level of autophagy to accelerate the recovery of GC-1 cells after heat stress. [ABSTRACT FROM AUTHOR]

As a new field, there are still many unknowns and challenges in the study of nanozymes, such as the mechanism of the reaction catalyzed by nanozymes and the precise control of the catalytic activity of nanozymes. We found that Pd@Pt nanoparticles (NPs) have trienzyme mimetic activity, including peroxidase-like, catalase-like, and oxidase-like activity. More importantly, we observed that the catalytic performance can be modulated by DNA. After systematic studies, the potential mechanisms of DNA modulation of nanozymes were through local coordination, van der Waals forces, and hydrophobic forces, constructing an interface modulation in the Pd@Pt NP enzyme-like system. Based on the surface-interface effect between DNA and Pd@Pt NP nanozymes, a colorimetric sensor was constructed for rapid, accurate and selective analysis of Salmonella by using a specific aptamer. After optimization, the limit of detection was calculated to be ∼58 CFU mL−1. These results indicated that the catalytic activity of Pd@Pt NP nanozymes can be modulated by DNA, and the surface-interface effect has potential in the application of analytical assays. [Display omitted] • The trienzyme catalytic mechanisms of bimetallic Pd@Pt nanoparticles were confirmed. • The unique interaction forces of DNA adsorption on the surface of Pd@Pt NPs were found. • It revealed the interaction between DNA and Pd@Pt NPs was weaker than the binding force between DNA and complementary sequences. • DNA/Pd@Pt NPs system to modulate the catalytic activity of Pd@Pt NPs by changing the active sites of the interface was constructed. • A colorimetric sensor was constructed, which can achieve rapid, accurate, and selective analysis for Salmonella. [ABSTRACT FROM AUTHOR]

Butachlor being an important member of chloroacetanilide herbicides, is frequently used in agriculture to control unwanted weeds. Exposure to butachlor can induce cancer, human lymphocyte aberration, and immunotoxic effects in animals. The current experimental trial was executed to determine the potential risks of herbicide butachlor to immunotoxicity and its mechanism of adverse effects on the spleen. For this purpose, mice were exposed to 8 mg/kg butachlor for 28 days, and the toxicity of butachlor on the spleen of mice was evaluated. We found that butachlor exposure led to an increase in serum ALB, GLU, TC, TG, and TP and changes in the morphological structure of the spleen of mice. More importantly, results showed that butachlor significantly increased the expression level of ATG-5, decreased the protein expression of LC3B and M-TOR, and significantly decreased the mRNA content of M-TOR and p62. Results revealed that the mRNA contents of APAF-1, CYTC, and CASP-9 related genes were significantly decreased after butachlor treatment. Subsequently, the mRNA levels of inflammatory cytokines (IL-1β, TNF-α, IL-10) were reduced in the spleen of treated mice. This study suggested that butachlor induce spleen toxicity and activate the immune response of spleen tissue by targeting the CYTC/BCL2/M-TOR pathway and caspase cascading activation of spleen autophagy and apoptosis pathways which may ultimately lead to immune system disorders. • Exposure to the butachlor has the potential risks to immunotoxicity. • Butachlor exposure induced apoptosis and autophagy in spleen. • CYTC/Bcl-2/mTOR pathway and caspase cascading activation target cell death. • Butachlor induce spleen toxicity and activate the immune response. [ABSTRACT FROM AUTHOR]

