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Honokiol attenuates diabetes by enriching Akkermansia muciniphila andregulating tryptophan metabolism in mice
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作者 Yang Lin Zhengmeng Jiang +7 位作者 Zhilu Yu Tianqing Huang Wanyu Gui Ziyuan Wang Fei Li Pingting Xiao Changyin Li Ehu Liu 《Chinese Journal of Natural Medicines》 2026年第1期59-72,共14页
Diabetes mellitus(DM)is a chronic disease influenced by gut microbiome disturbances.Honokiol(HON),a low oral bioavailability compound from Magnolia officinalis bark,has demonstrated potential as a treatment for DM.Thi... Diabetes mellitus(DM)is a chronic disease influenced by gut microbiome disturbances.Honokiol(HON),a low oral bioavailability compound from Magnolia officinalis bark,has demonstrated potential as a treatment for DM.This research investigates the effects of HON on gut microbiota and host metabolism to elucidate its mechanism of action in DM.After 8 weeks of intervention through fecal microbiota transplantation(FMT)or antibiotic treatment,HON improved glucose tolerance and lipid metabolism in a gut microbiota-dependent manner.Specifically,HON administration significantly increased Akkermansia muciniphila(AKK)abundance and modulated tryptophan(TRP)metabolism,as evidenced by 16S ribosomal ribonucleic acid(rRNA)gene sequencing and untargeted/targeted metabolomics analysis.Notably,research revealed that AKK metabolized TRP into tryptamine(TA)and other metabolites in vitro.Both AKK and TA activated the aryl hydrocarbon receptor(AHR)pathway,increasing circulating glucagon-like peptide-1(GLP-1)levels and ameliorating diabetes-related symptoms in DM mice.These findings indicate that HON’s hypoglycemic effect primarily stems from AHR-GLP-1 pathway activation through targeted modulation of AKK and microbial TRP metabolite TA,potentially enhancing HON’s clinical applications. 展开更多
关键词 HONOKIOL Diabetes mellitus Akkermansia muciniphila TRYPTAMINE Aryl hydrocarbon receptor
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Natural Killer Cell Cytotoxicity:STAT3 Interactions with NF-κB Dimer Composition Modulate Mitochondrial Melatonergic Pathway:Tumor, and Viral Infection Treatment Implications
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作者 George Anderson 《BIOCELL》 2026年第2期23-42,共20页
As natural killer(NK)cells eliminate cancer cells and virus-infected cells,as well as modulate various other medical conditions,including aging-associated conditions such as neurodegenerative disorders,understanding N... As natural killer(NK)cells eliminate cancer cells and virus-infected cells,as well as modulate various other medical conditions,including aging-associated conditions such as neurodegenerative disorders,understanding NK cell regulation is of considerable clinical importance.This article reviews the role of circadian processes(melatonin and the cortisol system),aryl hydrocarbon receptor,and vagal nerve in the modulation of NK cell function,highlighting the importance of the endogenous mitochondrial melatonergic pathway in NK cells.As circadian and exogenous melatonin increase NK cell cytotoxicity,the presence of the endogenous melatonergic pathway may be of some importance not only to NK function and immune checkpoint regulation but also from the efflux of melatonin,which decreases tumor cell survival,proliferation,and metastasis,as well as decreasing immune checkpoint ligands,such as programmed cell ligand 1(PD-L1).NK cell melatonergic pathway regulation may therefore have significant impacts not only on NK cell cytotoxicity but also on the intercellular interactions within tumors and other pathological microenvironments.As melatonin has anti-viral effects,the regulation of the NK cell melatonergic pathway can have wider impacts on how NK cells regulate viral infections,including in the course of viral-induced susceptibility to neurodegenerative conditions.Recent data indicate that the endogenous melatonergic pathway is regulated by interactions of signal transducer and activator of transcription(STAT)3 and nuclear factor kappa-light-chain-enhancer of activated B cells(NF-κB)dimer composition.As both STAT3 and NF-κB dimer composition modulate NK cells,their interaction in the modulation of the NK cell melatonergic pathway will be important to determine.This has significant future research and treatment implications,including improving the clinical efficacy of current treatment approaches such as immune checkpoint inhibition and chimeric antigen receptor(CAR)NK cell therapy,and may accelerate a means of preventing cancer. 展开更多
