Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Ecol Evol ; 14(6): e11577, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873020

RESUMO

Understanding the processes and mechanisms that shape the distribution patterns and variations of biodiversity along spatial gradients continues to be a priority for ecological research. We focused on the biodiversity of benthic diatom communities within a large near-natural watershed. The objectives are: (1) to explore the overall spatial patterns of benthic diatom biodiversity; (2) to investigate the effects associated with watercourse position and environmental variables, as well as both common and rare species on two facets (i.e., taxonomic and functional) of alpha and beta diversity; and (3) to unveil the mechanisms underlying their spatial variations. Alpha diversity indices along the stream watercourse showed a clear increasing trend from upstream to downstream sites. Results of random forest regression identified conductivity as the primary factor influencing functional alpha diversity, while elevation emerged as the predominant factor for taxonomic alpha diversity. Beta diversity partitioning revealed that taxonomic beta diversity generally exceeded functional beta diversity. These diversity measures exhibited different patterns along the watercourse position: taxonomic beta diversity remained relatively consistent along the watercourse, whereas functional total beta diversity and its two components of middle stream sites were lower than those of upstream and downstream sites. Functional beta diversity was sustained by dominant and common species, while rare species made significant contributions to taxonomic beta diversity. Both taxonomic and functional beta diversity and its components displayed a stronger influence from spatial factors than from local environmental, geo-climatic, and nutrient variables. Collectively, taxonomic and functional alpha and beta diversity demonstrated distinct responses to the main environmental gradients and spatial factors within our catchment, highlighting their different insights into diatom diversity. Furthermore, research is required to assess the generalizability of our findings to similar ecosystems. In addition, this study presents opportunities for expansion to include other taxa (e.g., macroinvertebrates and fish) to gain a comprehensive understanding of the driving mechanisms behind stream biodiversity.

2.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673868

RESUMO

This study aimed to investigate the preventive effects of the total polyphenols from Nymphaea candida (NCTP) on LPS-induced septic acute lung injury (ALI) in mice and its mechanisms. NCTP could significantly ameliorate LPS-induced lung tissue pathological injury in mice as well as lung wet/dry ratio and MPO activities (p < 0.05). NCTP could significantly decrease the blood leukocyte, neutrophil, monocyte, basophil, and eosinophil amounts and LPS contents in ALI mice compared with the model group (p < 0.05), improving lymphocyte amounts (p < 0.05). Moreover, compared with the model group, NCTP could decrease lung tissue TNF-α, IL-6, and IL-1ß levels (p < 0.05) and downregulate the protein expression of TLR4, MyD88, TRAF6, IKKß, IκB-α, p-IκB-α, NF-κB p65, p-NF-κB p65, NLRP3, ASC, and Caspase1 in lung tissues (p < 0.05). Furthermore, NCTP could inhibit ileum histopathological injuries, restoring the ileum tight junctions by increasing the expression of ZO-1 and occludin. Simultaneously, NCTP could reverse the gut microbiota disorder, restore the diversity of gut microbiota, increase the relative abundance of Clostridiales and Lachnospiraceae, and enhance the content of SCFAs (acetic acid, propionic acid, and butyric acid) in feces. These results suggested that NCTP has preventive effects on septic ALI, and its mechanism is related to the regulation of gut microbiota, SCFA metabolism, and the TLR-4/NF-κB and NLRP3 pathways.


Assuntos
Lesão Pulmonar Aguda , Microbioma Gastrointestinal , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Polifenóis , Sepse , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/prevenção & controle , Lesão Pulmonar Aguda/microbiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 4 Toll-Like/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Polifenóis/farmacologia , Sepse/complicações , Sepse/metabolismo , Transdução de Sinais/efeitos dos fármacos , Masculino , Lipopolissacarídeos
3.
J Asian Nat Prod Res ; 26(7): 812-823, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38477295

RESUMO

Nineteen isosteviol derivatives were designed and synthesized by C-16, C-19 and D-ring modifications of isosteviol. These compounds were screened for their cytotoxic activities against Hela and A549 cells in vitro. Among them, the inhibitory effect of compounds 3b and 16 on Hela cells was comparable to that of the positive control gefitinib, and the compounds 3b (IC50=7.84 ± 0.84 µM) and 7a (IC50=6.89 ± 0.33 µM) exhibited significant cytotoxicity superior to gefitinib (IC50=11.02 ± 3.27 µM) against A549 cells.


