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1.
iScience ; 26(9): 107485, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37636055

RESUMO

Smart wearable sensors are electronic devices worn on the body that collect, process, and transmit various physiological data. Compared to traditional devices, their advantages in terms of portability and comfort have made them increasingly important in the medical field. This review takes a unique clinical physician's standpoint, diverging from conventional sensor-type-based classifications, and provides a comprehensive overview of the diverse clinical applications of wearable sensors in recent years. In this review, we categorize these applications according to different diseases, encompassing skin diseases and injuries, cardiovascular diseases, abnormal human motion, as well as endocrine and metabolic disorders. Additionally, we discuss the challenges and perspectives hindering the development of sensors for clinical use, emphasizing the critical need for interdisciplinary collaboration between medical and engineering professionals. Overall, this review would serve as an important reference for the future direction of sensor devices in clinical use.

2.
J Invest Dermatol ; 143(5): 812-821.e3, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36410425

RESUMO

Type I cannabinoid receptor (CB1R) has been reported to exhibit favorable anti-inflammation and antipruritus effects against inflammation-based skin diseases, but the specific mechanism remains to be explored. In this study, we found that the activation of CB1R significantly relieved the scratching behavior and skin inflammation in a psoriatic mouse model, whereas CB1R antagonist aggravated these symptoms. Because the expression of CB1R was abundant in dorsal root ganglia, we constructed mice with conditional CB1R knockout in primary sensory neurons and found that imiquimod-induced psoriasiform inflammation and itch were both worsened in CB1R-conditional knockout mice. Next, we observed that the CB1R was mostly located in peptidergic neurons, and deletion of CB1R in primary sensory neurons promoted the production and release of substance P to the skin tissue. Furthermore, the elevated substance P in the skin affected the activation of extracellular signal‒regulated kinase in keratinocytes and induced the accumulation of mast cells in the dermis. Finally, we showed that blocking the substance P signal significantly alleviated the exacerbation of psoriasiform inflammation and itch caused by imiquimod in CB1R-conditional knockout mice. Together, our work reveals that CB1R in sensory neurons plays a key role in psoriasiform skin inflammation and pruritus by regulating substance P expression.


Assuntos
Prurido , Psoríase , Receptor CB1 de Canabinoide , Células Receptoras Sensoriais , Prurido/induzido quimicamente , Prurido/metabolismo , Psoríase/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Células Receptoras Sensoriais/metabolismo , Anti-Inflamatórios/metabolismo , Antipruriginosos/metabolismo , Modelos Animais , Camundongos Knockout , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Substância P/metabolismo , Queratinócitos/metabolismo , Fosfotransferases/metabolismo , Pele/metabolismo
3.
Biomed Pharmacother ; 155: 113741, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36271543

RESUMO

Melanoma is the most lethal skin cancer with rising incidence worldwide. Despite significant advances in target therapy and immunotherapy, low response rates and the development of drug resistance remain key clinical barriers affecting patient prognosis. The complex interplay between multiple signaling molecules and pathways has brought little understanding of melanoma pathogenesis and resistance. The genetic mutation and hypermetabolic environment of melanoma cells lead to increasing demands for protein synthesis and perturb proteostasis resulting in endoplasmic reticulum (ER) stress. Subsequently, three unfolded protein response (UPR) signaling branches, represented by IRE1α, PERK and ATF6, are activated to direct cell fate towards pro-survival or pro-apoptosis depending on the intensity and duration of ER stress. In this review, we summarize ER stress and UPR in melanoma cells and tumor-infiltrating immune cells along with the crosstalk among these pathways. We provide the latest advances in understanding melanoma pathogenesis and resistance and discuss the potential of targeting the ER stress or UPR process for melanoma therapy.