关键词 Natural killer cells MELATONIN cancer viral infection vagal nerve aryl hydrocarbon receptor TREATMENT aging type 2 diabetes mellitus CIRCADIAN
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TDO2-Associated Tryptophan Metabolism Correlates with Impaired Tertiary Lymphoid Structure Maturation and Reduced B Cell Class Switching in Breast Cancer
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作者 Weiping Yang Wei Xiao +4 位作者 Wenhao Xu Lijun Ren Xian Li Junhua Yu Ronghua Wang 《Oncology Research》 2026年第3期667-690,共24页
Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryp... Background:Tertiary lymphoid structures(TLSs)promote antitumor immunity and predict favorable immunotherapy outcomes in breast cancer.The study aimed to investigate how Tryptophan 2,3-dioxygenase(TDO2)-associated tryptophan metabolism influences TLS maturation and B cell class switching in breast cancer.Methods:Bulk transcriptomic data from The Cancer Genome Atlas-Breast Invasive Carcinoma(TCGA-BRCA,n=1055)were analyzed using Gene Set Variation Analysis(GSVA)-based metabolic scoring,immune deconvolution,and TLS quantification.Single-cell RNA sequencing(scRNA-seq,n=26)and spatial transcriptomics(n=1)were applied to map TDO2 expression and TLS spatial organization.Validation was performed by immunohistochemistry(n=38)and multiplex immunofluorescence(n=12).Results:We identified that elevated tryptophan metabolism was predominantly enriched in the Luminal A subtype and delineates an immune-cold phenotype with less immunogenicity,associated with a distinct immune-dominant cellular microenvironment,particularly enriched in T and plasma cells.High expression of the tryptophan-metabolizing enzyme TDO2 was significantly enriched in TLS-low tumors and negatively correlated with TLS maturation signatures.Functional enrichment revealed suppressed B cell class switching and attenuated C-X-C motif chemokine ligand 9(CXCL9)expression in TLS-deficient tumors.Spatial transcriptomics and hotspot analysis demonstrated an inverse spatial correlation between TDO2 expression and TLS core components.Tumors with high tryptophan metabolism showed decreased cluster of differentiation 20(CD20)^(+)and CXCL9^(+)cell infiltration within TLS zones.Tumors with strong TDO2-kynurenine activity displayed impaired TLS organization and attenuated humoral immunity.Conditional spatial co-occurrence modeling confirmed reduced proximity between tryptophan metabolism hotspots and TLS-related immune features.Conclusion:In conclusion,our findings suggest that TDO2-associated tryptophan metabolism is linked to impaired TLS maturation and suppressed B cell class switching in breast cancer.Targeting the TDO2-kynurenine axis may represent a promising strategy to restore TLS formation and enhance immunotherapy responsiveness in breast cancer. 展开更多
关键词 Spatial transcriptomics KYNURENINE aryl hydrocarbon receptor(AhR) tryptophan 2 3-dioxygenase(TDO2) tertiary lymphoid structures(TLS) breast cancer tumor immune microenvironment
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CuI/4-Hydroxy Picolinohydrazide Catalyzed Coupling Reaction of(Hetero)aryl Chlorides with Sodium Aryl Sulfinates
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作者 Li Sailuo Ma Dawei 《有机化学》 北大核心 2025年第4期1276-1282,共7页
By using a newly developed 4-hydroxy picolinohydrazide as the ligand,Cu-catalyzed coupling of(hetero)aryl chlorides with sodium aryl sulfonates proceeded smoothly at 130℃to give a series of biarylsulfones in 53%~96%y... By using a newly developed 4-hydroxy picolinohydrazide as the ligand,Cu-catalyzed coupling of(hetero)aryl chlorides with sodium aryl sulfonates proceeded smoothly at 130℃to give a series of biarylsulfones in 53%~96%yields.This represents the first metal-catalyzed coupling reaction of(hetero)aryl chlorides with sodium aryl sulfonates.Aryl and heteroaryl chlorides bearing either electron-donating or electron-withdrawing groups were applicable for this coupling reaction. 展开更多
关键词 coupling reaction copper catalysis LIGAND (hetero)aryl chloride biarylsulfone
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Radical characteristic reactions in lignin pyrolysis:Aryl migration on linkages and substituents
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作者 Wenluan Xie Bin Hu +5 位作者 Guanzheng Zhou Ji Liu Zhimo Fang Zhenxi Zhang Xiaoyan Jiang Qiang Lu 《Journal of Energy Chemistry》 2025年第10期692-701,共10页
