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1.
Hum Mol Genet ; 32(8): 1334-1347, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36383401

RESUMO

More than 250 million people in the world are chronically infected with hepatitis B virus (HBV), which causes serious complications. Host genetic susceptibility is essential for chronic hepatitis B (CHB), and our previous genome-wide association study identified a single-nucleotide polymorphism (SNP), rs1883832, in the 5' untranslated region of CD40 predisposing to chronic HBV infection, but the underlying mechanism remains undefined. This study aimed to investigate whether rs1883832 was the real functional SNP (fSNP) of CD40 and how it modulated HBV clearance in hepatocytes. We determined the fSNP of CD40 and its regulatory protein(s) using luciferase reporter assays, electrophoretic mobility shift assay, flanking restriction enhanced pulldown and chromatin immunoprecipitation. The potential anti-HBV activity of CD40 and its downstream molecule BST2 was assessed in HBV-transfected and HBV-infected hepatoma cells and HBV-infected primary human hepatocytes. Moreover, the mechanism of CD40 was investigated by mRNA sequencing, quantitative real-time polymerase chain reaction, immunofluorescence and western blot. We revealed rs1883832 as the true fSNP of CD40 and identified ANXA2 as a negative regulatory protein that preferentially bound to the risk allele T of rs1883832 and hence reduced CD40 expression. Furthermore, CD40 suppressed HBV replication and transcription in hepatocytes via activating the JAK-STAT pathway. BST2 was identified to be the key IFN-stimulated gene regulated by CD40 after activating JAK-STAT pathway. Inhibition of JAK/STAT/BST2 axis attenuated CD40-induced antiviral effect. In conclusion, a functional variant of CD40 modulates HBV clearance via regulation of the ANXA2/CD40/BST2 axis, which may shed new light on HBV personalized therapy.


Assuntos
Anexina A2 , Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B/genética , Janus Quinases/metabolismo , Estudo de Associação Genômica Ampla , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Hepatócitos/metabolismo , Hepatite B Crônica/genética , Hepatite B Crônica/metabolismo , Fatores de Transcrição/genética , Hepatite B/metabolismo , Antígenos CD/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Proteínas Ligadas por GPI/farmacologia , Anexina A2/genética
2.
Microb Pathog ; 189: 106597, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395316

RESUMO

Vibrio anguillarum is one of the major pathogens responsible for bacterial infections in marine environments, causing significant impacts on the aquaculture industry. The misuse of antibiotics leads to bacteria developing multiple drug resistances, which is detrimental to the development of the fisheries industry. In contrast, live attenuated vaccines are gradually gaining acceptance and widespread recognition. In this study, we constructed a double-knockout attenuated strain, V. anguillarum ΔspeA-aroC, to assess its potential for preparing a live attenuated vaccine. The research results indicate a significant downregulation of virulence-related genes, including Type VI secretion system, Type II secretion system, biofilm synthesis, iron uptake system, and other related genes, in the mutant strain. Furthermore, the strain lacking the genes exhibited a 67.47% reduction in biofilm formation ability and increased sensitivity to antibiotics. The mutant strain exhibited significantly reduced capability in evading host immune system defenses and causing in vivo infections in spotted sea bass (Lateolabrax maculatus), with an LD50 that was 13.93 times higher than that of the wild-type V. anguillarum. Additionally, RT-qPCR analysis of immune-related gene expression in spotted sea bass head kidney and spleen showed a weakened immune response triggered by the knockout strain. Compared to the wild-type V. anguillarum, the mutant strain caused reduced levels of tissue damage. The results demonstrate that the deletion of speA and aroC significantly reduces the biosynthesis of biofilms in V. anguillarum, leading to a decrease in its pathogenicity. This suggests a crucial role of biofilms in the survival and invasive capabilities of V. anguillarum.


