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
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
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
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
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
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
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
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
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
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
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
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
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
The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Never...The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes.展开更多
Enones are widely explored in synthetic chemistry as fundamental building blocks for a wide range of reactions and exhibit intriguing biological activities that are pivotal for drug discovery.The development of synthe...Enones are widely explored in synthetic chemistry as fundamental building blocks for a wide range of reactions and exhibit intriguing biological activities that are pivotal for drug discovery.The development of synthetic strategies for highly efficient preparation of enones thereby receives intense attention,in particular through the transition metal-catalyzed coupling reactions.Here,we describe a carbene-catalyzed cross dehydrogenative coupling(CDC)reaction that enables effective assembly of simple aldehydes and alkenes to afford a diverse set of enone derivatives.Mechanistically,the in situ generated aryl radical is pivotal to“activate”the alkene by forming an allyl radical through intermolecular hydrogen atom transfer(HAT)pathway and thus forging the carbon-carbon bond formation with aldehyde as the acyl synthon.Notably,our method represents the first example on the enone synthesis through coupling of“non-functionalized”aldehydes and alkenes as coupling partners,and offers a distinct organocatalytic pathway to the transition metal-catalyzed coupling transformations.展开更多
Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One k...Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One key player in this process is the Aryl Hydrocarbon Receptor(AhR),which influences multiple cellular processes,including proliferation,differentiation,metabolism,and immune regulation.Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis,epithelial-mesenchymal transition,and immune escape.Targeting AhR signaling is a potential therapeutic approach for ESCC,with AhR ligands showing efficacy in preclinical studies.Additionally,modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention.This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape.展开更多
Transition-metal-catalyzed remote sp^(2)C-H functionalization of aryl sulfonic acids was hardly ever real-ized owing to competitive ortho-C-H functionalization of aryl sulfonates and electron-deficient nature of pheny...Transition-metal-catalyzed remote sp^(2)C-H functionalization of aryl sulfonic acids was hardly ever real-ized owing to competitive ortho-C-H functionalization of aryl sulfonates and electron-deficient nature of phenyl ring.Herein,with the assistance of a practical biaryl indolyl directing template,palladium-catalyzed remote sp^(2)C-H alkylation of aryl sulfonic acids have been achieved in moderate to good yields with exclusive meta selectivity.Moreover,remote meta-selective C-H alkynylation of aryl sulfonic acids was also accomplished with a rhodium catalyst.These meta-C-H functionalized products proved to be the superior synthetic precursors,which are difficult to access using the conventional strategy.展开更多
Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed a...Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different crystallinities.According to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing crystallinity.The effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile tests.The tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced crystallization.Differential scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization behavior.The results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.展开更多
Atomically-dispersed metal-based materials represent an emerging class of photocatalysts attributed to their high catalytic activity,abundant surface active sites,and efficient charge separation.Nevertheless,the roles...Atomically-dispersed metal-based materials represent an emerging class of photocatalysts attributed to their high catalytic activity,abundant surface active sites,and efficient charge separation.Nevertheless,the roles of different forms of atomically-dispersed metals(i.e.,single-atoms and atomic clusters)in photocatalytic reactions remain ambiguous.Herein,we developed an ethylenediamine(EDA)-assisted reduction method to controllably synthesize atomically dispersed Au in the forms of Au single atoms(Au_(SA)),Au clusters(Au_(C)),and a mixed-phase of Au_(SA)and Au_(C)(Au_(SA+C))on CdS.In addition,we elucidate the synergistic effect of Au_(SA)and Au_(C)in enhancing the photocatalytic performance of CdS substrates for simultaneous CO_(2)reduction and aryl alcohol oxidation.Specifically,Au_(SA)can effectively lower the energy barrier for the CO_(2)→*COOH conversion,while Au_(C)can enhance the adsorption of alcohols and reduce the energy barrier for dehydrogenation.As a result,the Au_(SA)and Au_(C)co-loaded CdS show impressive overall photocatalytic CO_(2)conversion performance,achieving remarkable CO and BAD production rates of 4.43 and 4.71 mmol g^(−1)h^(−1),with the selectivities of 93%and 99%,respectively.More importantly,the solar-to-chemical conversion efficiency of Au_(SA+C)/CdS reaches 0.57%,which is over fivefold higher than the typical solar-to-biomass conversion efficiency found in nature(ca.0.1%).This study comprehensively describes the roles of different forms of atomically-dispersed metals and their synergistic effects in photocatalytic reactions,which is anticipated to pave a new avenue in energy and environmental applications.展开更多
We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challengin...We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product conjugates.Site selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal chemistry.Mechanism investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.展开更多
文摘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.
