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1.
Eur J Med Res ; 29(1): 183, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500195

RESUMO

BACKGROUND: Renal fibrosis (RF) produced adverse effect on kidney function. Recently, intestinal dysbiosis is a key regulator that promotes the formation of renal fibrosis. This study will focus on exploring the protective mechanism of Kangxianling Formula (KXL) on renal fibrosis from the perspective of intestinal flora. METHODS: Unilateral Ureteral Obstruction (UUO) was used to construct rats' model with RF, and receive KXL formula intervention for 1 week. The renal function indicators were measured. Hematoxylin-eosin (HE), Masson and Sirus red staining were employed to detect the pathological changes of renal tissue in each group. The expression of α-SMA, Col-III, TGF-ß, FN, ZO-1, and Occuludin was detected by immunofluorescence and immunohistochemistry. Rat feces samples were collected and analyzed for species' diversity using high-throughput sequencing 16S rRNA. RESULTS: Rats in UUO groups displayed poor renal function as well as severe RF. The pro-fibrotic protein expression in renal tissues including α-SMA, Col-III, TGF-ß and FN was increased in UUO rats, while ZO-1 and Occuludin -1 expression was downregulated in colon tissues. The above changes were attenuated by KXL treatment. 16S rRNA sequencing results revealed that compared with the sham group, the increased abundance of pathogenic bacteria including Acinetobacter, Enterobacter and Proteobacteria and the decreased abundance of beneficial bacteria including Actinobacteriota, Bifidobacteriales, Prevotellaceae, and Lactobacillus were found in UUO group. After the administration of KXL, the growth of potential pathogenic bacteria was reduced and the abundance of beneficial bacteria was enhanced. CONCLUSION: KXL displays a therapeutical potential in protecting renal function and inhibiting RF, and its mechanism of action may be associated with regulating intestinal microbiota.


Assuntos
Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Nefropatias , Obstrução Ureteral , Ratos , Animais , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Ratos Sprague-Dawley , Nefropatias/tratamento farmacológico , Nefropatias/metabolismo , Rim/patologia , Obstrução Ureteral/complicações , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fibrose , Fator de Crescimento Transformador beta1
2.
Front Biosci (Landmark Ed) ; 29(2): 58, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38420829

RESUMO

BACKGROUND: Pyroptosis is a critical form of cell death during the development of chronic kidney disease (CKD). Tripartite motif 6 (TRIM6) is an E3-ubiquitin ligase that participates in the progression renal fibrosis (RF). The aim of this study was to investigate the roles of TRIM6 and Glutathione peroxidase 3 (GPX3) in oxidative stress-induced inflammasome activation and pyroptosis in Ang-II treated renal tubular epithelial cells. METHODS: To study its role in RF, TRIM6 expression was either reduced or increased in human kidney-2 (HK2) cells using lentivirus, and Ang-II, NAC and BMS-986299 were served as reactive oxygen species (ROS) inducer, ROS scavenger and NLRP3 agonist respectively. Pyroptosis and mitochondrial ROS were measured by flow cytometry. The levels of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were determined using commercial kits, while the levels of IL-1ß, IL-18, IL-6, and tumor necrosis factor-α (TNF-α) were determined by Enzyme-Linked Immunosorbent Assay (ELISA). Co-immunoprecipitation (Co-IP) assay was used to evaluate the interaction between TRIM6 and GPX3. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot were used to measure mRNA and protein expression, respectively. RESULTS: Treatment with Angiotensin II (Ang II) increased the protein and mRNA levels of TRIM6 in HK2 cells. Ang II also increased mitochondrial ROS production and the malondialdehyde (MDA) level, but decreased the levels of GSH and SOD. In addition, Ang II enhanced HK2 cell pyroptosis, increased the levels of IL-1ß, IL-18, IL-6, and TNF-α, and promoted the expression of active IL-1ß, NLRP3, caspase-1, and GSDMD-N proteins. These effects were reversed by knockdown of TRIM6 and by treatment with N-acetyl-L-cysteine (NAC), a ROS scavenger. BMS-986299, an NLRP3 agonist treatment, did not affect ROS production in HK2 cells exposed to Ang II combined with NAC, but cell pyroptosis and inflammation were aggravated. Moreover, the overexpression of TRIM6 in HK2 cells resulted in similar effects to Ang II. NAC and GPX3 overexpression in HK2 cells could reverse ROS production, inflammation, and pyroptosis induced by TRIM6 overexpression. TRIM6 overexpression decreased the GPX3 protein level by promoting its ubiquitination, without affecting the GPX3 mRNA level. Thus, TRIM6 facilitates GPX3 ubiquitination, contributing to increased ROS levels and pyroptosis in HK2 cells. CONCLUSIONS: TRIM6 increases oxidative stress and promotes the pyroptosis of HK2 cells by regulating GPX3 ubiquitination. These findings could contribute to the development of novel drugs for the treatment of RF.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Piroptose , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Transdução de Sinais , Inflamação , Acetilcisteína/metabolismo , Acetilcisteína/farmacologia , Superóxido Dismutase/metabolismo , Células Epiteliais/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/farmacologia , Ubiquitinação , Malondialdeído/metabolismo , RNA Mensageiro/metabolismo
3.
Aging (Albany NY) ; 15(15): 7673-7688, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37552124