Assuntos
Bass , Doenças dos Peixes , Vibrioses , Vibrio , Animais , Vibrioses/microbiologia , Bass/microbiologia , Virulência/genética , Vibrio/genética , Antibacterianos , Doenças dos Peixes/microbiologia
3.
J Infect Dis ; 228(6): 694-703, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36932045

RESUMO

BACKGROUND: Alpha kinase 1 (ALPK1) agonist has recently been reported to demonstrate anti-hepatitis B virus (HBV) efficacy via activating NF-κB signaling, which is crucial for maximizing interferon (IFN) responses. Here, we investigated the impact of ALPK1 on HBV replication and explored ALPK1 variants for predicting the response to pegylated IFN-α (PegIFN-α) treatment. METHODS: The potential anti-HBV effect of ALPK1 was evaluated in HBV-integrated and HBV-infected hepatoma cells. The potentially functional genetic variants of ALPK1 were screened out, and their correlations with PegIFN-α treatment response were assessed in 945 hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B (CHB). RESULTS: We revealed that ALPK1 inhibited HBV replication in hepatocytes via activating the JAK-STAT pathway. ALPK1 overexpression improved the anti-HBV effect of IFN-α in cell models. A missense variant, rs35389530 (P660L), of ALPK1 was strongly associated with combined response (CR; namely, HBeAg seroconversion and HBV DNA level <3.3log10 IU/mL) to PegIFN-α treatment in patients with CHB (P = 2.12 × 10-6). Moreover, a polygenic score integrating ALPK1_rs35389530 and 2 additional genetic variants was further significantly associated with CR (Ptrend = 9.28 × 10-7), hepatitis B surface antigen (HBsAg) level (Ptrend = .0002), and HBsAg loss (Ptrend = .025). CONCLUSIONS: The anti-HBV effects of ALPK1 through activating JAK-STAT pathway provides a new perspective for CHB therapy. ALPK1_rs35389530 and polygenic score are potential biomarkers to predict PegIFN-α treatment response and may be used for optimizing CHB treatment.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Vírus da Hepatite B/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B/uso terapêutico , Antígenos E da Hepatite B , Janus Quinases/uso terapêutico , Fatores de Transcrição STAT/uso terapêutico , Transdução de Sinais , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , DNA Viral , Polietilenoglicóis/uso terapêutico , Replicação Viral , Resultado do Tratamento
4.
Appl Microbiol Biotechnol ; 106(7): 2403-2414, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35352152

RESUMO

Water-oil interface of bacterial cell-stabilized Pickering emulsions is an exceptional habitat for microbial assimilation of both hydrophobic nutrients solubilized in oil phase and hydrophilic ones solubilized in water phase. Crystal substrate inhibition, i.e., decreasing phytosterol degradation with the increase loading of crystal phytosterols, is always observed during microbial transformation of phytosterols into steroid synthons in Mycolicibacterium sp (China Center of Industrial Culture Collection, CICC 21,097) cell-stabilized Pickering emulsions. In the present work, we confirmed that crystal substrate inhibition was attributed to the interaction between M. neoaurum and phytosterol crystals that led to the detachment of bacterial cells from the oil-water interfaces in bacterial cell-stabilized Pickering emulsions. Under the selected operation condition (25 ml BEHP per 40 ml water, 60 g/L glucose, 25 g/L phytosterols), the product androst-4-ene-3, 17-dione (AD) and androsta-1, 4-dien-3, 17-dione (ADD) concentration increased linearly with the progress of microbial transformation and reached almost 6 g/L at the 11th day. This is a paradigm for microbial transformation of crystal substrates as well as in the presence of other surface active additives (such as chitosan and nonionic surfactants) in bacterial cell-stabilized Pickering emulsions. KEY POINTS: • Microbial transformation of crystal phytosterols in Pickering emulsions • Crystal substrate inhibition occurring during microbial transformation • Interaction between phytosterol crystals and bacterial cells leading to demulsification.


