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1.
J Org Chem ; 89(7): 4474-4483, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38506434

RESUMO

A highly enantioselective Mannich reaction of α-fluoroindanones with isatin-derived N-Boc-ketimines catalyzed by a quinine-derived phase-transfer catalyst was developed. A variety of 3-substituted 3-amino-2-oxindoles bearing fluorine-containing, vicinal, tetrasubstituted stereocenters were constructed using this protocol in high yields (83-95%), with moderate to excellent enantioselectivities (66-91%) and high diastereoselectivities (up to >99:1).

2.
J Org Chem ; 87(5): 2532-2542, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35084194

RESUMO

A highly enantioselective aza-Friedel-Crafts reaction of 1H-indoles with isatin-derived N-Cbz-ketimines catalyzed by quinine-derived phase-transfer catalysts was developed. A series of chiral 3-aminobisindole compounds containing a tetrasubstituted stereocenter were constructed by this protocol in high yields (82-91%) and moderate to excellent enantioselectivities (46-94% ee).


Assuntos
Isatina , Catálise , Indóis , Estrutura Molecular , Estereoisomerismo
3.
J Org Chem ; 85(6): 4047-4057, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32130006

RESUMO

A series of bifunctional asymmetric phase-transfer catalysts containing novel fluorine-containing urea groups derived from cinchona alkaloids have been synthesized and successfully applied in the asymmetric intramolecular Mannich reaction. The 4-azaindoline products bearing multiple substrates were obtained in excellent yield (90-99%), with high enantioselectivity (up to 95%) and diastereoselectivity (up to >99:1).

4.
Org Biomol Chem ; 18(37): 7431-7436, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32936203

RESUMO

An efficient enantioselective addition of thiols to acyclic trifluoromethyl ketimines has been established by using a bifunctional squaramide catalyst, which was derived from quinine, and the reaction was completed in 5 to 10 min. The construction of chiral tetrasubstituted carbon centers bearing trifluoromethylated N,S-ketals has been achieved in high yields (up to 96% yield) with excellent enantioselectivities (up to 99% ee).

5.
Biol Chem ; 400(9): 1217-1228, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-30738012

RESUMO

Parkinson's disease (PD) is a common neurological disorder characterized by dopaminergic (DA) neuron degeneration and death in the midbrain, and the long noncoding RNA HOTAIR has been shown to affect disease progression in PD. In this study, we aimed to further illustrate the molecular mechanism of HOTAIR in PD. Bioinformatics analysis was utilized to determine the potential downstream targets of HOTAIR in PD. Luciferase assay and the RNA Binding Protein Immunoprecipitation (RIP) assay were used to validate the existence of binding sites between competing endogenous RNAs (ceRNAs). Real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting indicated that HOTAIR and RAB3IP increased while miR-126-5p decreased in PD cells and PD mice. Additionally, the CCK-8 assay and flow cytometric analysis indicated that the knockdown of HOTAIR and RAB3IP and the overexpression of miR-126-5p significantly increased cell proliferation and reduced apoptosis in PD cells. Furthermore, the results of in vivo experiments suggested that knockdown of HOTAIR expression increased the number of TH-positive cells and the number of α-synuclein-positive cells decreased while reducing the apoptosis rate among DA neurons. Our study confirmed that HOTAIR promotes PD progression by regulating miR-126-5p and RAB3IP in a ceRNA-dependent manner and further clarified how HOTAIR works in PD.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , MicroRNAs/genética , Doença de Parkinson/patologia , RNA Longo não Codificante/genética , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Humanos , Regulação para Cima
6.
J Org Chem ; 83(3): 1486-1492, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29271656

RESUMO

An efficient enantioselective aza-Henry reaction of aryl α-ketoester-derived ketimines has been realized by using bifunctional thiourea-ammonium salt phase-transfer catalysts, which were derived from quinine. A variety of aryl α-ketoester-derived N-Ts ketimines were investigated, and the corresponding products were obtained in high to excellent yields (up to 99%) with good to high enantioselectivities (up to >99% ee).


Assuntos
Compostos de Amônio/química , Alcaloides de Cinchona/química , Iminas/química , Nitrilas/química , Tioureia/química , Catálise , Estrutura Molecular , Sais/química , Estereoisomerismo
7.
Org Biomol Chem ; 16(46): 8927-8932, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30431642

RESUMO

A highly diastereo- and enantioselective Mannich reaction of isatin-derived ketimines with oxo-indanecarboxylates catalyzed by chiral thiourea derived from hydroquinidine has been developed. A series of 3-substituted 3-amino-oxindoles containing assembled bicyclic rings linked by a C-C bond were constructed by this protocol in excellent yields (92-99%) with high enantioselectivities (85-99% ee) and diastereoselectivities (up to >99 : 1 dr).