Lignin pyrolysis leads to the formation of diverse phenolic products that bear structural similarities to natural lignin,and the related mechanism has been widely explored based on the linkage cleavageinvolved reactio... Lignin pyrolysis leads to the formation of diverse phenolic products that bear structural similarities to natural lignin,and the related mechanism has been widely explored based on the linkage cleavageinvolved reactions.However,some unusual pyrolytic products exhibiting significant structure deviations from lignin,such as aldehydes,remain obscure in mechanism due to long-standing neglect of their formation pathways.The present work found the pivotal role of aryl migration,a special radical-mediated rearrangement process,in governing the formation of these atypical products for the first time.Herein,density functional theory calculations,electronic structure analyses,and pyrolysis experiments were combined to investigate rearrangement patterns and prerequisite structural characteristics of aryl migration by employing typical radicals derived from linkages and substituents of lignin as models.The results indicate that the radical with an unpaired electron located on the second atom of the aromatic side chain can undergo three-membered aryl 1,2-migration triggered by exo cyclization with the best superiority,determining the generation of aldehydes,alkenes,and other products through subsequent cleavage reactions.A clear correlation among the initial geometric and electronic structures of lignin,the patterns and types of aryl migration,the energy barriers,and the end products was established.This study contributes to systematically elucidating rearrangement mechanisms and constructing a more comprehensive lignin pyrolysis mechanism network. 展开更多
关键词 LIGNIN PYROLYSIS Radical mechanism REARRANGEMENT Aryl migration
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Denitrative iodination of nitroarenes with hydroiodic acid
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作者 Qingxuan Kong Changwei Jiang +3 位作者 Bin Lyu Zhaoting Li Ning Jiao Song Song 《Chinese Chemical Letters》 2025年第10期312-317,共6页
We herein present an efficient denitrative iodination method of(hetero)nitroarenes mediated by commercially available and cost-effective hydroiodic acid(HI).During the reaction process,HI plays its dual roles as both ... We herein present an efficient denitrative iodination method of(hetero)nitroarenes mediated by commercially available and cost-effective hydroiodic acid(HI).During the reaction process,HI plays its dual roles as both the sustainable reductant of nitro group and iodine source in the iodination step,which successfully integrates three steps into a one-pot procedure and significantly simplifies the reaction system.This approach enables a smooth metal-free conversion of nitroarenes to corresponding aryl iodides via one-pot process,exhibits a broad substrate scope and good reaction efficiency,and was conveniently applied in the concise synthesis of pharmaceuticals. 展开更多
关键词 Denitrative reaction Sandmeyer reaction IODINATION NITROARENES Aryl iodides
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Electrochemically Driven Nickel-Catalyzed Phenol Synthesis via Sustainable Oxygen Atom Transfer from Nitrous Oxide
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作者 Qiyu Zhang Wenbin Xie +3 位作者 Yasser M.A.Mohamed Hossam A.El Nazer Ahmed A.Elnazer Yinghui Han 《Journal of Electronic Research and Application》 2025年第2期18-22,共5页
The valorization of nitrous oxide(N_(2)O)as an oxygen atom donor presents an attractive opportunity for green chemistry applications,leveraging both its industrial abundance and thermodynamically favorable oxidation p... The valorization of nitrous oxide(N_(2)O)as an oxygen atom donor presents an attractive opportunity for green chemistry applications,leveraging both its industrial abundance and thermodynamically favorable oxidation potential.However,practical implementation has been constrained by the inherent kinetic inertness and poor coordinating ability of N_(2)O.While prior studies achieved N_(2)O-mediated conversion of aryl halides to phenols,such transformations necessitated stoichiometric chemical reductants and elevated pressure(2 atm),posing challenges in operational safety and process scalability.This study focuses on an electrochemical strategy that enables efficient oxygen atom transfer under ambient pressure through controlled current application.This methodology facilitates the selective transformation of aryl iodides to phenols without external reducing agents,establishing an environmentally benign synthetic pathway.By replacing traditional chemical reductants with electrons as the sole reducing equivalent,our approach addresses critical sustainability challenges in aromatic oxygenation chemistry while maintaining operational simplicity under mild conditions. 展开更多
关键词 Nitrous oxide Electrochemical synthesis Aryl iodides Revalorization Nickel-catalysis