Assuntos
Diterpenos do Tipo Caurano , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/química , Estrutura Molecular , Células HeLa , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Células A549 , Gefitinibe/farmacologia , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Quinazolinas/farmacologia , Quinazolinas/química , Quinazolinas/síntese química
5.
Ecol Evol ; 14(2): e10896, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38322009

RESUMO

The metacommunity theory proposes that community structure and biodiversity are influenced by both local processes (such as environmental filtering) and regional processes (such as dispersal). Despite the extensive use of traditional bioassessments based on species-environment relationships, the impact of dispersal processes on these assessments has been largely overlooked. This study aims to compare correlations between various bioassessment indices, including Shannon Weiner (H'), Biological Monitoring Working Party (BMWP), average score per taxon (ASPT), biotic index (BI), and EPT taxa index (EPT), based on macroinvertebrates collected from 147 sampling sites in a subtropical Chinese near-natural catchment. Modified indices were calculated by removing species strongly influenced by dispersal processes to address the influence of dispersal processes. Their relationship with environmental factors was then compared to the original indices. The study employed random forest regression (RFR) to compare the explanatory power of environmental factors using the two sets of indices. The spearman rank correlation analysis was conducted to examine the correlation between indices and environmental factors. The river health assessment was performed based on both modified and original indices. The results reveal significant differences between original and modified indices (especially H' and BI) providing a more accurate reflection of environmental conditions. Furthermore, the sensitivity of the different indices to various environmental factors varied, leading to differences in the bioassessment results between the modified and the original indices. Notably, original H', BMWP, and ASPT overestimated the bioassessment results, whereas the original BI underestimated them. These findings offer valuable insights into bioassessment and river health assessment evaluation within the catchment and other interconnected freshwater ecosystems, such as lakes, reservoirs, and wetlands. Our study underscores the importance of assessing and mitigating the impact of dispersal processes on bioassessment to obtain a more precise representation of the status of freshwater ecosystems.

6.
Heliyon ; 10(4): e26609, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404806

RESUMO

Objectives: To investigate the characteristics of brain structure in children with focal cortical dysplasia (FCD)-induced pharmacoresistant epilepsy, and explore the potential mechanisms of cognitive impairment from the view of gray matter alteration. Methods: 25 pharmacoresistant pediatric patients with pathologically confirmed focal cortical dysplasia (FCD), and 25 gender-matched healthy controls were included in this study. 3.0T MRI data and intelligence tests using the Wechsler Intelligence Scale for Children-Forth Edition (WISC-IV) were generated for all subjects. Voxel-based morphometry (VBM)-diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL) and surface-based morphometry (SBM) analyses were performed to analyze gray matter volume and cortical structure. Two-sample t-tests were used to compare the differences in gray matter volume (P<0.05, FWE) and cortical thickness (P<0.001, FWE) between the two groups. Also, the Spearman rank correlation analyses were employed to determine the relationship between structural alterations and neuropsychological results. Results: The WISC-IV scores of the FCD group were significantly lower than those of the HC group in terms of full-scale intelligence quotient (FSIQ), verbal comprehension index (VCI), perceptual reasoning index (PRI), working memory index (WMI), and processing speed index (PSI) (all P<0.01). Compared with the HC group, in the FCD group, the gray matter volume (GMV) reduced significantly in the left cerebellum_8, cerebellum_Crus2, and bilateral thalamus (P<0.05, FWE); the GMV increased in the bilateral medial frontal gyrus, right precuneus, and left inferior temporal gyrus (P<0.05, FWE), and the cortical thickness increased in the bilateral frontal, parietal, and temporal areas (P<0.001, FWE). Correlation analyses showed that the age of seizure onset had positive correlations with the WISC-IV scores significantly. Meanwhile, the cortex thicknesses of the left pars opercularis gyrus, left middle temporal gyrus, and right inferior temporal gyrus had negative correlations with the WISC-IV scores significantly. Conclusion: FCD patients showed subtle structural abnormalities in multiple brain regions, with significant involvement of the primary visual cortex and language function cortex. And we also demonstrated a crucial correlation between gray matter structural alteration and cognitive impairment.