RESUMO

Diabetic kidney disease (DKD) poses a threat to people's health. The current treatments only provide partial relief of symptoms. Therefore, seeking a promising therapeutic medication for the prevention and control on DKD will benefit patients. Recently, a novel iron-dependent and non-apoptotic regulated mode of cell death, termed as ferroptosis, is expected to offer us a novel insight into the mechanism of DKD. We conducted experiments to investigate the role of ferroptosis in the development of DKD. Iron accumulation, weakened antioxidant capacity and ROS overproduction were observed in the renal tissues of STZ-induced diabetic rats. A persistent high glucose condition contributed to down regulated levels of Glutathione Peroxidase 4 (GPX4) and Solute Carrier Family 7 Member 11 (SLC7A11) which marked the occurrence of ferroptosis. Treatment of Emodin in DKD models could significantly attenuated these changes and reduced renal injury. Besides, NFE2-related factor 2 (Nrf2), an important antioxidant regulator, was inhibited in both in vivo and in vitro assay, which contributes to Reactive Oxygen Species (ROS) generation that further promoted the expression of ferroptosis related protein. These unwanted effects were offset by the intervention of Emodin. The specific Nrf2 knock out enhanced cell's sensitivity to ferroptosis by being exposed to high glucose culture, which was improved by treatment of Emodin via restoring activity of Nrf2. In conclusion, our research demonstrated that Emodin exerted renal protection against DKD via inhibiting ferroptosis and restoring Nrf2 mediated antioxidant capacity, which could be employed as a novel therapeutic medication against DKD.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Emodina , Ferroptose , Animais , Ratos , Nefropatias Diabéticas/tratamento farmacológico , Emodina/farmacologia , Emodina/uso terapêutico , Fator 2 Relacionado a NF-E2/genética , Antioxidantes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Espécies Reativas de Oxigênio , Glucose , Ferro
4.
J Psychiatr Res ; 158: 165-171, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586215

RESUMO

OBJECTIVE: Because of the similar clinical symptoms, it is difficult to distinguish unipolar disorder (UD) from bipolar disorder (BD) in the depressive episode using the available clinical features, especially for those who meet the diagnostic criteria of UD, however, experience the manic episode during the follow-up (tBD). METHODS: Magnetoencephalography recordings during a sad expression recognition task were obtained from 81 patients (27 BD, 24 tBD, 30 UD) and 26 healthy controls (HCs). Source analysis was applied to localize 64 regions of interest in the low gamma band (30-50 Hz). Regional functional connections (FCs) were constructed respectively within three time periods (early: 0-200 ms, middle: 200-400 ms, and post: 400-600 ms). The network-based statistic method was used to explore the abnormal connection patterns in tBD compared to UD and HC. BD was applied to explore whether such abnormality is still significant between every two groups of BD, tBD, UD, and HC. RESULTS: The VMPFC-PreCG.L connection was found to be a significantly different connection between tBD and UD in the early time period and between tBD and BD in the middle time period. Furthermore, the middle/early time period ratio of FC value of VMPFC-PreCG.L connection was negatively correlated with the bipolarity index in tBD. CONCLUSIONS: The VMPFC-PreCG.L connection in different time periods after the onset of sad facial stimuli may be a potential biomarker to distinguish the different states of BD. The FC ratio of VMPFC-PreCG.L connection may predict whether patients with depressive episodes subsequently develop mania.


Assuntos
Transtorno Bipolar , Transtorno Depressivo , Humanos , Mania , Encéfalo , Imageamento por Ressonância Magnética/métodos
5.
Front Pharmacol ; 13: 1015966, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304171

RESUMO

Dementia is a syndrome that impairs learning and memory. To date, there is no effective therapy for dementia. Current prescription drugs, such as cholinesterase inhibitors, fail to improve the condition of dementia and are often accompanied by severe adverse effects. In recent years, the number of studies into the use of traditional Chinese medicine (TCM) for dementia treatment has increased, revealing a formula that could significantly improve memory and cognitive dysfunctions in animal models. TCM showed fewer adverse effects, lower costs, and improved suitability for long-term use compared with currently prescribed drugs. Due to the complexity of ingredients and variations in bioactivity of herbal medicines, the multi-target nature of the traditional Chinese formula affected the outcome of dementia therapy. Innovations in TCM will create a platform for the development of new drugs for the prevention and treatment of dementia, further strengthening and enhancing the current influence of TCM.