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Ozone controls the metabolism of tryptophan protecting against sepsis-induced intestinal damage by activating aryl hydrocarbon receptor
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作者 Qing Wang Chun-Zheng Liu +5 位作者 Bai-Tian Li Xiu-Qin Yu Jin-Yuan Zhang Ze-Tian Wang Li-Jun Liao Xiao-Dong Liu 《World Journal of Gastroenterology》 2025年第17期40-55,共16页
BACKGROUND Intestinal injury is the most common complication of sepsis,and the mitigation of intestinal damage is crucial for treating sepsis.AIM To examine the use of ozone-rich water and its action in preventing int... BACKGROUND Intestinal injury is the most common complication of sepsis,and the mitigation of intestinal damage is crucial for treating sepsis.AIM To examine the use of ozone-rich water and its action in preventing intestinal damage caused by sepsis.METHODS Through histological analysis,immunohistochemistry,immunofluorescence assays,and Western blot detection,we evaluated the therapeutic efficacy of ozone in mitigating intestinal injury during sepsis.Additionally,by conducting 16S rRNA sequencing and untargeted metabolomics analysis on fecal samples,we identified alterations in the gut microbiota and specific metabolites in septic mice following ozone treatment.This comprehensive approach aims to further elucidate the mechanistic underpinnings of ozone therapy in alleviating sepsis-induced intestinal damage.RESULTS Our results demonstrate that ozonated water significantly ameliorates pathological damage in intestinal tissues,enhances the expression of tight junction proteins,and inhibits the polarization of intestinal macrophages,thereby reducing the expression of inflammatory cytokines in intestinal tissues of cecal ligation and puncture-induced septic mice.16S rRNA sequencing analysis revealed that ozonated water increased the abundance of beneficial bacteria and alleviated gut microbiota dysbiosis.Studies using broad-spectrum antibiotic-treated mice indicated that the protective effects of ozonated water on intestinal injury are dependent on the gut microbiota.Furthermore,metabolomic analysis identified an increase in the tryptophan metabolite DL-tryptophan in the ozonated water treatment group.This suggests that ozonated water protects against intestinal injury by activating the aryl hydrocarbon receptor and suppressing necroptosis in intestinal epithelial cells.CONCLUSION Ozone protected against sepsis-induced intestinal injury through regulation of the gut microbiota and tryptophan metabolism,inhibiting necrotic apoptosis of intestinal epithelial cells through activation of the aryl hydrocarbon receptor. 展开更多
关键词 DL-tryptophan NECROPTOSIS Aryl hydrocarbon receptor Intestinal flora Intestinal injury SEPSIS
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One-pot accessing of meso–aryl heptamethine indocyanine NIR fiuorophores and potential application in developing dye-antibody conjugate for imaging tumor
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作者 Mengxing Liu Jing Liu +4 位作者 Hongxing Zhang Jianan Tao Peiwen Fan Xin Lv Wei Guo 《Chinese Chemical Letters》 2025年第4期332-337,共6页
In this work, we put forward a new and universal approach, i.e., cyanine ketone method, for fabricating meso–aryl heptamethine indocyanines, which is so simple that the treatment of the easy-to-get cyanine ketones wi... In this work, we put forward a new and universal approach, i.e., cyanine ketone method, for fabricating meso–aryl heptamethine indocyanines, which is so simple that the treatment of the easy-to-get cyanine ketones with various aromatic lithium(Ar Li), followed by acidification, could straightforwardly give rise to the products in one-pot way. Importantly, due to the strong nucleophilicity of Ar Li, a series of bulky hydrophilic aromatic groups can be facilely integrated into the meso–position of heptamethine indocyanines, not only effectively inhibiting the undesired dye self-aggregation but also largely improving the water-solubility. Using one of anti-aggregation meso–aryl heptamethine indocyanines, we fabricated a dye-antibody conjugate for in vivo imaging tumor in a mouse model and achieved a high tumor-tonormal tissue ratio. The work laid a chemical foundation for constructing various meso–aryl heptamethine indocyanines, facilitating the advanced imaging and therapeutic applications in future. 展开更多
关键词 Heptamethine indocyanines Aryl substituents Aromatic lithium reagents Protein labeling Imaging tumor
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Microbiome-derived metabolites in cancer-associated anemia:An underexplored mechanistic link