7.
Pediatr Neurol ; 153: 116-124, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367486

RESUMO

BACKGROUND: Infantile epileptic spasms syndrome (IESS) would accompany with severe neurological impairment. Our study aimed to explore the potential mechanism by employing voxel-based and surface-based morphometry to detect brain microwould accompany with severe neurological impairment. Our study aimed to explore the potential mechanism by employing voxel-based and surface-based morphometry to detect brain microanatomic structure alteration. METHODS: The IESS group had 21 males and 13 females (mean age: 17.7 ± 15.6 months), whereas the healthy controls group had 22 males and 10 females (mean age: 29.4 ± 18.7 months). High-resolution 3D T1WI was performed. Computational Anatomy Toolbox implemented in Statistical Parametric Mapping 12 was used to measure the gray matter and white matter volume, and the cortical thickness separately. Independent sample t test was used to assess between-group differences. IESS group was assessed using the Bayley Scales of Infant Development. RESULTS: The IESS group showed a significantly decreased volume of gray matter in right middle temporal gyrus, inferior temporal gyrus, superior temporal gyrus, right fusiform, and bilateral precuneus (P < 0.001). There were no significant between-group differences with respect to white matter volume or cortical thickness (P > 0.001). The results of Bayley Scales of Infant Development showed that the Mental Development Index (MDI) and Psychomotor Development Index scores of children with IESS were almost concentrated in the range of <70. MDI score showed a positive correlation with gray matter reduction area in IESS group. CONCLUSION: Children with IESS had impaired cognitive and delayed motor development. And the decreased gray matter in the right temporal lobe, fusiform, and bilateral precuneus could be the potential anatomic basis for impaired function, such as hearing, visual, and language.


Assuntos
Espasmos Infantis , Substância Branca , Masculino , Criança , Lactente , Feminino , Humanos , Pré-Escolar , Espasmos Infantis/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Síndrome , Imageamento por Ressonância Magnética/métodos , Espasmo
8.
Acta Biochim Biophys Sin (Shanghai) ; 56(1): 106-113, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38151997

RESUMO

The regulation of various types of cell death may help to restore the normal physiological function of cells and play a protective role in sepsis. In the current study, we explore the role of programmed cell necrosis in sepsis and the underlying mechanisms. The septic rat model is established by Cecal-ligation and perforation (CLP), and the in vitro model is established by LPS in IEC-6 cells. Our results demonstrate that receptor-interacting protein 1 (RIP1) is significantly upregulated in the ileum of septic rats and LPS-treated IEC-6 cells at both the mRNA and protein levels. Nec-1, an inhibitor of RIP1, reduces the protein levels of RIP1, p-RIP3, and phosphorylated mixed-lineage kinase domain-like (MLKL) (serine 358) and relieves intestinal injury in CLP-induced septic rats with decreased IL-6 and TNF-α levels. The in vitro experiments further reveal that LPS induces the colocalization of RIP1 and RIP3, resulting in the phosphorylation and translocation of MLKL to the plasma membrane in IEC-6 cells. LPS also facilitates ROS production in IEC-6 cells, but this effect is further reversed by Nec-1, si-RIP1 and si-RIP3. Furthermore, LPS-induced necrosis in IEC-6 cells is counteracted by NAC. Thus, we conclude that RIP1/RIP3-dependent programmed cell necrosis participates in intestinal injury in sepsis and may be associated with RIP1/RIP3-mediated ROS.


Assuntos
Lipopolissacarídeos , Sepse , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Lipopolissacarídeos/toxicidade , Necrose/metabolismo , Apoptose , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Sepse/complicações
9.
Sci Rep ; 13(1): 19550, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945746

RESUMO

China has became the world's second largest pharmaceutical market, and the number of her registered clinical trials exceeded 3000 in 2021. Although thousands of healthy volunteers are participating in a large number of clinical trials in this country, there is no report about the characteristics, recognition, attitude of Chinese healthy volunteers and their concerns of clinical trials. A questionnaire survey was designed and given to 324 healthy volunteers participating in clinical trials in Wuhan, China. Four important findings emerged from our data. First, young, single and less educated men constituted the majority of Chinese healthy volunteers. Second, differences between the male and female healthy volunteers were observed. Female healthy volunteers are supposed to face more challenges and pressure in life, be more cautious about the clinical trials and more concerned about their health and feelings than the male. Third, no sociodemographic characteristic was associated with poorly understanding of the protocol research content, which was subjectively evaluated. Fourth, more support from society/family and more positive media reports about the participation of healthy volunteers in clinical trials are badly needed. These findings would help us to get a better understanding of Chinese healthy volunteers as a group for protecting them and promoting drug development.