Assuntos
Estresse do Retículo Endoplasmático , Melanoma , Humanos , Endorribonucleases/metabolismo , Proteínas Serina-Treonina Quinases , Apoptose/fisiologia , Melanoma/patologia
4.
Front Pharmacol ; 13: 790712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173615

RESUMO

Background: Cannabinoid receptor 2 (CB2R) is a potential target for anti-inflammatory and pain therapeutics given its significant immunomodulatory and analgesic effects. However, the role of CB2R in imiquimod (IMQ)-induced psoriasiform dermatitis (PsD) and itch is poorly understood. Objective: To investigate the function and mechanism of CB2R in PsD and itch in mice. Methods: Following daily treatment with topical IMQ cream for 5-7 consecutive days in C56BL/6 wild-type (WT) and CB2R gene knockout (KO) mice, we assessed the Psoriasis Area and Severity Index (PASI) scores and the scratch bouts every day, and hematoxylin and eosin (H&E) staining, toluidine blue staining were used to observe the histological changes. mRNA levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Protein levels were detected by western blotting (WB), immunohistochemistry (IHC), immunofluorescence (IF) and cytometric bead array (CBA). Flow cytometry (FCM) was used to examine the proportion of Th17/Treg cells. Results: We found that CB2R expression levels were increased in mice with psoriasis. Compared with WT mice, CB2R deficiency exacerbated IMQ-induced PsD and scratching bouts and upregulated the expression of proinflammatory cytokines by increasing the infiltration of CD4+ T cells and the Th17/Treg ratio. Obvious proliferation and prolongation of nerve fibers and high expression of nerve growth factor (NGF) were observed in PsD and CB2R KO mice. Pretreatment with the CB2R agonist, JWH-133 significantly reversed inflammation and scratching bouts. CB2R didn't participate in the induction of itch in psoriasis by regulating the expression of IL-31, thymic stromal lymphopoietin (TSLP) and mast cells in mouse skins. Conclusion: Our results demonstrate that CB2R plays a pivotal role in the pathophysiology of psoriasis, providing a new potential target for anti-inflammatory and antipruritic drugs.

5.
Front Immunol ; 13: 1094375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36700214

RESUMO

Introduction: Psoriasis is a common inflammatory skin disease recognized by the World Health Organization as "an incurable chronic, noninfectious, painful, disfiguring and disabling disease." The fact that metabolic syndrome (MetS) is the most common and important comorbidities of psoriasis suggests an important role of lipid metabolism in the pathogenesis of psoriasis. Narciclasine (Ncs) is an alkaloid isolated from the Amaryllidaceae plants. Its biological activities include antitumor, antibacterial, antiinflammatory, anti-angiogenic and promoting energy expenditure to improve dietinduced obesity. Here, we report that Ncs may be a potential candidate for psoriasis, acting at both the organismal and cellular levels. Methods: The therapeutic effect of Ncs was assessed in IMQ-induced psoriasis-like mouse model. Then, through in vitro experiments, we explored the inhibitory effect of Ncs on HaCaT cell proliferation and Th17 cell polarization; Transcriptomics and lipidomics were used to analyze the major targets of Ncs; Single-cell sequencing data was used to identify the target cells of Ncs action. Results: Ncs can inhibit keratinocyte proliferation and reduce the recruitment of immune cells in the skin by inhibiting psoriasis-associated inflammatory mediators. In addition, it showed a direct repression effect on Th17 cell polarization. Transcriptomic and lipidomic data further revealed that Ncs extensively regulated lipid metabolismrelated genes, especially the Phospholipase A2 (PLA2) family, and increased antiinflammatory lipid molecules. Combined with single-cell data analysis, we confirmed that keratinocytes are the main cells in which Ncs functions. Discussion: Taken together, our findings indicate that Ncs alleviates psoriasiform skin inflammation in mice, which is associated with inhibition of PLA2 in keratinocytes and improved phospholipid metabolism. Ncs has the potential for further development as a novel anti-psoriasis drug.


Assuntos
Dermatite , Fosfolipases A2 do Grupo IV , Psoríase , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Dermatite/tratamento farmacológico , Fosfolipases A2 do Grupo IV/antagonistas & inibidores , Imiquimode/efeitos adversos , Metabolismo dos Lipídeos , Fosfolipídeos , Psoríase/tratamento farmacológico
6.
Adv Healthc Mater ; 10(3): e2001463, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33274856

RESUMO

Ultrasound-driven sonodynamic therapy (SDT) catches numerous attentions for destroying deep-seated tumors, but its applications suffer from unsatisfactory therapeutic effects and metabolism. Furthermore, SDT is usually weakened by the complex tumor microenvironment, such as the overexpression of glutathione (GSH). To address these issues, Mn(III)-hemoporfin frameworks (Mn(III)-HFs) are reported as nanosonosensitizers by using biocompatible hematoporphyrin monomethyl-ether (HMME) to coordinate with Mn(III) ions. Mn(III)-HFs/PEG can react with GSH to produce Mn(II) ions and oxidized glutathione (GSSG), resulting in three fascinating features: 1) the redox reaction facilitates the decomposition of Mn(III)-HFs/PEG and then collapse of nanostructures, improving the biodegradability; 2) Mn(II) ions with five unpaired 3d-electrons exhibit better magnetic resonance imaging (MRI) ability compared to Mn(III) ions with four electrons; 3) both the depletion of endogenous GSH and the dissociated HMME boost 1 O2 generation ability under US irradiation. As a result, when Mn(III)-HFs/PEG dispersion is intravenously administered into mice, it exhibits high-contrast T1 /T2 dual-modal MRI and significant suppression for the growth rate of the deep-seated tumor. Furthermore, Mn(III)-HFs/PEG can be efficiently metabolized from the mice. Therefore, Mn(III)-HFs/PEG exhibit GSH-enhanced degradation, MRI, and SDT effects, which provide some insights on the developments of other responsive nanosonosensitizers.


Assuntos
Hematoporfirinas , Imageamento por Ressonância Magnética , Neoplasias/terapia , Animais , Glutationa , Camundongos
7.
Front Genet ; 11: 1002, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33005180

RESUMO

Melanoma is the leading cause of cancer-related death among skin tumors, with an increasing incidence worldwide. Few studies have effectively investigated the significance of an immune-related gene (IRG) signature for melanoma prognosis. Here, we constructed an IRGs prognostic signature using bioinformatics methods and evaluated and validated its predictive capability. Then, immune cell infiltration and tumor mutation burden (TMB) landscapes associated with this signature in melanoma were analyzed comprehensively. With the 10-IRG prognostic signature, melanoma patients in the low-risk group showed better survival with distinct features of high immune cell infiltration and TMB. Importantly, melanoma patients in this subgroup were significantly responsive to MAGE-A3 in the validation cohort. This immune-related prognostic signature is thus a reliable tool to predict melanoma prognosis; as the underlying mechanism of this signature is associated with immune infiltration and mutation burden, it might reflect the benefit of immunotherapy to patients.

8.
Am J Emerg Med ; 38(12): 2681-2692, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046314

RESUMO

BACKGROUND: Blood-activating drugs (BADs) are widely used to treat microvascular angina in China. This study aims to summarize relevant evidence from randomized controlled trials (RCTs) to assess the efficacy and safety of BADs in the treatment of microvascular angina. METHODS: We searched for relevant studies before June 2019 from seven databases. Twenty-four studies were included of 1903 patients with microvascular angina. All studies compared the use of traditional Chinese medicine for activating blood circulation (BADs) and Western medicine (WM) with the use of Western medicine alone. RESULTS: In all, 15 trials reported a significant effect of BADs on improving clinical symptoms compared with the control treatment (P < .00001), and 8 trials reported significant effects of BADs on reducing the frequency of angina pectoris attacks compared with Western medicine treatment (P < .00001). The pooled results also demonstrated that BADs provided a significant benefit in reducing the dosage of nitroglycerin required (P = .02), the maximum range of ST-segment depression (P = .003) and the descending degree of the ST-T segment of ECG (P = .0002); prolonging the total time of treadmill exercise (P < .00001) and the time of ST-segment depression of 1 mm (P = .002); enhancing the total effective rate of Traditional Chinese Medicine (TCM) syndromes (P < .00001); improving endothelial function (P < .00001); and reducing the levels of high-sensitivity C-reactive protein (hs-CRP) (P < .00001). BAD treatment showed no statistically significant effect on the levels of TNF-a (P = .8) or IL-6 (P = .13). No severe adverse events were reported. CONCLUSION: This meta-analysis shows that BADs are effective for the treatment of microvascular angina. Although concerns regarding selective bias and low methodological quality were raised, our findings suggest that BADs are beneficial for patients with microvascular angina and should be given priority for future clinical studies.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Angina Microvascular/tratamento farmacológico , Proteína C-Reativa/metabolismo , Endotelina-1/metabolismo , Teste de Esforço , Humanos , Interleucina-6/metabolismo , Medicina Tradicional Chinesa , Angina Microvascular/metabolismo , Angina Microvascular/fisiopatologia , Óxido Nítrico/metabolismo , Nitroglicerina/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo , Vasodilatadores/administração & dosagem
9.
Mol Med Rep ; 21(4): 1941-1949, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32319620

RESUMO

DNA methylation and hydroxymethylation are the most common epigenetic modifications associated with the cell cycle and the inflammatory response. The present study aimed to investigate the role of 5­hydroxymethyl­cytosine (5­hmC) and ten­eleven translocation­2 (TET2) in keratinocytes. Following TET2 knockdown, dot blot analysis was performed to assess the levels of 5­hmC in keratinocytes, using HaCaT cells. Subsequently, the viability and cell cycle of HaCaT cells were assessed by MTT, Cell Counting Kit­8 assay and flow cytometric assays. Cyclin­dependent kinase inhibitor 2A and proinflammatory cytokine protein and mRNA expression levels were also detected. The present results suggested that TET2 may play an important role in regulating cellular proliferation by mediating DNA hydroxymethylation in HaCaT cells. In addition, TET2 knockdown decreased the production of proinflammatory cytokines, including lipocalin 2, S100 calcium binding protein A7, matrix metallopeptidase 9, C­X­C motif chemokine ligand 1, interferon regulatory factor 7 and interleukin­7 receptor. The present study suggested that TET2 regulated cell viability, apoptosis and the expression of inflammatory mediators in keratinocytes. Collectively, the results indicated that TET2 knockdown may relieve inflammatory responses in the skin.


Assuntos
Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inflamação/genética , Queratinócitos/metabolismo , Queratinócitos/patologia , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Apoptose/genética , Ciclo Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dioxigenases , Células HaCaT , Humanos , Mediadores da Inflamação/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Am J Emerg Med ; 38(6): 1218-1225, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32107129

RESUMO

BACKGROUND: Kuanxiong Aerosol (KA) has been used in patients with angina pectoris (AP) attacks for many years, this systematic review and meta-analysis aims to evaluate the clinical efficacy and safety of KA versus nitrates in the treatment of AP. METHODS: Seven databases (PubMed, EMBASE, CENTRAL, CNKI, VIP, CBM and Wanfang) were searched from inception to November 2019 to include randomized controlled trials (RCTs) that compare the efficacy and safety of KA with nitrates on the treatment of AP. And two reviewers independently assessed the risk of bias. RESULT: A total of 12 RCTs were eventually included, involving 2001 patients. Compared with the Nitrates group, the KA group showed great significant improvement on the 3-min [relative risk (RR) = 1.12, 95% confidence interval (CI) (1.03,1.23), P < .05;11 studies,1875 patients] and 5-min [RR = 1.05, 95%CI (1.01,1.08), P < 0.05; 11 studies,1875 patients] angina remission rates, the incidence of adverse reactions [RR = 0.42,95% CI (0.33,0.54), P < 0.00001; 8 studies, 1350 patients], endothelin(ET) [SMD = -0.40, 95%CI (-0.74,-0.07), P < 0.05; 2 studies, 143 patients] and c-reactive protein (CRP) [SMD = -0.58, 95%CI (-0.87,-0.30), P < 0.00001;2 studies, 200 patients],but no significant improvement on electrocardiogram efficacy [RR = 1.03, 95%CI (0.98,1.10), P = 0.26;11 studies, 1549 patients], nitric oxide (NO) [SMD = -0.08, 95%CI (-0.61,0.45), P = 0.76;2 studies, 143 patients]. CONCLUSION: The clinical use of KA is effective and safe on the treatment of AP, which appears to be better than nitrates in terms of efficiency, adverse reactions, endothelial function and inflammatory response. Nevertheless, due to some limitations in the sample size and quality of the included studies, more high-quality RCTs were still needed for further verification.


Assuntos
Angina Pectoris/tratamento farmacológico , Óleos Voláteis/uso terapêutico , Combinação de Medicamentos , Humanos , Nitratos/normas , Nitratos/uso terapêutico , Óleos Voláteis/normas , Extratos Vegetais/normas , Extratos Vegetais/uso terapêutico , Resultado do Tratamento
11.
Cell Death Dis ; 11(2): 134, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075957

RESUMO

Psoriasis is a common autoimmune and chronic inflammatory skin disorder globally affecting 0.51-11.43% of adults. Inflammation-associated cell death in keratinocytes plays a key role in the process of integrate inflammatory cascade in psoriasis. Necroptosis is a regulated necrotic cell death mediated by receptor interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like pseudokinase (MLKL), which participates in many human inflammatory diseases. However, the mechanism and function of programmed necrosis in psoriasis is not well-illustrated. In the current study, we provide evidence for the involvement of necroptosis in psoriasis. RIPK1 and MLKL were significantly upregulated and localized in all layers of the epidermis in human psoriatic lesions, while RIPK3 and phosphorylated MLKL were mainly expressed in keratinocytes, which located in the upper layers. Increased tendency of necroptosis was also found in IMQ-induced psoriasiform skin of mice. Further, we discovered that both the inhibitor of RIPK1 R-7-Cl-O-Necrostatin-1 (Nec-1s) and MLKL-inhibitor necrosulfonamide (NSA) suppressed necroptosis in HaCaT cells and IMQ mouse models, powerfully blocked IMQ-induced inflammatory responses in vivo, and significantly downregulated the production of inflammatory factors like IL-1ß, IL-6, IL-17A, IL-23a, CXCL1, and CCL20. These findings promote the development of new therapies for the treatment of necroptosis-activated pathologies for psoriasis.


Assuntos
Anti-Inflamatórios/farmacologia , Queratinócitos/efeitos dos fármacos , Necroptose/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Psoríase/prevenção & controle , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Pele/efeitos dos fármacos , Acrilamidas/farmacologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células HaCaT , Humanos , Imidazóis/farmacologia , Imiquimode , Indóis/farmacologia , Mediadores da Inflamação/metabolismo , Queratinócitos/enzimologia , Queratinócitos/patologia , Camundongos Endogâmicos BALB C , Fosforilação , Psoríase/induzido quimicamente , Psoríase/enzimologia , Psoríase/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Pele/enzimologia , Pele/patologia , Sulfonamidas/farmacologia
12.
Medicine (Baltimore) ; 97(51): e13692, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30572496

RESUMO

BACKGROUND: Chronic heart failure (CHF) is one of the most important cardiovascular diseases worldly, with high morbidity and mortality. Fuling Sini decoction (FSD) has been used in the management of CHF widely in China, while its effective evidence is not clear. A systematic review and meta-analysis to evaluate FSD for CHF is lacking. Hence, we propose a protocol for systematic evaluation of its efficacy and safety for CHF. METHODS: We will search the following electronic databases from inception to October 2018, including EMBASE, Cochrane Center Registration Controlled trials (Cochrane Library), PubMed, Medline, WHO International Clinical Trials Registry Platform, China Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), and Wan-fang database. Only randomized controlled trials (RCTs) of FSD alone or combined with other management for CHF will be included. Two independent reviewers will screen the literature and extract data according to the Cochrane Handbook method. The assessment of bias risk, data synthesis, subgroup analysis, and meta-analyses and finally meta-analysis will be performed by using RevMan V.5.3.5 software. RESULTS: This systematic review will provide high-quality evidence and may be the first to evaluate efficacy and safety of FSD in the treatment of CHF. CONCLUSION: This systematic review will provide evidence for judging whether FSD is an effective management for CHF or not. PROSPERO REGISTRATION NUMBER: CRD 42018110210.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Wolfiporia , Humanos , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Medicina Tradicional Chinesa , Fitoterapia/efeitos adversos , Metanálise como Assunto , Revisões Sistemáticas como Assunto
13.
Org Biomol Chem ; 16(45): 8719-8723, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30191227

RESUMO

A one-pot protocol of double Suzuki-Miyaura reactions has been developed for the synthesis of unsymmetrical terphenyls. In the absence of a ligand, potassium bromophenyltrifluoroborate reacts with arylboronic acid and then sequentially with a hetero/aryl bromide by controlling the reaction temperature, providing unsymmetrical p- and m-terphenyl compounds in moderate to good overall yields. This protocol provides a convenient and practical approach to unsymmetrical terphenyls under ligand-free and aerobic conditions.

14.
Dalton Trans ; 45(2): 734-41, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26630292

RESUMO

Three bis-cyclometalated cationic Ir(iii) complexes , and with an ester substituent at the 4-position of the phenyl ring on the 2-phenylpyridine (ppy) have been synthesized and fully characterized. The emission maxima of ester-substituted Ir(iii) complexes show a notable blue-shift compared to the parent complex [Ir(ppy)2(phen)](+)PF6(-) (phen = 1,10-phenanthroline). The influence of an ester group on the photoelectric properties of the Ir(iii) complexes has been investigated systematically. The oxygen sensing films prepared from ethyl cellulose immobilized with Ir(iii) complexes exhibit excellent operational stability, high photostability and a quick response to oxygen. show extended luminescence lifetimes relative to , and display better sensitivity to changes in oxygen partial pressure.

15.
J Nanosci Nanotechnol ; 13(7): 5048-52, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23901529

RESUMO

Thermoregulated ionic liquid and organic biphasic system composed of ionic liquid [CH3(OCH2 CH2)22N+Et3][CH3SO3-] (abbreviated as IL(PEG1000)) containing IL(PEG1000)-stabilized Rh nanoparticles and organic solvent, which allows for not only highly efficient homogeneous reaction but also an easy biphasic separation, was applied to the hydroaminomethylation of 1-octene for the first time. Under the optimized conditions, the conversion of 1-octene and the amine selectivity were 100% and 90%, respectively. After reaction, the Rh nanoparticle catalyst could be easily separated by simple decantation and reused for four times without evident loss in activity.


Assuntos
Alcenos/química , Líquidos Iônicos/química , Nanopartículas Metálicas/química , Compostos Orgânicos/química , Ródio/química , Catálise , Teste de Materiais , Transição de Fase , Temperatura
16.
Org Biomol Chem ; 10(39): 7875-83, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22890246

RESUMO

A palladium-catalyzed aerobic and ligand-free Suzuki reaction in aqueous ethanol has been developed for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives. A number of N-heteroaryl halides, namely 2-halogenated pyridines, 2-bromoquinoline, 5-bromopyrimidine and 2-chloropyrazine, were coupled with 4-(9H-carbazol-9-yl)phenylboronic acid (CPBA) or 9-phenyl-9H-carbazol-3-ylboronic acid (PCBA) efficiently to afford good to excellent yields in a short reaction time. Moreover, the catalytic system of Pd(OAc)(2)-EtOH/H(2)O-K(2)CO(3) was successfully extended to the cross-couplings of N-heteroaryl halides with various arylboronic acids. The results demonstrated that the cross-coupling reaction in the present protocol was promoted by oxygen.


Assuntos
Carbazóis/síntese química , Compostos Organometálicos/química , Paládio/química , Carbazóis/química , Catálise , Estrutura Molecular
17.
Org Lett ; 9(20): 4005-7, 2007 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-17760456

RESUMO

An oxygen-promoted ligand-free Suzuki coupling reaction catalyzed by in situ generated palladium nanoparticles in PEG-400 under aerobic conditions has been demonstrated. The reaction was highly efficient for coupling aryl chlorides with phenylboronic acid in short times under mild conditions.


Assuntos
Cloretos/química , Nanopartículas Metálicas/química , Oxigênio/química , Paládio/química , Ácidos Borônicos/química , Ligantes , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Polietilenoglicóis
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