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作者 Zhe Wang Feng Wang 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 2025年第3期80-82,共3页
The review by Bangolo et al highlights the role of the gut microbiome in cancerassociated anemia(CAA).However,the impact of microbiome-derived metabolites is underexplored.In this letter,we focus on short-chain fatty ... The review by Bangolo et al highlights the role of the gut microbiome in cancerassociated anemia(CAA).However,the impact of microbiome-derived metabolites is underexplored.In this letter,we focus on short-chain fatty acids,tryptophan metabolites,and polyamines as key mediators linking dysbiosis to impaired erythropoiesis and iron homeostasis.We also propose a research framework that integrates multi-omics analysis and gnotobiotic models.Finally,we discuss the clinical potential of metabolite-based diagnostics and microbiome-targeted therapies in managing CAA. 展开更多
关键词 Cancer-associated anemia Gut microbiota Microbial metabolites Short-chain fatty acids TRYPTOPHAN Aryl hydrocarbon receptor
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Electrochemical demethoxyl-cyanation of methoxyarenes via S_(N)Ar
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作者 Shuai Chen Anzai Shi +3 位作者 Guoqing Yang Pengfei Xie Feng Liu Youai Qiu 《Chinese Chemical Letters》 2025年第9期305-310,共6页
Herein,a metal-free electrochemical demethoxyl-cyanation of methoxyarenes via aromatic nucleophilic substitution(S_(N)Ar) using TMSCN as a cheap cyanide source under mild conditions has been presented.This transformat... Herein,a metal-free electrochemical demethoxyl-cyanation of methoxyarenes via aromatic nucleophilic substitution(S_(N)Ar) using TMSCN as a cheap cyanide source under mild conditions has been presented.This transformation utilizes commercially available reagents,cheap electrodes,and simple equipment.Diverse aryl nitriles were successfully obtained in a direct and efficient way with broad substrate scope,excellent functional group tolerance,and selective C-O bond cleavage.Furthermore,late-stage modification of biorelevant compounds and gram-scale synthesis highlighted the potential application of the strategy.Mechanistic investigations suggest that the arene cation radical was considered as the key intermediate for the transformation,and undergoing the followed S_(N)Ar process. 展开更多
关键词 ELECTROCHEMISTRY Aromatic nucleophilic substitution(SNAr) CYANATION Aryl nitriles Organic electrosynthesis
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Influence of Bromo-Aromatic Substrates on Direct Arylation of EDOTs toward Higher Molecular Conjugate Polymer
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作者 Xi-Lin Pei Quan Yang +3 位作者 Yan-Lu Sun Wei Wu Jian-Yong Yu Yong He 《Chinese Journal of Polymer Science》 2025年第5期718-729,共12页
The influence of the electronic and steric properties of bromoaromatic substrates on direct arylation polymerization for synthesizing high-molecular-weight conjugated polymers was investigated through a combination of... The influence of the electronic and steric properties of bromoaromatic substrates on direct arylation polymerization for synthesizing high-molecular-weight conjugated polymers was investigated through a combination of experiments and calculations.Bromo-aromatic substrates with electron-withdrawing fluoro substituents exhibited higher yields and degrees of polymerization under PPh3-assisted conditions compared to those with electron-donating or bulky methyl substituents.Additionally,excessive steric hindrance at ortho-sites or overly electrondeficient dibromoaromatic substrates leads to reaction inactivation.Calculations indicated that electron-withdrawing substituents enhanced the electrophilicity of arylpalladium-PPh3intermediates,facilitating the activation of electron-rich arylative substrates and promoting polymer growth.Furthermore,steric hindrance from the substituents can influence the preferred reaction pathway,thereby increasing the real reaction barriers.Both experimental and computational results suggest that bromoaromatic substrates with optimized electron-deficient characteristics significantly improve monomer conversion and polymerization efficiency with n-hexylmethylether-substituted EDOT.These findings clarify how the electronic and steric properties of bromo-aromatic substrates affect EDOT derivative activation and are expected to aid in optimizing the polymerization conditions for the preparation of high-molecular-weight conjugated polymers. 展开更多
关键词 3 4-Ethylenedioxythiophene Direct arylation polymerization Bromo-aromatic substrate Concerted metalation-deptonation