基金the National Key Research and Development Project(No.2023YFF1205103)the National Natural Science Foundation of China(No.22371007)the Peking University Medicine plus X Pilot Program-Key Technologies R&D Project(No.2024YXXLHGG001)for financial support。
文摘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.
基金National Natural Science Foundation of China(Project No.:52320105003,Project No.:52303019)the CAS-ANSO Co-funding Research Project(Project No.:CAS-ANSO-CF-2024)+2 种基金the National Key R&D Program of China(Project No.:2023YFC3707201)the Fundamental Research Funds for the Central Universities(Project No.:E3ET1803)China Postdoctoral Science Foundation(Project No:2024T170904)。
文摘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.
基金Supported by the National Natural Science Foundation of China,No.81971814Pudong New Area Health Talent Training Program,No.2025PDWSYCBJ-04Shanghai’s 2023“Technology Innovation Action Plan”Medical Innovation Research Project,No.23Y11908300。
文摘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.
基金supported by National Natural Science Foundation of China (Nos. 22277070, 22274091, 22007061)Youth Talent Support Program of Shanxi Province+1 种基金Program for the Top Young Academic Leaders of Higher Learning Institutions of ShanxiFundamental Research Program of Shanxi Province (No. 20210302123445)。
文摘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.
文摘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.
基金Financial support from National Key R&D Program of China(No.2023YFA1507203)National Natural Science Foundation of China(Nos.22371149,22188101)+2 种基金the Fundamental Research Funds for the Central Universities(No.63224098)Frontiers Science Center for New Organic Matter,Nankai University(No.63181206)the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘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.
基金project was supported by the National Key Research and Development Program(2021YFD2100700)。
文摘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.
文摘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.
基金the financial support from the Sichuan Science and Technology Program(No.2022NSFSC0619)。
文摘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.
文摘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.
基金National Natural Science Foundation of China(Nos.22001177,22203023)Guangdong Pearl River Talent Program(no.2021QN020268)+3 种基金the Natural Science Foundation of Guangdong Province(Nos.2024A1515012381,2022A1515011859)Shenzhen Bay Laboratory Startup Fund(No.S201100003)Major Program of Shenzhen Bay Laboratory(No.S211101001-4)Shenzhen Bay Qihang Fellow Program(No.QH23001)for generous financial support.
文摘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.
基金the National Key Research and Development Program of China(No.2021YFA1500100)the National Natural Science Foundation of China(Nos.92156017 and 21890722)+1 种基金“Frontiers Science Center for New Organic Matter”,Nankai University(No.63181206)Haihe Laboratory of Sustainable Chemical Transformation of Tianjin(No.24HHWCSS00019)for generous financial support。
文摘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.
基金supported by the National Natural Science Foundation of China(51978133,52100026,U20A20322,52170151,51978132)the Fundamental Research Funds for the Central Universities of China(2412021QD022)+1 种基金the Key Research and Development Project of Hainan Province(ZDYF2022SHFZ298)the Industrialization Cultivation Project of Jilin Provincial Department of Education(JJKH20221174CY)。
文摘The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes.