6.
Comput Math Methods Med ; 2022: 5063636, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341010

RESUMO

Among all the complications of diabetes, diabetic nephropathy is a significant factor causing the end-stage renal disease associated with high death rates. Current treatment fails to produce an ideal outcome. Thus, searching for a new preventive drug is urgently needed. Liuwei Dihuang pill (LDP), a popular ancient Chinese medicine (TCM) prescription, has been applied to treat DN-like syndromes according to TCM theory. Here, we had established an animal model with DN and LDP therapy was put into use to assess its therapeutic effect in vivo. Our data showed that oxidative stress and TGF-ß/Smad2/3 pathway-induced renal fibrosis could be observed in the DN animal model. However, the treatment of LDP impeded the generation of ROS and attenuated renal fibrosis-related proteins in damaged kidneys through interference in the TGF-ß/Smad3 pathway. Our results indicated that LDP attenuated oxidative stress, accompanied by preventing the production of renal fibrosis through inhibiting the TGF-ß/Smad2/3 pathway.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Fibrose , Rim , Camundongos , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta/uso terapêutico
7.
Turk Neurosurg ; 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37309629

RESUMO

AIM: About 6-17% of pituitary neuroendocrine tumors (PitNETs) are invasive. Cavernous sinus invasion complicates neurosurgery, making total tumor resection impossible and leading to high recurrence postoperatively. This study detected Endocan, FGF2, and PDGF to examine the associations of these angiogenic factors with the invasiveness of PitNETs and to identify novel therapeutic targets in PitNETs. MATERIAL AND METHODS: Endocan mRNA amounts (qRT-PCR) in 29 human PitNET specimens obtained after surgery were assessed alongside clinical parameters (PitNET lineage, sex, age, and imaging data). In addition, qRT-PCR was used to determine the gene expression of other angiogenic markers (FGF-2 and PDGF). RESULTS: Endocan was positively associated with PitNET invasiveness. Endocan expressing specimens had elevated FGF2 amounts, and FGF2 and PDGF were negatively correlated. CONCLUSION: A complex but precise balance was found among Endocan, FGF2, and PDGF in pituitary tumorigenesis. High Endocan and FGF2 and low PDGF expression levels in invasive PitNETs show Endocan and FGF2 could be novel treatment targets in invasive PitNET.

8.
Front Immunol ; 13: 1080456, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36601125

RESUMO

Diabetic kidney disease (DKD), an emerging global health issue, is one of the most severe microvascular complications derived from diabetes and a primary pathology contributing to end-stage renal disease. The currently available treatment provides only symptomatic relief and has failed to delay the progression of DKD into chronic kidney disease. Recently, multiple studies have proposed a strong link between intestinal dysbiosis and the occurrence of DKD. The gut microbiota-derived short-chain fatty acids (SCFAs) capable of regulating inflammation, oxidative stress, fibrosis, and energy metabolism have been considered versatile players in the prevention and treatment of DKD. However, the underlying molecular mechanism of the intervention of the gut microbiota-kidney axis in the development of DKD still remains to be explored. This review provides insight into the contributory role of gut microbiota-derived SCFAs in DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Microbioma Gastrointestinal , Insuficiência Renal Crônica , Humanos , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/prevenção & controle , Nefropatias Diabéticas/patologia , Microbioma Gastrointestinal/fisiologia , Rim/patologia , Ácidos Graxos Voláteis/metabolismo , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/prevenção & controle
9.
Front Pharmacol ; 12: 825330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35242028

RESUMO

Dementias is a kind of neurodegenerative disease, which occurs among the aging population. Current therapeutic outcome for dementia is limited. The medical use of herbal plant has a rich history in traditional Chinese medicine practice for thousands of years. Herbal medicine (HM) may provide a positive effect for prevention and treatment in dementia. As an alternative treatment to dementia, there has been a growing interest in HM extracts in scientific community as a result of its promising study results, mainly in animal experiment. At the molecular level, HM extracts trigger autophagy and reduce generation of reactive oxygen species (ROS) while inhibiting inflammation and reduce neurotoxicity. Experiments both in vivo and in vitro have identified certain potential of HM extracts and natural products as an important regulator factor in mediating autophagy, which might contribute to the improvement of dementia. This brief review not only summarizes the mechanism of autophagy in dementia but also offers a general understanding of the therapeutic mechanism of HM extracts in treating dementia and evaluates the potential clinical practice of HM in general.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33121427

RESUMO

Diabetic nephropathy (DN) is referred to as the microvascular complication of the kidneys induced by insufficient production of insulin or an ineffective cellular response to insulin, and is the main cause of end-stage renal disease. Currently, available therapies provide only symptomatic relief and fail to improve the outcome of diabetic nephropathy. Studies on diabetic animals had shown overexpression of SIRT1 in both podocytes and renal tubular cells attenuated proteinuria and kidney injury in the animal model of DN. Sirt1 exerts renoprotective effects in DKD in part through the deacetylation of transcription factors involved in the disease pathogenesis, such as NF-кB, Smad3, FOXO and p53. The purpose of this review is to highlight the protective mechanism of SIRT1 involved in the pathogenesis of diabetic nephropathy.


Assuntos
Diabetes Mellitus/metabolismo , Diabetes Mellitus/prevenção & controle , Nefropatias Diabéticas/metabolismo , Sirtuína 1/metabolismo , Animais , Diabetes Mellitus/patologia , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/prevenção & controle , Humanos , Rim/metabolismo , Rim/patologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Podócitos/metabolismo , Podócitos/patologia
11.
Brain ; 142(8): 2265-2275, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31211368

RESUMO

The natural history of intradural spinal cord arteriovenous shunts is unknown. We performed an observational study in a consecutive patient cohort with symptomatic intradural spinal cord arteriovenous shunts who were admitted to three institutes to investigate the clinical course of this complex disease, which would provide valuable evidence to inform clinical decision-making. The clinical course of patients with symptomatic intradural spinal cord arteriovenous shunts from initial presentation to occurrence of clinical deterioration, initiation of treatment, or last follow-up was analysed. Patients with at least 1 month of observation were included in this study. Clinical onset and deterioration patterns were divided into acute and gradual. Annual and cumulative rates of clinical deterioration as well as their risk factors were analysed using Kaplan-Meier life table analysis and Cox proportional hazards model. To assess risks and benefits of treatment, post-treatment clinical courses were further assessed. Four hundred and sixty-six patients with a mean observational period of 36.9 ± 58.8 months were included; 56.7% of patients presented with acute onset, of whom 77.3% experienced spontaneous recovery. Age of onset older than 28 years, initial modified Aminoff and Logue scale of >3, mid-thoracic lesions and non-ventral lesions were independent predictors of failure for spontaneous recovery. The annual risk of general, acute and gradual clinical deterioration after onset was 30.7%, 9.9% and 17.7%, respectively. Risk of deterioration was highest in the early period after initial onset. Acute onset was the only independent risk factor [hazard ratio 1.957 (95% confidence interval, CI 1.324-2.894); P = 0.0008] of acute deterioration and gradual onset was the strongest predictor [hazard ratio 2.350 (95% CI 1.711-3.229); P < 0.0001] of the gradual deterioration among all the stratifying factors. After invasive treatment, complete obliteration was achieved in 37.9% of patients (138 of 364) and improved or stable clinical status was noted in 80.8% of patients. Forty-two patients (11.5%) experienced permanent complications. Overall post-treatment deterioration rate was 8.4%/year, and 5.3%/year if permanent complications were excluded. The natural history of symptomatic spinal cord arteriovenous shunts is poor, especially in the early period after onset, and early intervention is thus recommended. Initial onset pattern significantly affects the natural history of the lesion, which prompts a differentiated treatment strategy.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Medula Espinal/anormalidades , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Masculino , Recuperação de Função Fisiológica , Adulto Jovem
12.
J Pharmacol Sci ; 139(4): 367-372, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30929858

RESUMO

Renal fibrosis is a common pathological change in all stages of kidney disease. Kangxianling decoction was widely used in patients with chronic kidney disease, which could improve symptoms such as poor appetite, edema, and fatigue. However, its effect on renal fibrosis remains to be studied. In this study, we investigated its effects on renal fibrosis in a rat model of 5/6 Nephrectomy (5/6 N) in vivo and in angiotensin II (Ang II)-treated rat glomerular mesangial cells (HBZY-1) in vitro. Our data showed that 5/6 N induced renal fibrosis and combined with the activation of JNK signaling, the upregulation of transforming growth factor-ß (TGF-ß), collagen I (Col-I) and fibronectin (FN). The administration of kangxianling decoction inhibited the activation of JNK signaling and attenuated the deposition of extracellular matrix (ECM) proteins in damaged kidneys. In HBZY-1 cells, Ang II increased the protein expression of Col-I and FN. It also activates JNK signaling and TGF-ß in a time-dependent manner. Treatment of the HBZY-1 cells with kangxianling decoction blocked Ang II-induced JNK activation and ECM overproduction. Our results indicated that Kangxianling Decoction could reduce renal fibrosis, accompanied by inhibiting the production of ECM proteins and JNK, along with downregulation of TGF-ß, Ang II.


Assuntos
Angiotensina II/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Mesângio Glomerular/metabolismo , Nefropatias/patologia , Nefropatias/prevenção & controle , Rim/patologia , Células Mesangiais/metabolismo , Nefrectomia , Animais , Células Cultivadas , Colágeno/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Fibronectinas/metabolismo , Fibrose , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
World Neurosurg ; 98: 546-554, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27890764

RESUMO

BACKGROUND: Spontaneous spinal epidural hematoma (SSEH) is a rare neurologic emergency of the spinal cord. Its cause and treatment strategy remain controversial. This study aimed to evaluate a significant cause of SSEH and to discuss the treatment strategy according to the clinical outcomes of patients in 2 institutions. METHODS: Fifty-five cases of SSEH treated at our institutions between February 2002 and February 2016 were retrospectively analyzed. RESULTS: The mean age of the first SSEH onset was 31.8 years. The follow-up rate was 72.7%, with 28 patients (70%) showing satisfactory clinical outcomes. Forty patients received preoperative spinal digital subtraction angiography. Spinal epidural (extradural) arteriovenous fistula was detected in 6 patients (15%), 5 of whom showed 1 type of special slow-flow shunt. Nineteen patients (34.5%) suffered from multiple episodes until they underwent invasive treatments or last follow-up. Rebleeding was confirmed in 8 patients. None of the patients had a subsequent episode or rebleeding after invasive treatment. The risk factors for poor clinical outcome included advanced age at initial onset (P = 0.020), a short progression interval (P = 0.030), no symptom relief after admission (P = 0.011), hypesthesia (P = 0.017), complete spinal cord injury (P = 0.001), and hematoma below the T4 level (P = 0.014). CONCLUSIONS: Spinal epidural (extradural) arteriovenous fistula is a significant cause of SSEH. Standard spinal digital subtraction angiography is necessary for patients with SSEH. Conservative treatment could not prevent occurrence of multiple episodes or rebleeding in patients. Microsurgery should be recommended as the preferred treatment strategy for SSEH. Endovascular embolization is also recommended if applicable.


Assuntos
Hematoma Epidural Espinal/etiologia , Adolescente , Adulto , Idade de Início , Idoso , Criança , Pré-Escolar , Constipação Intestinal/etiologia , Incontinência Fecal/etiologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Hematoma Epidural Espinal/cirurgia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Incontinência Urinária/etiologia , Adulto Jovem
14.
Chem Commun (Camb) ; 52(75): 11300-11303, 2016 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-27709219

RESUMO

The enantioselective total synthesis of the 3,4-fused indole alkaloid ht-13-A has been achieved. The synthesis features a zinc-mediated propargylation, a rhodium-catalyzed intramolecular C-H activation reaction, and a methylamine-mediated cyclization. This concise and efficient synthetic approach can be applied for the gram-scale synthesis of ht-13-A.

15.
Chem Commun (Camb) ; 50(55): 7367-70, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24871379

RESUMO

The rhodium(III)-catalyzed intramolecular annulation of alkyne-tethered acetanilides for the synthesis of fused tricyclic indole scaffolds via C-H activation has been developed, which has the potential for the synthesis of many indole alkaloids. This reaction proceeds under mild reaction conditions and with tolerance to a variety of functional groups.


Assuntos
Indóis/química , Ródio/química
16.
J Org Chem ; 78(11): 5810-5, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23701029

RESUMO

The concise synthesis of the novel telomerase inhibitors dictyodendrins B and E was completed in only 9 and 11 steps (longest linear sequence). The highly convergent strategy employed a palladium-catalyzed Larock indole synthesis and a palladium-mediated one-pot consecutive Buchwald-Hartwig amination/C-H activation reaction as key steps. The present synthesis exhibits respectable levels of atom-, redox-, and step-economy.


Assuntos
Carbazóis/síntese química , Pirróis/síntese química , Carbazóis/química , Estrutura Molecular , Pirróis/química , Estereoisomerismo , Telomerase/antagonistas & inibidores
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