Assuntos
Atitude , Emoções , Feminino , Humanos , Masculino , China , Voluntários Saudáveis , Inquéritos e Questionários , Ensaios Clínicos como Assunto
10.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(11): 1157-1163, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37987125

RESUMO

OBJECTIVE: To summarize clinical predictors and imaging characteristics of critically ill children infected with SARS-CoV-2 Omicron with neurological complications in Shenzhen during the peak of the first round of infections. METHODS: The clinical data of 11 critically ill children with neurological complications infected with SARS-CoV-2 Omicron in Shenzhen Children's Hospital from December 12 to 31, 2022, were retrospectively collected and analyzed. Laboratory test results related to liver parenchymal injury, histiocytic injury, inflammation, and coagulation function were collected, and imaging characteristics including CT and/or magnetic resonance imaging (MRI) were analyzed. The differences in CT/MRI score, acute necrotizing encephalopathy severity scale (ANE-SS) score and total score (CT/MRI score + ANE-SS score) were compared between the two groups with different prognosis during hospitation. RESULTS: Among 11 children, 7 were male and 4 were female. The age ranged from 10 months to 16 years. There were 5 cases of acute necrotizing encephalopathy (ANE) and 6 cases of acute fulminant cerebral edema (AFCE). During hospitalization, 3 patients survived and 8 patients died of multiple organ dysfunction syndrome (MODS), including 2 cases of ANE and 6 cases of AFCE. All cases had fever (> 38.5 centigrade), and 3 cases had ultra-high fever (> 41 centigrade). Within 48 hours of onset, all cases had disorders of consciousness and 9 cases had seizures. The 8 dead children had complications with multisystem involvement, including shock, respiratory failure, disseminated intravascular coagulation (DIC), liver failure, renal failure or myocardial damage, and the laboratory predictors related to hepatocellular injury [alanine aminotransferase (ALT), aspartate aminotransferase (AST)], histocyte injury [creatine kinase (CK), lactate dehydrogenase (LDH)], inflammation [procalcitonin (PCT), interleukin-6 (IL-6), serum ferritin (SF)], coagulation function (D-dimer) and blood glucose (Glu) increased in different quantities, of which PCT was specifically increased in 6 cases with AFCE, PLT was specifically decreased in 3 cases with AFCE, and ALT and LDH were significantly increased in 2 cases with ANE. Imaging analysis showed subarachnoid hemorrhage, basal ganglia and thalamus lesions in all 6 cases with AFCE, while thalamus lesions in all 5 cases with ANE. The ANE-SS score of 8 deceased children ranged from 2 to 7 (of which 6 cases were ≥ 5), and the ANE-SS score of 3 surviving children ranged from 0 to 2. Eight dead children had a CT/MRI score of 1-4 (of which 6 cases were 4), and 3 surviving children had a CT/MRI score of 1-2 (of which 2 cases were 1). The total score of 8 deceased children was 6-10 (of which 6 cases ≥ 8), and 3 surviving children was 1-4. CONCLUSIONS: The neurological complications of critically ill children infected with SARS-CoV-2 Omicron in Shenzhen progressed rapidly to ANE and AFCE, with high mortality. High fever (> 40 centigrade), convulsion/disturbance of consciousness, and multiple organ failure were the most common symptoms in ANE and AFCE cases. PCT increased and PLT decreased specifically in AFCE cases. Poor prognosis (death) was more common in age < 4 years old, predictors of ALT, AST, CK, LDH, PCT, D-dimer, Glu, IL-6 increased significantly, PLT decreased significantly. The common imaging feature of ANE and AFCE is the involvement of dorsal thalamus, a new imaging sign of AFCE (subarachnoid hemorrhage) was found. The higher the ANE-SS score, CT/MRI score and total score, the greater the risk of death.