8.
J Org Chem ; 82(9): 4668-4676, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28418251

RESUMO

A high-yield, highly diastereo- and enantioselective nitro-Mannich reaction of α-aryl nitromethanes with amidosulfones catalyzed by a novel chiral phase-transfer catalyst, bearing multiple H-bonding donors, derived from quinine was developed. A variety of α-aryl nitromethanes and amidosulfones were investigated; and the corresponding products were obtained in excellent yields with excellent diastereo- and enantioselectivities (up to 99% yield, > 99:1 dr and >99% ee). As a demonstration of synthetic utility, the resulting ß-nitroamines could be converted to corresponding meso-symmetric and optically pure unsymmetric anti-1,2-diarylethylenediamines.

9.
Org Biomol Chem ; 15(43): 9234-9242, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29085949

RESUMO

New quaternary ammonium types of bifunctional asymmetric phase-transfer catalysts bearing multiple hydrogen-bonding donors derived from α-amino acids were readily prepared and found to be highly efficient in the asymmetric nitro-Mannich reactions of amidosulfones. Very broad substrate generality was observed, and the products were achieved in high enantio-/diastereoselectivities (90->99.9% ee, 90 : 10 to 92 : 8 dr). Compared with previous reports, the enantioselectivity of aliphatic amidosulfones has been improved to a high level (91-93% ee).


Assuntos
Aminoácidos/química , Nitrocompostos/química , Catálise , Ligação de Hidrogênio , Estereoisomerismo
10.
J Org Chem ; 81(23): 11950-11955, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27802591

RESUMO

We have developed a new base-promoted intermolecular cascade cyclization reaction of substituted 3-aryl(heteroaryl)-3-chloroacrylaldehydes and tetrahydroisoquinolines in one pot. The reaction provides a facile and practical synthesis of pyrrolo[2,1-a]isoquinolines. A number of pyrrolo[2,1-a]isoquinolines were synthesized in moderate to high yields (up to 97%).

11.
Front Behav Neurosci ; 18: 1420028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39184934

RESUMO

The nucleus accumbens (NAc), a central component of the brain's reward circuitry, has been implicated in a wide range of behaviors and emotional states. Emerging evidence, primarily drawing from recent rodent studies, suggests that the function of the NAc in reward and aversion processing is multifaceted. Prolonged stress or drug use induces maladaptive neuronal function in the NAc circuitry, which results in pathological conditions. This review aims to provide comprehensive and up-to-date insights on the role of the NAc in motivated behavior regulation and highlights areas that demand further in-depth analysis. It synthesizes the latest findings on how distinct NAc neuronal populations and pathways contribute to the processing of opposite valences. The review examines how a range of neuromodulators, especially monoamines, influence the NAc's control over various motivational states. Furthermore, it delves into the complex underlying mechanisms of psychiatric disorders such as addiction and depression and evaluates prospective interventions to restore NAc functionality.

12.
EBioMedicine ; 108: 105342, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39321499

RESUMO

BACKGROUND: Which cell populations that determine the fate of bacteria in infectious granulomas remain unclear. Leprosy, a granulomatous disease with a strong genetic predisposition, caused by Mycobacterium leprae infection, exhibits distinct sub-types with varying bacterial load and is considered an outstanding disease model for studying host-pathogen interactions. METHODS: We performed single-cell RNA and immune repertoire sequencing on 11 healthy controls and 20 patients with leprosy, and integrated single-cell data with genome-wide genetic data on leprosy. Multiplex immunohistochemistry, and in vitro and in vivo infection experiments were conducted to confirm the multimodal omics findings. FINDINGS: Lepromatous leprosy (L-LEP) granulomas with high bacterial burden were characterised by exhausted CD8+ T cells, and high RGS1 expression in CD8+ T cells was associated with L-LEP. By contrast, tuberculoid leprosy (T-LEP) granulomas with low bacterial burden displayed enrichment in resident memory IFNG+ CD8+ T cells (CD8+ Trm) with high GNLY expression. This enrichment was potentially attributable to the communication between IL1B macrophages and CD8+ Trm via CXCL10-CXCR3 signalling. Additionally, IL1B macrophages in L-LEP exhibited anti-inflammatory phenotype, with high APOE expression contributing to high bacterial burden. Conversely, IL1B macrophages in T-LEP were distinguished by interferon-γ induced GBP family genes. INTERPRETATION: The state of IL1B macrophages and functional CD8+ T cells, as well as the relationship between them, is crucial for controlling bacterial persistence within granulomas. These insights may indicate potential targets for host-directed immunotherapy in granulomatous diseases caused by mycobacteria and other intracellular bacteria. FUNDING: The Key research and development program of Shandong Province (2021LCZX07), Natural Science Foundation of Shandong Province (ZR2023MH046), Youth Science Foundation Cultivation Funding Plan of Shandong First Medical University (Shandong Academy of Medical Sciences) (202201-123), National Natural Science Foundation of China (82471800, 82230107, 82273545, 82304039), the China Postdoctoral Science Foundation (2023M742162), Shandong Province Taishan Scholar Project (tspd20230608), Joint Innovation Team for Clinical & Basic Research (202410), Central guidance for local scientific and technological development projects of Shandong Province (YDZX2023058).