Butachlor is a systemic herbicide widely applied on wheat, rice, beans, and different other crops, and is frequently detected in groundwater, surface water, and soil. Therefore, it is necessary to investigate the potential adverse health risks and the underlying mechanisms of hepatotoxicity caused by exposure to butachlor in invertebrates, other nontarget animals, and public health. For this reason, a total of 20 mice were obtained and randomly divided into two groups. The experimental mice in one group were exposed to butachlor (8 mg/kg) and the mice in control group received normal saline. The liver tissues were obtained from each mice at day 21 of the trial. Results indicated that exposure to butachlor induced hepatotoxicity in terms of swelling of hepatocyte, disorders in the arrangement of hepatic cells, increased concentrations of different serum enzymes such as alkaline phosphate (ALP) and aspartate aminotransferase (AST). The results on the mechanisms of liver toxicity indicated that butachlor induced overexpression of Apaf-1, Bax, Caspase-3, Caspase-9, Cyt-c, p53, Beclin-1, ATG-5, and LC3, whereas decreases the expression of Bcl-2 and p62 suggesting abnormal processes of apoptosis and autophagy. Results on different metabolites (61 differential metabolites) revealed upregulation of PE and LysoPC, whereas downregulation of SM caused by butachlor exposure in mice led to the disruption of glycerophospholipids and lipid metabolism in the liver. The results of our experimental research indicated that butachlor induces hepatotoxic effects through disruption of lipid metabolism, abnormal mechanisms of autophagy, and apoptosis that provides new insights into the elucidation of the mechanisms of hepatotoxicity in mice induced by butachlor. [Display omitted] • Exposure to the herbicide butachlor results in hepatotoxicity. • Butachlor exposure induced apoptosis and autophagy in hepatocytes. • Butachlor significantly altered the variation of 61 metabolites and disturbed lipid metabolism. • PE and LysoPC disturbed the glycerophospholipid metabolism under butachlor exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exposure to the Zearalenone results in hepatotoxicity, which altered liver function and damage liver structure. • Zearalenone exposure induced apoptosis and autophagy in hepatocytes via mitochondrial apoptosis and Beclin1 autophagy signaling pathway. • Zearalenone significantly altered the variation of 91 metabolites, which mainly involved in glycerophospholipid metabolism pathway. • Zearalenone affect the liver via interaction of gut microbiome and metabolites. Zearalenone (ZEN), a mycotoxin is frequently detected in different food products and has been widely studied for its toxicity. However, the underlying mechanisms of hepatotoxic effects, relationship between gut microbiome and liver metabolite mediated hepatotoxicity mechanisms induced by ZEN are still not clear. Here, we reported that the different microscopic changes like swelling of hepatocyte, disorganization of hepatocytes and extensive vacuolar degeneration were observed, and the mitochondrial functions decreased in exposed mice. Results exhibited up-regulation in expression of signals of apoptosis and autophagy in liver of treated mice via mitochondrial apoptotic and autophagy pathway (Beclin1/p62). The diversity of gut microbiome decreased and the values of various microbiome altered in treated mice, including 5 phyla (Chloroflexi, Sva0485, Methylomirabilota, MBNT15 and Kryptonia) and genera (Frankia, Lactococcus, Anaerolinea, Halomonas and Sh765B-TzT-35) significantly changed. Liver metabolism showed that the concentrations of 91 metabolite including lipids and lipid like molecules were significantly changed. The values of phosphatidylcholine, 2-Lysophosphatidylcholine and phosphatidate concentrations suggestive of abnormal glycerophosphate metabolism pathway were significantly increased in mice due to exposure to ZEN. In conclusion, the findings suggest that the disorders in gut microbiome and liver metabolites due to exposure to ZEN in mice may affect the liver. [ABSTRACT FROM AUTHOR]

Fluorine (F) and its compounds produced from industrial production and coal combustion can cause air, water and soil contamination, which can accumulate in animals, plants and humans via food chain threatening public health. Fluoride exposure affects liver, kidney, gastrointestinal and reproductive system in humans and animals. Literature regarding fluoride influence on intestinal structure and microbiota composition in ducks is scarce. This study was designed to investigate these effects by using simple and electron microscopy and 16S rRNA sequencing techniques. Results indicated an impaired structure with reduced relative distribution of goblet cells in the fluoride exposed group. Moreover, the gut microbiota showed a significant decrease in alpha diversity. Proteobacteria , Firmicutes and Bacteroidetes were the most abundant phyla in both control and fluoride-exposed groups. Specifically, fluoride exposure resulted in a significant decrease in the relative abundance of 9 bacterial phyla and 15 bacterial genera. Among them, 4 phyla (Latescibacteria , Dependentiae , Zixibacteria and Fibrobacteres) and 4 genera (Thauera , Hydrogenophaga , Reyranella and Arenimonas) weren't even detectable in the gut microbiota of the ducks. In summary, higher fluoride exposure can significantly damage the intestinal structure and gut microbial composition in ducks. • Intestinal structure and gut microbial composition and diversity depends on various animal and environment related factors. • Fluoride and its compounds can accumulate in animals and plants and threaten public health through the food chain. • Simple and electron microscopy coupled with 16S rRNA sequencing revealed that excessive fluoride exposure can significantly impair the intestinal structure and the gut microbial diversity and composition in ducks. [ABSTRACT FROM AUTHOR]