Assuntos
Encefalopatias , COVID-19 , Humanos , Masculino , Criança , Feminino , Lactente , Pré-Escolar , SARS-CoV-2 , Interleucina-6 , Estudos Retrospectivos , Estado Terminal , COVID-19/complicações , Pró-Calcitonina , Inflamação , Encefalopatias/diagnóstico por imagem
11.
J Immunol Res ; 2023: 5577850, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781475

RESUMO

There remains a lack of standard models that have all the characteristics of human diseases. Especially in immunological hepatic fibrosis, the bovine serum albumin (BSA)-induced liver fibrosis models have the same developmental mechanisms as human liver fibrosis models, but have received little attention. We standardized a BSA-induced liver fibrosis model in rats and thoroughly assessed its pathological characteristics. We also used 16S sequencing to assess homeostasis of the intestinal microflora of rats with BSA-induced liver fibrosis and detected various differential metabolites in the serum of these rats using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). We observed stable and unambiguous histological changes in liver tissue morphology and remarkably high concentrations of inflammatory markers in the serum of BSA-induced liver fibrosis rats. In keeping with the fact that BSA induction can cause gut microbiota disorders in rats. UHPLC-MS/MS analysis of rat serum samples in positive-ion mode and negative-ion mode revealed 17 and 25 differential metabolites, respectively. Network analysis revealed that phenylalanine or tyrosine metabolites (e.g., PAGln) were the predominant metabolites in the sera of BSA-induced liver fibrosis rats. Taken together, our results suggest that disorders of amino acid metabolism caused by the gut microbiota may play an important role in the progression of immunological hepatic fibrosis.


Assuntos
Cirrose Hepática , Espectrometria de Massas em Tandem , Ratos , Humanos , Animais , Espectrometria de Massas em Tandem/métodos , Cirrose Hepática/patologia , Metaboloma , Cromatografia Líquida de Alta Pressão/métodos
12.
Environ Pollut ; 337: 122574, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37722474

RESUMO

Polyvinyl alcohol (PVA) has been widely used as a water-soluble plastic in laundry and dish detergent pods, yet wastewater contaminated with PVA is too difficult to be treated due to its high salinity and foaming. Here, we fabricated blast furnace dust (BFD) particle electrodes, and developed a three-dimensional electrocatalytic system (3DEC) to treat saline PVA wastewater. The optimum preparation condition for BFD particle electrode was iron carbon ratio of 2:1 doping with TiO2. The optimal parameters of 3DECs for PVA wastewater degradation were thoroughly investigated, with current density of 30 mA/cm2, electrode distance of 30 mm, pH value of 7.0, and particle electrode filling rate of 50%. PVA wastewater degradation rate could reach 89.33% within 120 min. The underlying mechanism of iron-carbon micro electrolysis and electrocatalytic system was further studied. PVA wastewater was degraded by direct catalytic oxidation from electrodes. A scavenger experiment showed that free radicals consisting of •OH and HClO mainly contributed to the PVA wastewater degradation. HClO was generated by Cl- at the electrocatalysis and micro electrolysis of particles. In addition, the lifetime of the prepared BFD particle electrode was 120 h, which exhibited electrochemical stability. These findings highlight that the 3DECs coupled with BFD particle electrode is a promising electrocatalysis process for the removal of PVA wastewater.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Álcool de Polivinil , Poluentes Químicos da Água/análise , Oxirredução , Carbono , Eletrodos , Ferro
13.
Org Biomol Chem ; 21(30): 6107-6110, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37461849

RESUMO

A straightforward and efficient approach for the synthesis of carbamoyl-substituted oxindoles has been developed via a palladium-catalyzed Heck cyclization and reductive aminocarbonylation reaction of alkene-tethered carbamoyl chlorides with nitro compounds. The reaction showed good compatibility toward versatile functional groups, and both nitroarenes and nitroalkanes were well tolerated. Using Mo(CO)6 as a solid CO source, without external reductants, a broad range of carbamoyl-substituted oxindoles were obtained in moderate to high yields.

14.
Org Lett ; 25(22): 4140-4144, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37227073

RESUMO

A palladium-catalyzed thiocarbonylation reaction for the synthesis of α,ß-unsaturated thioesters from vinyl triflates with S-aryl thioformates as the thioester sources has been developed. The reaction proceeded smoothly at low temperature, and a variety of α,ß-unsaturated thioesters were produced in moderate to high yields with very good functional group tolerance. This protocol features mild reaction conditions, good substrate scope, and avoids the use of toxic CO gas or odorous thiols, which made it a worthy addition to α,ß-unsaturated thioester synthesis via a thioester transfer process.