Assuntos
Quitosana , Fitosteróis , Quitosana/química , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Fitosteróis/metabolismo , Água/química
5.
Org Biomol Chem ; 18(5): 956-963, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31930235

RESUMO

A Brønsted acid/visible-light-promoted Markovnikov hydroamination of vinylarenes with arylamines in the presence of TPT and CF3CO2H has been developed. This transformation provides a green approach to alpha-amino-substituted arylalkanes under metal-free conditions.

6.
Neurochem Res ; 42(11): 3233-3244, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28758176

RESUMO

Preliminary studies conducted in our laboratory have confirmed that Bacopaside I (BS-I), a saponin compound isolated from Bacopa monnieri, displayed antidepressant-like activity in the mouse behavioral despair model. The present investigation aimed to verify the antidepressant-like action of BS-I using a mouse model of behavioral deficits induced by chronic unpredictable mild stress (CUMS) and further probe its underlying mechanism of action. Mice were exposed to CUMS for a period of 5 consecutive weeks to induce depression-like behavior. Then, oral gavage administrations with vehicle (model group), fluoxetine (12 mg/kg, positive group) or BS-I (5, 15, 45 mg/kg, treated group) once daily were started during the last two weeks of CUMS procedure. The results showed that BS-I significantly ameliorated CUMS-induced depression-like behaviors in mice, as characterized by an elevated sucrose consumption in the sucrose preference test and reduced immobility time without affecting spontaneous locomotor activity in the forced swimming test, tail suspension test and open field test. It was also found that BS-I treatment reversed the increased level of plasma corticosterone and decreased mRNA and protein expressions of glucocorticoid receptor induced by CUMS exposure, indicating that hypothalamic-pituitary-adrenal (HPA) axis hyperactivity of CUMS-exposed mice was restored by BS-I treatment. Furthermore, chronic administration of BS-I elevated expression levels of brain-derived neurotrophic factor (BDNF) (mRNA and protein) and activated the phosphorylation of extracellular signal-regulated kinase and cAMP response element-binding protein in the hippocampus and prefrontal cortex in mice subjected to CUMS procedure. Taken together, these results indicated that BS-I exhibited an obvious antidepressant-like effect in mouse model of CUMS-induced depression that was mediated, at least in part, by modulating HPA hyperactivity and activating BDNF signaling pathway.


Assuntos
Antidepressivos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Saponinas/uso terapêutico , Estresse Psicológico/metabolismo , Triterpenos/uso terapêutico , Animais , Antidepressivos/farmacologia , Doença Crônica , Depressão/tratamento farmacológico , Depressão/psicologia , Relação Dose-Resposta a Droga , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/psicologia , Resultado do Tratamento , Triterpenos/farmacologia
7.
Yao Xue Xue Bao ; 51(6): 843-52, 2016 06.
Artigo em Zh | MEDLINE | ID: mdl-29878736

RESUMO

The international cooperated research projects of the Human Microbiome Project (HMP) and Metagenomics of The Human Intestinal Tract (MetaHIT) were officially launched in 2007, which indicated the era of metagenomics research of microorganisms in human gastrointestinal tract had been coming. Each human body is a superorganism which is composed of 90% commensal microorganisms, especially the intestinal microorganisms. The intestinal microorganisms play an important role on health maintenance since they are involved in the absorption and metabolism of nutrients in the human bodies. Herein, we review the research progress in the mechanism of intestinal microorganisms in human diseases. Our purpose is to provide novel ideas on human health and therapeutic targets of diseases.