13.
Nat Commun ; 15(1): 6259, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048559

RESUMO

Pityriasis rubra pilaris (PRP) is an inflammatory papulosquamous dermatosis, characterized by hyperkeratotic follicular papules and erythematous desquamative plaques. The precise pathogenic mechanism underlying PRP remains incompletely understood. Herein, we conduct a case-control study involving a cohort of 102 patients with sporadic PRP and 800 healthy controls of Han Chinese population and identify significant associations (P = 1.73 × 10-6) between PRP and heterozygous mutations in the Keratin 32 gene (KRT32). KRT32 is found to be predominantly localized in basal keratinocytes and exhibits an inhibitory effect on skin inflammation by antagonizing the NF-κB pathway. Mechanistically, KRT32 binds to NEMO, promoting excessive K48-linked polyubiquitination and NEMO degradation, which hinders IKK complex formation. Conversely, loss-of-function mutations in KRT32 among PRP patients result in NF-κB hyperactivation. Importantly, Krt32 knockout mice exhibit a PRP-like dermatitis phenotype, suggesting compromised anti-inflammatory function of keratinocytes in response to external pro-inflammatory stimuli. This study proposes a role for KRT32 in regulating inflammatory immune responses, with damaging variants in KRT32 being an important driver in PRP development. These findings offer insights into the regulation of skin immune homeostasis by keratin and open up the possibility of using KRT32 as a therapeutic target for PRP.


Assuntos
Queratinócitos , Pitiríase Rubra Pilar , Pele , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem , Estudos de Casos e Controles , Homeostase , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Queratinócitos/imunologia , Queratinócitos/metabolismo , Queratinas/metabolismo , Queratinas/genética , Mutação com Perda de Função , Camundongos Knockout , NF-kappa B/metabolismo , Pitiríase Rubra Pilar/genética , Pitiríase Rubra Pilar/imunologia , Pitiríase Rubra Pilar/patologia , Pitiríase Rubra Pilar/metabolismo , Transdução de Sinais , Pele/patologia , Pele/imunologia , Pele/metabolismo , Ubiquitinação
14.
Bioinformatics ; 28(8): 1172-3, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22368247

RESUMO

MOTIVATION: Computational characterization of ligand-binding sites in proteins provides preliminary information for functional annotation, protein design and ligand optimization. SiteComp implements binding site analysis for comparison of binding sites, evaluation of residue contribution to binding sites and identification of sub-sites with distinct molecular interaction properties. AVAILABILITY AND IMPLEMENTATION: The SiteComp server and tutorials are freely available at http://sitecomp.sanchezlab.org.


Assuntos
Proteínas/química , Proteínas/metabolismo , Software , Sítios de Ligação , Computadores , Ligantes , Modelos Moleculares , Prostaglandina-Endoperóxido Sintases/química , Prostaglandina-Endoperóxido Sintases/metabolismo
15.
Nutrients ; 15(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068762