Assuntos
Paládio , Compostos de Sulfidrila , Catálise
15.
Artigo em Inglês | MEDLINE | ID: mdl-36532852

RESUMO

An effectual remedy for hepatocellular carcinoma (HCC) and knowledge of the mechanism are urgently needed. Researchers have found that CPhGs, an extract from Cistanche tubulosa (Schenk) Wight, had better antitumor effects, but its mechanism is still unknown. In the present study, using an H22 tumor-bearing mouse as a model, we investigated the antitumor effects of CPhGs and the effect of CPhGs on autophagy and apoptosis. Besides, we also discussed the role of autophagy with the help of HCQ and rapamycin. Our results show that CPhGs inhibit tumor growth and induce apoptosis and autophagy of tumor tissue. TUNEL staining displayed that tumor apoptosis rate increased after the intervention of CPhGs, and immunohistochemistry and western blot showed that cleaved-PARP and cleaved-caspase 3 were upregulated after the intervention of CPhGs, and these results were most pronounced in the high-dose group. Autophagy results revealed that CPhGs increased the number of autophagosomes, increased the level of LC3B-II, and decreased the level of p62. Finally, our results showed that excessive autophagy suppresses tumor growth, whereas inhibition of autophagy does the opposite, which indicated that CPhGs induced autophagic death in H22 hepatoma-bearing mice. These data altogether confirmed the involvement of apoptosis and autophagy in CPhGs treatment for HCC.

16.
Org Lett ; 24(35): 6477-6482, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36040811

RESUMO

A novel and straightforward methodology for palladium-catalyzed carbopalladation-initiated domino carbonylative cyclization to construct bisheterocycles has been established. With TFBen as an efficient and convenient CO source, the protocol is capable of generating oxindole and 3-acylbenzofuran/3-acylindole moieties from the corresponding N-(o-iodoaryl)acrylamides and o-alkynylphenols/o-alkynylanilines with the formation of three C-C bonds and one C-O/C-N bond in a single one-step operation. A wide range of bisheterocycles bearing oxindoles and 3-acylbenzofurans/3-acylindoles were prepared in moderate to excellent yields with good functional group tolerance.

17.
Org Lett ; 24(22): 4009-4013, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35613710

RESUMO

A straightforward and efficient synthesis of α,ß-unsaturated thioesters has been developed via a nickel-catalyzed thiocarbonylation reaction of vinyl triflates with arylsulfonyl chlorides. With Mo(CO)6 as both CO source and reductant, a variety of α,ß-unsaturated thioesters were obtained in moderate to good yields with very good functional group compatibility. It is noteworthy that the present method is the first example on nickel-catalyzed carbonylative synthesis of α,ß-unsaturated thioesters by using arylsulfonyl chlorides as the coupling partner.

18.
Org Lett ; 24(11): 2248-2252, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35271283

RESUMO

An attractive palladium-catalyzed reductive aminocarbonylation reaction of allylic ethers has been explored for the synthesis of 3-alkenylquinolin-2(1H)-one derivatives. With Mo(CO)6 as both CO surrogate and reductant, a variety of 3-alkenylquinolin-2(1H)-ones were obtained in good to excellent yields from o-iodophenol-derived allyl ethers with o-nitrobenzaldehydes as the nitrogen sources. This reaction proceeds through a cascade pathway and does not rely on high-pressure CO gas as needed in former allylic carbonylation reactions. This strategy provides a new pathway for the construction of 3-alkenylquinolin-2(1H)-ones.

19.
Org Biomol Chem ; 20(13): 2605-2608, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35293928

RESUMO

A palladium-catalyzed Heck/carbonylative cyclization process has been explored for the synthesis of functionalized amides. By using nitroarenes as readily accessible nitrogen sources, a variety of amide products were obtained in moderate to excellent yields with good functional group compatibility. Furthermore, a late-stage modification of a natural molecule is also achieved by this protocol.


Assuntos
Amidas , Paládio , Catálise , Ciclização
20.
J Org Chem ; 86(19): 13824-13832, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542996

RESUMO

A palladium-catalyzed straightforward procedure for the synthesis of 3-arylquinolin-2(1H)-ones has been developed. The synthesis proceeds through a palladium-catalyzed reductive aminocarbonylation reaction of benzylic ammonium triflates with o-nitrobenzaldehydes, and a wide range of 3-arylquinolin-2(1H)-ones was obtained in moderate to good yields with very good functional group compatibility.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA