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1.
J Org Chem ; 89(7): 4474-4483, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38506434

RESUMEN

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.
Nutrients ; 15(23)2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38068762

RESUMEN

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.


Asunto(s)
Hiperlipidemias , FN-kappa B , Humanos , Ratones , Animales , FN-kappa B/metabolismo , Hiperlipidemias/tratamiento farmacológico , Factor de Transcripción STAT3/metabolismo , Inflamación/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Lípidos
3.
J Org Chem ; 87(5): 2532-2542, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35084194

RESUMEN

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).


Asunto(s)
Isatina , Catálisis , Indoles , Estructura Molecular , Estereoisomerismo
4.
ACS Omega ; 6(8): 5812-5824, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33681620

RESUMEN

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.

5.
Org Biomol Chem ; 18(37): 7431-7436, 2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32936203

RESUMEN

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).

6.
Neuroreport ; 31(9): 637-643, 2020 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-32427711

RESUMEN

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.


Asunto(s)
Encefalitis/metabolismo , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Enfermedad de Parkinson/metabolismo , Animales , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/efectos de los fármacos , Masculino , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/metabolismo , Ratas Sprague-Dawley , Rotenona/administración & dosificación
7.
J Org Chem ; 85(6): 4047-4057, 2020 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-32130006

RESUMEN

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).

8.
Front Chem ; 7: 692, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31737594

RESUMEN

Two new (1, 2) and one known (3) meroterpenoids were isolated from the deep-sea-derived fungus Penicillium allii-sativi. The relative structures of new compounds were determined on the basis of an extensive analysis of the NMR and MS data, and the absolute configurations were established by ECD calculations. Andrastone A (1) is a rare andrastin bearing an unusual cyclopentan-1,3-dione. It shows a selectively antiproliferative effect against HepG2 tumor cells with an IC50 value of 7.8 µM. Mechanism study showed that apoptosis via Caspase and RXRα pathways are responsible for the inhibitory effect.

9.
Free Radic Res ; 53(11-12): 1073-1083, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31631710

RESUMEN

Of all the aerobic respiration by-products, cytotoxic superoxide derived from mitochondrial-leaked electrons, is the only one known to be disposed of intracellularly. Is this fate the only destiny for mitochondrial-leaked electrons? When Cynomolgus monkeys were injected intravenously with reactive oxygen species (ROS) indicators, the connective tissues of dura mater, facial fascia, pericardium, linea alba, dorsa fascia and other body parts, emitted specific and intense fluorescent signals. Moreover, the fluorescent signals along the linea alba of SD rats, did not result from the local presence of ROS but from the interaction of ROS indicators with electrons flowing through this tissue. Furthermore, the electrons travelling along the linea alba of mice were revealed to originate from mitochondria. These data suggest that mitochondrial-leaked electrons may be transported extracellularly to a hitherto undescribed system of connective tissues, which is pervasively networked, electrically conductive and metabolically related.


Asunto(s)
Especies Reactivas de Oxígeno/análisis , Pared Abdominal , Animales , Fluorescencia , Colorantes Fluorescentes/administración & dosificación , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacocinética , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
10.
Org Lett ; 21(14): 5719-5724, 2019 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-31265315

RESUMEN

N,N'-Acetals are sensitive compounds, and the challenging asymmetric synthesis of acyclic N,N'-acetals by the general addition of amines to ketimines has never been reported so far. In this study, highly enantioselective addition of aryl amines to isatin-derived ketimines catalyzed by chiral urea derived from quinine was developed. A series of new acyclic N,N'-acetals were constructed by this protocol in high to excellent yields (78-99%) and high to excellent enantioselectivities (76-96% ee).

11.
Biol Chem ; 400(9): 1217-1228, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-30738012

RESUMEN

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.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/genética , MicroARNs/genética , Enfermedad de Parkinson/patología , ARN Largo no Codificante/genética , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Humanos , Regulación hacia Arriba
12.
Org Biomol Chem ; 16(46): 8927-8932, 2018 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-30431642

RESUMEN

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).

13.
J Org Chem ; 83(3): 1486-1492, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29271656

RESUMEN

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).


Asunto(s)
Compuestos de Amonio/química , Alcaloides de Cinchona/química , Iminas/química , Nitrilos/química , Tiourea/química , Catálisis , Estructura Molecular , Sales (Química)/química , Estereoisomerismo
14.
RSC Adv ; 8(50): 28376-28385, 2018 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-35542465

RESUMEN

Prolinamides with double-H potential were prepared and employed as organocatalysts in asymmetric aldol reactions. The catalyst with adamantane showed improved catalytic activity, which was further enhanced by using brine as the solvent. A series of aldol reactions in brine at 0 °C provided good yields (up to 98%) with high diastereoselectivities (>99 : 1) and enantioselectivities (>99%). The prepared catalyst was adsorbed by a nanofibrous film of poly(AN-MA-ß-CD) via host-guest interaction in the reaction system. The catalyst was separated from the film by applying ultrasound, with a total recovery of 96.2%. The catalyst was reused up to five times without a significant change in diastereoselectivity and enantioselectivity.

15.
Org Biomol Chem ; 15(43): 9234-9242, 2017 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-29085949

RESUMEN

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).


Asunto(s)
Aminoácidos/química , Nitrocompuestos/química , Catálisis , Enlace de Hidrógeno , Estereoisomerismo
17.
J Org Chem ; 82(9): 4668-4676, 2017 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-28418251

RESUMEN

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.

18.
J Org Chem ; 81(23): 11950-11955, 2016 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-27802591

RESUMEN

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%).

19.
ACS Appl Mater Interfaces ; 8(13): 8393-400, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-26974545

RESUMEN

For the first time, homogeneous and well-ordered functional nanoarrays were grown densely on the complex structured three-dimensional (3D) printing frameworks through a general plasma enhanced atomic layer deposition (PEALD) assisted hydrothermal surface engineering process. The entire process was free from toxic additives or harmful residues and, therefore, can meet the critical requirements of high-purity products. As a practical example, 3D customized earplugs were precisely manufactured according to the model of ear canals at the 0.1 mm level. Meanwhile, well-ordered ZnO nanoarrays, formed on the surfaces of these 3D printed earplugs, could effectively prevent the growth of five main pathogens derived from the patients with otitis media and exhibited excellent wear resistance as well. On the basis of both animal experiments and volunteers' investigations, the 3D customized earplugs showed sound insulation capabilities superior to those of traditional earplugs. Further animal experiments demonstrated the potential of as-modified implant scaffolds in practical clinical applications. This work, exemplified with earplugs and implant scaffolds, oriented the development direction of 3D printing in biomedical devices, which precisely integrated customized architecture and tailored surface performance.


Asunto(s)
Dispositivos de Protección de los Oídos , Otitis Media/terapia , Impresión Tridimensional , Óxido de Zinc/química , Animales , Conducto Auditivo Externo/fisiopatología , Humanos , Nanoestructuras/química , Nanoestructuras/uso terapéutico , Otitis Media/microbiología , Gases em Plasma , Andamios del Tejido , Óxido de Zinc/uso terapéutico
20.
Org Lett ; 16(24): 6432-5, 2014 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-25489796

RESUMEN

Bifunctional asymmetric phase-transfer catalysts bearing multiple hydrogen-bonding donors have rarely been explored. The first quaternary ammonium type of these catalysts derived from cinchona alkaloids were readily prepared and found to be highly efficient catalysts for asymmetric nitro-Mannich reactions of amidosulfones. Compared with previous reports, very broad substrate generality was observed, and both enantiomers of the products were achieved in high enantio- and diastereoselectivity (90-99% ee, 13:1 to 99:1 dr).

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