RESUMO

Hyperlipidemia (HLP) is a metabolic syndrome induced by obesity, which has been widely recognized as a significant threat to human health. Pleurotus abieticola, an edible lignin-degrading fungus, remains relatively understudied in terms of its bioactivity and medicinal properties. In this study, the lipid-lowering effect of Pleurotus abieticola polysaccharide (PAPS1) was systematically explored in high-fat diet (HFD)-induced HLP mice. The findings demonstrated that the administration of PAPS1 significantly inhibited bodyweight gain, ameliorated blood glucose and lipid levels, reduced fat accumulation, and mitigated hepatic injury in HLP mice. In addition, PAPS1 demonstrated the capability to increase the levels of three distinct fecal metabolites while simultaneously reducing the levels of eight other fecal metabolites in HLP mice. According to biological detection, PAPS1 reduced the hepatic level of reactive oxygen species (ROS) and pro-inflammatory factors, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, -6, -17A, -22, and -23, and increased the expression of anti-inflammatory factor IL-10. Combined with proteomics, Western blot and immunohistochemistry analysis showed that PAPS1 exerted suppressive effects on inflammation and oxidative damage by inhibiting the nuclear factor-κB (NF-κB)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in HLP mice. These findings offer evidence supporting the effectiveness of PAPS1 as a therapeutic agent in reducing lipid levels through its targeting of chronic inflammation.


Assuntos
Hiperlipidemias , NF-kappa B , Humanos , Camundongos , Animais , NF-kappa B/metabolismo , Hiperlipidemias/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Inflamação/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Lipídeos
17.
ACS Omega ; 6(8): 5812-5824, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33681620

RESUMO

A series of chiral thiourea bearing multiple H-bond donors derived from hydroquinine has been reported. The aza-Henry reaction of isatin-derived ketimines and long-chain nitroalkanes catalyzed by these chiral thioureas can achieve high enantioselectivity (78-99% ee) and excellent diastereoselectivity (up to 99:1). This work is the first report on long-chain nitroalkanes as substrates with excellent diastereoselectivity in metal-free catalytic systems.

18.
Langmuir ; 26(9): 6676-80, 2010 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-20070084

RESUMO

The synthesis and characterization of carbon-coated ferromagnetic nanoparticles that organize into 1-D assemblies of micrometer-sized ferromagnetic chains is described. A controlled aromatization and carbonization of glucose under hydrothermal reaction conditions enabled the preparation of carbonaceous surfactants that were used as shells for the coating of ferromagnetic Fe(3)O(4) nanospheres with a uniform size distribution. Under controlled experimental conditions, it was, for the first time, demonstrated that glucose could be employed as the carbon source in the preparation of continuous 1-D carbon nanoparticle chains with magnetic nanosphere inclusions. The functional groups on the carbon surface will facilitate the linkage of functional groups or catalytic species to the surface in future application. The salient feature of the reported method was the assembly of magnetic nanospheres under hydrothermal reaction conditions in the absence of external fields.

19.
Org Biomol Chem ; 8(13): 3078-82, 2010 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-20480101

RESUMO

A facile and convenient synthesis of substituted pyridines has been developed via a one-pot multicomponent reaction of easily available 1,3-dicarbonyl compounds, aromatic aldehydes, malononitrile and alcohol in the presence of NaOH under mild conditions. A series of functionalized pyridines were thus obtained by this multicomponent reaction, in which four new bonds were formed in a highly chemo- and regioselective manner, and alcohol played dual roles as both reactant and reaction medium. Particularly valuable features of this protocol including mild conditions, simple execution, broad substrate scope, and good yields of products make it an efficient and promising synthetic strategy to build pyridine skeleton.


Assuntos
Piridinas/química , Piridinas/síntese química , Indicadores e Reagentes/química
20.
Neuroreport ; 31(9): 637-643, 2020 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-32427711

RESUMO

Increasing evidence verified that oxidative stress and neuroinflammatory response exacerbates motor deficits and increases neuronal loss in several rodent models of Parkinson's disease. In the present study, we explore the neuroprotective effects of monascin in a rotenone-induced Parkinson's disease model as well as the underlying mechanisms. Our results showed that monascin remarkedly attenuated behavioral impairments and the depletion of dopaminergic neurons induced by rotenone in the rats. Besides, monascin decreased the levels of pro-inflammatory factors such as interleukin-1ß, interleukin-6, tumor necrosis factor-α and oxidative stress marker malondialdehyde while promoted the expression of superoxide dismutase, glutathione peroxidase and other antioxidant factors. Further detection of the expression of related proteins showed that monascin significantly promoted the expression of proliferator-activated receptor-gamma, F-E2-related factor 2 and heme oxygenase-1, but inhibited the expression of NF-κB. What's more, levels of growth factors that are essential for neuronal and synaptic function were increased under the effects of monascin. All in all, our results revealed that monascin exerted neuroprotective effects in rotenone model of Parkinson's disease via antioxidation and anti-neuroinflammation.


Assuntos
Encefalite/metabolismo , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Animais , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Masculino , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Ratos Sprague-Dawley , Rotenona/administração & dosagem
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