基金funding supports from the National Natural Science Foundation of China(Nos.21732002,22061007,22071036,and 22207022)Frontiers Science Center for Asymmetric Synthesis and Medicinal Molecules,National Natural Science Fund for Excellent Young Scientists Fund Program(Overseas),the starting grant of Guizhou University[No.(2022)47)]+10 种基金Department of Education,Guizhou Province[Qianjiaohe KY No.(2020)004]The 10 Talent Plan(Shicengci)of Guizhou Province(No.[2016]5649)Science and Technology Department of Guizhou Province(Nos.[Qiankehe-jichu-ZK[2022]zhongdian024],[2018]2802,[2019]1020,QKHJC-ZK[2022]-455)Department of Education of Guizhou Province(No.QJJ(2022)205)Program of Introducing Talents of Discipline to Universities of China(111 Program,No.D20023)at Guizhou UniversitySingapore National Research Foundation under its NRF Investigatorship(No.NRF-NRFI2016–06)Competitive Research Program(No.NRF-CRP22–2019–0002)Ministry of Education,Singapore,under its MOE Ac RF Tier 1 Award(Nos.RG7/20,RG70/21)MOE AcRF Tier 2(No.MOE2019-T2–2–117)MOE AcRF Tier 3 Award(No.MOE2018-T3–1–003)a Chair Professorship Grant,and Nanyang Technological University。
文摘Enones are widely explored in synthetic chemistry as fundamental building blocks for a wide range of reactions and exhibit intriguing biological activities that are pivotal for drug discovery.The development of synthetic strategies for highly efficient preparation of enones thereby receives intense attention,in particular through the transition metal-catalyzed coupling reactions.Here,we describe a carbene-catalyzed cross dehydrogenative coupling(CDC)reaction that enables effective assembly of simple aldehydes and alkenes to afford a diverse set of enone derivatives.Mechanistically,the in situ generated aryl radical is pivotal to“activate”the alkene by forming an allyl radical through intermolecular hydrogen atom transfer(HAT)pathway and thus forging the carbon-carbon bond formation with aldehyde as the acyl synthon.Notably,our method represents the first example on the enone synthesis through coupling of“non-functionalized”aldehydes and alkenes as coupling partners,and offers a distinct organocatalytic pathway to the transition metal-catalyzed coupling transformations.
文摘Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One key player in this process is the Aryl Hydrocarbon Receptor(AhR),which influences multiple cellular processes,including proliferation,differentiation,metabolism,and immune regulation.Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis,epithelial-mesenchymal transition,and immune escape.Targeting AhR signaling is a potential therapeutic approach for ESCC,with AhR ligands showing efficacy in preclinical studies.Additionally,modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention.This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape.
基金Financial support from the National Natural Science Foundation of China(No.22171145 to Z.Jin,32072440 to X.Xu)is gratefully acknowledged.
文摘Transition-metal-catalyzed remote sp^(2)C-H functionalization of aryl sulfonic acids was hardly ever real-ized owing to competitive ortho-C-H functionalization of aryl sulfonates and electron-deficient nature of phenyl ring.Herein,with the assistance of a practical biaryl indolyl directing template,palladium-catalyzed remote sp^(2)C-H alkylation of aryl sulfonic acids have been achieved in moderate to good yields with exclusive meta selectivity.Moreover,remote meta-selective C-H alkynylation of aryl sulfonic acids was also accomplished with a rhodium catalyst.These meta-C-H functionalized products proved to be the superior synthetic precursors,which are difficult to access using the conventional strategy.
基金financially supported by the National Key R&D Program of China (No.2022YFB3709402)。
文摘Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different crystallinities.According to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing crystallinity.The effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile tests.The tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced crystallization.Differential scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization behavior.The results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.
文摘Atomically-dispersed metal-based materials represent an emerging class of photocatalysts attributed to their high catalytic activity,abundant surface active sites,and efficient charge separation.Nevertheless,the roles of different forms of atomically-dispersed metals(i.e.,single-atoms and atomic clusters)in photocatalytic reactions remain ambiguous.Herein,we developed an ethylenediamine(EDA)-assisted reduction method to controllably synthesize atomically dispersed Au in the forms of Au single atoms(Au_(SA)),Au clusters(Au_(C)),and a mixed-phase of Au_(SA)and Au_(C)(Au_(SA+C))on CdS.In addition,we elucidate the synergistic effect of Au_(SA)and Au_(C)in enhancing the photocatalytic performance of CdS substrates for simultaneous CO_(2)reduction and aryl alcohol oxidation.Specifically,Au_(SA)can effectively lower the energy barrier for the CO_(2)→*COOH conversion,while Au_(C)can enhance the adsorption of alcohols and reduce the energy barrier for dehydrogenation.As a result,the Au_(SA)and Au_(C)co-loaded CdS show impressive overall photocatalytic CO_(2)conversion performance,achieving remarkable CO and BAD production rates of 4.43 and 4.71 mmol g^(−1)h^(−1),with the selectivities of 93%and 99%,respectively.More importantly,the solar-to-chemical conversion efficiency of Au_(SA+C)/CdS reaches 0.57%,which is over fivefold higher than the typical solar-to-biomass conversion efficiency found in nature(ca.0.1%).This study comprehensively describes the roles of different forms of atomically-dispersed metals and their synergistic effects in photocatalytic reactions,which is anticipated to pave a new avenue in energy and environmental applications.
基金support from the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(No.UNPYSCT-2017124)。
文摘We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product conjugates.Site selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal chemistry.Mechanism investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.