Assuntos
Microbioma Gastrointestinal , Intestinos/microbiologia , Metagenômica , Humanos , Simbiose
8.
Zhongguo Zhong Yao Za Zhi ; 41(10): 1766-1772, 2016 May.
Artigo em Zh | MEDLINE | ID: mdl-28895319

RESUMO

A large number and wide varieties of microorganisms colonize in the human gastrointestinal tract. They construct an intestinal microecological system in the intestinal environment. The intestinal symbiotic flora regulates a series of life actions, including digestion and absorption of nutrient, immune response, biological antagonism, and is closely associated with the occurrence and development of many diseases. Therefore, it is greatly essential for the host's health status to maintain the equilibrium of intestinal microecological environment. After effective compositions of traditional Chinese medicines are metabolized or biotransformed by human intestinal bacteria, their metabolites can be absorbed more easily, and can even decrease or increase toxicity and then exhibit significant different biological effects. Meanwhile, traditional Chinese medicines can also regulate the composition of the intestinal flora and protect the function of intestinal mucosal barrier to restore the homeostasis of intestinal microecology. The relevant literatures in recent 15 years about the interactive relationship between traditional Chinese medicines and gut microbiota have been collected in this review, in order to study the classification of gut microflora, the relationship between intestinal dysbacteriosis and diseases, the important roles of gut microflora in intestinal bacterial metabolism in effective ingredients of traditional Chinese medicines and bioactivities, as well as the modulation effects of Chinese medicine on intestinal dysbacteriosis. In addition, it also makes a future prospect for the research strategies to study the mechanism of action of traditional Chinese medicines based on multi-omics techniques.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Medicina Tradicional Chinesa , Disbiose/tratamento farmacológico , Humanos , Mucosa Intestinal/efeitos dos fármacos , Intestinos/microbiologia
9.
Chemistry ; 21(15): 5723-6, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25707447

RESUMO

A novel CBr4-mediated dehydrogenative Povarov/aromatization tandem reaction of glycine derivatives with alkenes, leading to complex quinoline derivatives, and a CBr4-mediated dehydrogenative C-H functionalization of N-aryl tetrahydroisoquinolines with nucleophiles to form C-C and C-P bonds are reported. The reactions were performed under very simple and mild reaction conditions; only CBr4 was used as a promoter. A plausible mechanism involving a radical process is proposed.

10.
J Org Chem ; 79(20): 9860-4, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25244546

RESUMO

A catalytic amount of triarylaminium salt is demonstrated to be an efficient initiator for oxidative Mannich reaction of tertiary amines and nonactivated ketones under mild neutral conditions. Air is essential for this reaction and acts as a terminal oxidant. Metal catalysts, acid or base additives, and stoichiometric amounts of chemical oxidants are all avoided in this methodology. Six examples of intramolecular cyclized products are also delivered.

11.
Org Biomol Chem ; 12(19): 3123-8, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24710317

RESUMO

A novel stable radical cation triarylaminium salt able to induce aerobic oxidative α-C-H functionalization of tertiary amines in catalytic amounts has been developed. The reaction is performed in the absence of any other additives under mild conditions and only requires atmosphere air as a sustainable co-oxidant.

12.
Biology (Basel) ; 13(6)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38927252

RESUMO

The gut microbiota constitutes a complex ecosystem that has an important impact on host health. In this study, genetically engineered zebrafish with inducible nitric oxide synthase (iNOS or NOS2) knockout were used as a model to investigate the effects of nos2a/nos2b gene single knockout and nos2 gene double knockout on intestinal microbiome composition and function. Extensive 16S rRNA sequencing revealed substantial changes in microbial diversity and specific taxonomic abundances, yet it did not affect the functional structure of the intestinal tissues. Notably, iNOS-deficient zebrafish demonstrated a decrease in Vibrio species and an increase in Aeromonas species, with more pronounced effects observed in double knockouts. Further transcriptomic analysis of the gut in double iNOS knockout zebrafish indicated significant alterations in immune-related and metabolic pathways, including the complement and PPAR signaling pathways. These findings underscore the crucial interplay between host genetics and gut microbiota, indicating that iNOS plays a key role in modulating the gut microbial ecology, host immune system, and metabolic responses.

13.
ACS Appl Mater Interfaces ; 14(21): 24102-24112, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35603430

RESUMO

Pickering emulsions stabilized by bacteria acting as particle emulsifiers are new platforms for microbial transformations of hydrophobic chemicals. However, their high stability often hampers demulsification during downstream processing. Since the existing methods (like addition of surfactants) to demulsify bacteria-stabilized Pickering emulsions have negative effects, new practical methods need to be developed. Here, using chemically modified fumed silica particles with different hydrophobicity, the demulsification of W/O Pickering emulsions stabilized by Mycobacterium neoaurum whole cells was first studied. The binary particle-stabilized emulsions exhibited phase inversion and dewatering induced by the coalescence of W/O emulsions or creaming of O/W emulsions. The silica particle hydrophobicity and concentration were the important parameters influencing the emulsion type, droplet morphology, and dewatering rate. The highest dewatering rate and largest droplet size were obtained at the inversion point from W/O to O/W. Confocal microscopy showed that no interaction between the bacteria and silica particles existed and the silica particle adsorption at the interface induced the detachment of bacteria from the interface, revealing that there was competitive adsorption between the binary particles at the interface. Based on these results, we suggested that the average hydrophobicity of the binary particles at the interface would determine the emulsion type and stability. Finally, this strategy was successfully applied to the demulsification of the Pickering emulsion formed during microbial transformation of sterols. Overall, this study provides a new strategy to demulsify Pickering emulsions by addition of another particle emulsifier. This is also the first example of separation of products as well as organic phases after microbial transformation in Pickering emulsions.


Assuntos
Nanopartículas , Dióxido de Silício , Bactérias , Emulsões/química , Nanopartículas/química , Dióxido de Silício/química , Tensoativos/química
14.
Cancers (Basel) ; 14(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35158838

RESUMO

Cancer stemness has been reported to drive hepatocellular carcinoma (HCC) tumorigenesis and treatment resistance. In this study, five HCC cohorts with 1059 patients were collected to calculate transcriptional stemness indexes (mRNAsi) by the one-class logistic regression machine learning algorithm. In the TCGA-LIHC cohort, we found mRNAsi was an independent prognostic factor, and 626 mRNAsi-related genes were identified by Spearman correlation analysis. The HCC stemness risk model (HSRM) was trained in the TCGA-LIHC cohort and significantly discriminated overall survival in four independent cohorts. HSRM was also significantly associated with transarterial chemoembolization treatment response and rapid tumor growth in HCC patients. Consensus clustering was conducted based on mRNAsi-related genes to divide 1059 patients into two stemness subtypes. On gene set variation analysis, samples of subtype I were found enriched with pathways such as DNA replication and cell cycle, while several liver-specific metabolic pathways were inhibited in these samples. Somatic mutation analysis revealed more frequent mutations of TP53 and RB1 in the subtype I samples. In silico analysis suggested topoisomerase, cyclin-dependent kinase, and histone deacetylase as potential targets to inhibit HCC stemness. In vitro assay showed two predicted compounds, Aminopurvalanol-a and NCH-51, effectively suppressed oncosphere formation and impaired viability of HCC cell lines, which may shed new light on HCC treatment.

15.
Nat Commun ; 13(1): 1232, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264579

RESUMO

Most cancer causal variants are found in gene regulatory elements, e.g., enhancers. However, enhancer variants predisposing to hepatocellular carcinoma (HCC) remain unreported. Here we conduct a genome-wide survey of HCC-susceptible enhancer variants through a three-stage association study in 11,958 individuals and identify rs73613962 (T > G) within the intronic region of PRMT7 at 16q22.1 as a susceptibility locus of HCC (OR = 1.41, P = 6.02 × 10-10). An enhancer dual-luciferase assay indicates that the rs73613962-harboring region has allele-specific enhancer activity. CRISPR-Cas9/dCas9 experiments further support the enhancer activity of this region to regulate PRMT7 expression. Mechanistically, transcription factor HNF4A binds to this enhancer region, with preference to the risk allele G, to promote PRMT7 expression. PRMT7 upregulation contributes to in vitro, in vivo, and clinical HCC-associated phenotypes, possibly by affecting the p53 signaling pathway. This concept of HCC pathogenesis may open a promising window for HCC prevention/treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína-Arginina N-Metiltransferases , Alelos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Cromossomos Humanos Par 16 , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Polimorfismo de Nucleotídeo Único , Proteína-Arginina N-Metiltransferases/genética
16.
Org Lett ; 23(17): 6784-6788, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34406020

RESUMO

A photocatalyzed in situ denitrogenative sulfonylation of N-arylsulfonyl hydrazones has been developed. This transformation provides a low-carbon strategy to assemble arylalkyl sulfones in a stepwise denitrogenation/sulfonylation manner.

17.
J Hepatocell Carcinoma ; 8: 1055-1064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513747

RESUMO

PURPOSE: Activation of actin cytoskeleton remodeling is an important stage preceding cancer cell metastasis. Previous genome-wide association studies (GWAS) have identified multiple hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC)-associated risk loci. However, limited sample size or strict significance threshold of GWAS may cause HBV-related HCC risk-associated genetic loci to be undetected. We aimed to investigate the performance of the SNP rs13025377 in PPP1CB in HCC. PATIENTS AND METHODS: We performed a case-control study including 1161 cases and 1353 controls to evaluate associations between single nucleotide polymorphisms (SNPs) from 98 actin-cytoskeleton regulatory genes and risk of HBV-related HCC. The effects of SNPs on HBV-related HCC risk were assessed under logistic regression model and corrected by false discovery rate (FDR). RESULTS: We found that rs13025377 in PPP1CB was significantly associated with HBV-related HCC risk [odds ratio (OR) = 0.81, 95% confidence interval (CI) = 0.72~0.91, P = 4.88×10-4]. The risk allele A of rs13025377 increased PPP1CB expression levels in normal liver tissue. SNP rs4665434 was tagged by rs13025377 (r2 = 0.9) and its protective allele disrupted CTCF and Cohesin motifs. According to public datasets, PPP1CB, CTCF and Cohesin expression levels are increased in tumor tissues. Kaplan-Meier plots demonstrated that higher PPP1CB expression was significantly associated with shorter overall survival (OS). Moreover, we observed strong correlation between CTCF, Cohesin, and PPP1CB in various liver tissues. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis confirmed that PPP1CB plays a role in HCC through actin-cytoskeleton regulation. CONCLUSION: Thus, these findings indicated that PPP1CB may be a key gene in actin-cytoskeleton regulation and rs13025377 contributes to the risk of HBV-related HCC by regulating PPP1CB expression.

18.
Org Lett ; 23(17): 6724-6728, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34397220

RESUMO

An unprecedented Pd/Rh cooperatively catalyzed arylalkynylation of alkynylsilanes was developed to merge an alkynylidene moiety with benzosilacycle. These silaarenes possess a particular aggregation-induced emission behavior. Mechanistic investigations demonstrate that the relay trimetallic transmetalation plays a pivotal role in governing this transformation.

19.
Org Lett ; 21(8): 2804-2807, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30945872

RESUMO

Visible-light-induced cross-coupling of arylsulfonyl azides with tertiaryamines in the presence of Eosin Y at room temperature has been achieved. This transformation features alkyl C-C bond cleavage and provides a green approach to N-sulfonylamidines under mild conditions.

20.
Org Lett ; 21(9): 3427-3430, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-30998018

RESUMO

A Co(II)-catalyzed pyridyl C-H bond carbenoid insertion with α-diazoacetates has been realized. This transformation features a highly regioselective C-C bond formation at the C3-position of pyridines, providing an efficient access to diverse α-aryl-α-pyridylacetates.

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