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Lactiplantibacillus plantarum DPUL-S164 regulate aryl hydrocarbon receptors signaling to ameliorate dextran sodium sulfate-induced intestinal barrier damage by producing indole-3-lactic acid in a tryptophan-rich diet
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作者 Arong Wang Dashuai He +3 位作者 Tieqi Wang Cheng Guan Guangqing Mu Yanfeng Tuo 《Food Science and Human Wellness》 2025年第3期981-997,共17页
The aim of this paper was to study the effect of combination of Lactobacillus strains and tryptophan(Trp)-rich diet on the intestinal barrier function of Balb/c mice exposed to a cocktail of antibiotics and dextran so... The aim of this paper was to study the effect of combination of Lactobacillus strains and tryptophan(Trp)-rich diet on the intestinal barrier function of Balb/c mice exposed to a cocktail of antibiotics and dextran sodium sulfate.Several Lactobacillus strains isolated from the healthy human fecal sample was found to utilize Trp to produce indole derivatives.The results of Trp metabolism indicated that the ability of Lactobacillus to metabolize Trp to produce indole-3-lactic acid(ILA),indole-3-carboxaldehyde(I3C),and indole-3-acetic acid varies in vitro and in vivo.The effect of Lactobacillus with high-yielding indole derivatives on disease activity index,colon length,and intestinal permeability was significantly better than that of Lactobacillus with low-yielding indole derivatives in a high Trp diet.And Lactobacillus combined with Trp intervention also had a certain regulatory effect on the intestinal flora of male BALB/c mice.Among them,Lactiplantibacillus plantarum DPUL-S164 produced more ILA both in vivo and in vitro,and the combination of L.plantarum DPUL-S164 and Trp significantly decreased the expression level of the serum pro-inflammatory cytokine interleukin(IL)-6 and increased the expression level of the anti-inflammatory cytokine IL-10,significantly improved the number of goblet cells in the mouse mucous layer and increased mucin and tight junction protein expression.Furthermore,L.plantarum DPUL-S164 combined with Trp intervention activated the aryl hydrocarbon receptors(Ah R)signaling pathway.Furthermore,we found that the expression of colonic tight junction protein was positively correlated with the expression of colonic Ah R,and the expression of Ah R was positively correlated with the concentrations of ILA and I3C in vivo.Therefore,we conclude that the ILA as Ah R ligand produced by L.plantarum DPUL-S164 regulated the Ah R pathway,thus up-regulating the expression of the tight junction protein and protecting the integrity of the epithelial barrier. 展开更多
关键词 Intestinal barrier injury LACTOBACILLUS Aryl hydrocarbon receptor Indole-3-lactic acid
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Asymmetric conjugated addition of aryl Grignard reagents for the construction of chromanones bearing quaternary stereogenic centers in batch and flow
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作者 Ya-Ling Li Jia-Wei Ke +4 位作者 Yue Liu Dong-Mei Yao Jing-Dong Zhang You-Cai Xiao Fen-Er Chen 《Chinese Chemical Letters》 2025年第6期439-445,共7页
The asymmetric conjugate additions of aryl Grignard reagents to trisubstituted enones by chiral P,N ligand L6 with low catalyst loading(0.25–1.0 mol%)are disclosed.Chiral 2-ester chromanone and its analogs bearing a ... The asymmetric conjugate additions of aryl Grignard reagents to trisubstituted enones by chiral P,N ligand L6 with low catalyst loading(0.25–1.0 mol%)are disclosed.Chiral 2-ester chromanone and its analogs bearing a quaternary stereogenic centers at C2 position were produced in high to excellent yields,enantioselectivities and high turnover number.The notable features of this reaction include its broad substrate scope,complete 1,4-addition regioselectivities,applicability to both batch and flow for large scale synthesis.This report develops an efficient strategy to apply aryl Grignard reagents in asymmetric 1,4-conjugation reactions and provides a direct method to incorporate quaternary chiral centers toward the synthesis of biologically relevant chromanone derivatives. 展开更多
关键词 Cyclic enones Aryl grignard reagents Chiral P N ligand Tetra-substituted chromanones Asymmetric conjugation
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Switching electronic effects of UiO-67-Pd using fluorinated ligands for catalytic oxidative arylation of bio-based furfuryl alcohol
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作者 Dongwen Guo Guohui Zeng +1 位作者 Jinxing Long Biaolin Yin 《Chinese Journal of Catalysis》 2025年第2期230-240,共11页
An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthrolin... An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthroline/bipyridine,and poly-F substituted phenyl ligands as the mixture linkers.The results of control experiments and theoretical calculations reveal that the–F on the phenyl linkers efficiently tunes the electron-deficient nature of Pd through the Zr_(6) clusters bridges,which favors the adsorption and activation of the furan ring.Furthermore,the conjugation of different nitrogen-containing ligands facilitates Pd coordination for the Heck-type insertion and subsequent electrophilic palladation,respectively.As a result,the oxidative arylation of FA derivatives is substantially enhanced because of these electronic and steric synergistic effects.Under the optimized conditions,72.2%FA conversion and 74.8%mono aryl furan(MAF)selectivity are shown in the Heck-type insertion.Meanwhile,85.3%of MAF is converted,affording 74.8%selectivity of final product(AFs)in the subsequent electrophilic palladation reaction.This process efficiency is remarkably higher than that with homogeneous catalysts.In addition,furan-benzene polymer obtained from the halogen-free synthesis catalyzed by UiO-67-Pd(F)show significantly better properties than that from conventional Suzuki coupling method.Therefore,the present work provides a new insight for useful AFs synthesis by oxidative arylation of bio-furan via rational tunning the metal center micro-environment of heterogeneous catalyst. 展开更多
关键词 Bio-based furan Catalytic oxidative arylation UiO-67-Pd(F)catalyst Ligand regulation Charge separation
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Catalytic asymmetric inverse-electron-demand Diels-Alder reaction of 2-pyrones with aryl enol ethers
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作者 Fangqing Zhang Yu Wang +3 位作者 Zhenda Tan Yangbin Liu Lijuan Song Xiaoming Feng 《Chinese Chemical Letters》 2025年第7期364-370,共7页
Chiral aryl cyclohex-3-en ether scaffold is widely present in bioactive natural products and drugs.The exploitation of efficient and enantioselective methods for the construction of aryl cyclohex-3-en ether scaffold i... Chiral aryl cyclohex-3-en ether scaffold is widely present in bioactive natural products and drugs.The exploitation of efficient and enantioselective methods for the construction of aryl cyclohex-3-en ether scaffold is significant.Herein we disclose a chiral N,N’-dioxide/Lewis acid complex-catalyzed asymmetric inverse-electron-demand Diels-Alder(IEDDA)reaction using electron-deficient 3-carboalkoxyl-2-pyrones and less electron-enriched aryl enol ethers as reactants.A wide range of non-and 1,2-disubstituted acyclic aryl enol ethers are applicable to deliver diverse chiral bridged bicyclic lactones in high yields and stereoselectivities(up to 96%yield,>20:1 dr,97:3 er).The bridged bicyclic lactone core can be easily converted into chiral aryl cyclohex-3-en ether scaffold.Notably,DFT calculations revealed a stepwise and endo mechanism to explain the high enantioselectivity controlled by the cooperative effect of the steric factors and the dispersion interactions between ligands and enol ethers. 展开更多
关键词 Asymmetric IEDDA reaction Aryl cyclohex-3-en ether scaffold 2-Pyrone Chiral Lewis acid complex Chiral bridged bicyclic lactones
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Mechanistic insights for Aryl dilithium base enables the acylation of unactivated C_(sp3)–H
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作者 Changming Li Hongdan Zhu +3 位作者 Can-Can Bao Yongjia Lin Bing-Tao Guan Qian Peng 《Chinese Chemical Letters》 2025年第9期299-304,共6页
Mechanistic studies of the cleavage and transformation of unactivated C_(sp3)-H bonds are a significant field of chemistry.Overcoming the inherent low acidity of C-H bonds to activate the inert substrates is challenge... Mechanistic studies of the cleavage and transformation of unactivated C_(sp3)-H bonds are a significant field of chemistry.Overcoming the inherent low acidity of C-H bonds to activate the inert substrates is challenge under mild conditions.And their complex multi-step transformations may also hinder mechanistic understanding.Herein,we perform theoretical calculations and experimental studies to explore the C_(sp3)-H bonds activation and acylation mechanisms of toluene/thioether using the relatively weak base LDA.A synergistic"main and auxiliary"model was revealed involving dual lithium metal by LDA dimers,and the aryl dilithium species as an intermediate base can facilitate C_(sp3)-H activation.This model not only aids in understanding the acidity of unactivated C_(sp3)-H bonds and the nucleophilicity of their conjugate bases for their kinetic control through cooperative interactions,but also predicts unusual kinetic isotope effects(KIE)for newly designed 2-(methylthio)naphthalene that are experimentally validated.This research is expected to provide a crucial scenario for the cleavage and transformation of unactivated C_(sp3)-H bonds and the development of new functionalities for alkali metal reagents. 展开更多
关键词 Acylation of unactivated C_(sp3)-H bonds Mechanistic studies LDA dimers Aryl dilithium base Acidity and nucleophilicity DFT calculations
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Environmentally benign and economic synthesis of covalent triazine-based frameworks 被引量:2
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作者 张玲 刘学 +2 位作者 杨瑞霞 黄年玉 邓伟侨 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期583-588,共6页
Covalent triazine-based frameworks(CTFs) are important microporous materials with a wide range of applications.Here,we demonstrate an environmentally benign and economic synthetic pathway to CTFs.The monomers used f... Covalent triazine-based frameworks(CTFs) are important microporous materials with a wide range of applications.Here,we demonstrate an environmentally benign and economic synthetic pathway to CTFs.The monomers used for CTFs,aromatic nitriles,were obtained by cyanation using nontoxic potassium hexacyanoferrate(Ⅱ) in place of commonly used toxic cyanides.Then,the CTFs were synthesized by trimerization of the corresponding cyano monomers in molten zinc chloride.A series of CTFs was synthesized,and the highest Brunauer-Emmett-Teller surface area measured in this series was 2404 m^2/g.Among the synthesized CTFs,CTF_(DCP) exhibited excellent CO_2 adsorption properties,with a CO_2 uptake of 225 mg/g at 0℃. 展开更多
关键词 Covalent triazine-based framework Aryl bromide CYANATION Potassium hexacyanoferrate(Ⅱ) Palladium acetate
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C–H Arylation using acyl thiourea ligands: Applications in the synthesis of 3,6-diaryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 被引量:1
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作者 Aamer Saeed Pervaiz Ali Channar +1 位作者 Qasir Iqbal Jamaluddin Mahar 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期37-40,共4页
Synthesis of a series of new 3,6-diaryl-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles(5a-o) was achieved by phophine free, C-H arylative cross-coupling of 6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles(4a-o)with su... Synthesis of a series of new 3,6-diaryl-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles(5a-o) was achieved by phophine free, C-H arylative cross-coupling of 6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles(4a-o)with suitably substituted iodoanilines using 1-(2-naphthoyl)-3-(4-bromophenyl)thiourea as a ligand.The requisite triazolothiadiazoles(4a-o) were obtained by the condensation of 4-amino-1,2,4-triazole-3-thiol(3) with suitably substituted aromatic acids in the presence of phosphoryl chloride. 展开更多
关键词 [1 2 4]Triazolo[3 4-b][1 3 4]thiadiazoles Acyl thiourea C-H arylative coupling N N-DIMETHYLACETAMIDE
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Studies on the Synthesis, Anticonvulsant Activity, and the Structure-Activity Relationships of Phenyl Pyridazinones and their GABA Derivatives
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作者 徐萍 王书玉 刘维勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第2期27-34,共8页
In searching for effective anticonvulsant agents,fourteen 6-aryl-4.5-di- hydro-3(2H)pyridazinones.fifteen 6-aryl-3(2H)pyridazinones,and seventeen 3-GABA derivatives of 6-aryIpyridazines have been synthesized,and evalu... In searching for effective anticonvulsant agents,fourteen 6-aryl-4.5-di- hydro-3(2H)pyridazinones.fifteen 6-aryl-3(2H)pyridazinones,and seventeen 3-GABA derivatives of 6-aryIpyridazines have been synthesized,and evaluated in mice for the ability to antagonize maximal electroshock seizure(MES).The ED_(50) values showed that 6-(2′,4′- dichlorophenyt)-3(2H)pyridazinone was the most potent anticonvulsant among these corn- pounds(ED_(50)=10.15 mg/kg).The structure-activity relationships of the aryl pyridazinones were studied.The result showed that:(1)the higher the value of the hydrophobic parameter л of the substituent on the phenyl ring.the more potent the anticonvulsant activity of the corn- pound.and(2)only the compounds with an electron withdrawing substituent on the phenyl ring exhibited appreciable anticonvulsant activity. 展开更多
关键词 Aryl pyridazinones 3-GABA-6-aryl pyridazines Anticonvulsant activity Structure-activity relationships
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