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1.
Org Biomol Chem ; 20(9): 1982-1993, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35179157

RESUMEN

A cascade spiroannulation of 2-mercaptoquinoline-3-carbaldehydes with α,α-dicyanoalkenes as well as a cascade spiroannulation of 2-mercaptoquinoline-3-carbaldehydes aldehydes with α-bromocarbonyl compounds was investigated based on a synergistic strategy, providing a series of diverse spiro-fused heterocyclic compounds containing more different functional groups. The features of this strategy directed towards molecular complexity and diversity include step economy, mild conditions, and high bond-forming efficiency, but important polycyclic heterocyclic products, which could be transformed into potential biologically interesting heterocyclic structures.

2.
J Org Chem ; 85(18): 11934-11941, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32815368

RESUMEN

A novel and efficient approach to the synthesis of benzimidazo[2,1-b]thiazoline derivatives has been developed through an addition/cyclization/intramolecular oxidative C-H functionalization process. A variety of alkylene benzimidazo[2,1-b] thiazolines were conveniently assembled from the reaction of aryl isothiocyanate and propargylic amine in the presence of Cu(OAc)2 and PIFA at room temperature. The product could be further converted to substituted benzimidazo[2,1-b]thiazole derivatives.

3.
J Org Chem ; 85(12): 7793-7802, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32469521

RESUMEN

Based on a novel umpolung strategy, an efficient and highly enantioselective cascade aldol/cyclization/tautomerization of the 2-(2-oxoindolin-3-yl)malononitrile to active carbonyl compounds with excellent diastereo- and enantioselectivity has been developed. Also, various enantio-enriched multifunctional dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles with adjacent spiro-stereocenters were conveniently obtained by this novel methodology. Also, the dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles were easily transformed into structurally complex molecules without any effect on the diastereo- and enantioselectivity.

4.
J Org Chem ; 83(4): 2219-2226, 2018 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-29363980

RESUMEN

An efficient, mild, and substrate/catalyst-controlled chemoselective reaction of o-isothiocyanato-(E)-cinnamaldehyde with amines has been established, producing three types of six-membered heterocycles: 2-(4H-benzo[d][1,3]thiazin-4-yl)acetaldehydes, 2-(2-thioxo-1,2,3,4-tetrahydroquinazolin-4-yl)acetaldehydes, and (E)-4-(2-methoxyvinyl)-4H-benzo[d][1,3]thiazines. The reaction scopes were quite broad and excellent yield was achieved. This method is extremely efficient and practical and can be conducted on a gram-scale with slightly inferior reactivity under catalyst-free conditions at low cost, making it an ideal alternative to existing methods.

5.
J Org Chem ; 82(4): 2205-2210, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28103439

RESUMEN

A tandem Michael-Henry reaction of 2-mercaptoquinoline-3-carbaldehydes with nitroolefins using hydrogen-bonding-based cooperative organocatalysts for the highly diastereodivergent synthesis of chiral functionalized 3,4-dihydro-2H-thiopyrano[2,3-b]quinolines with three contiguous tertiary stereocenters has been developed.

6.
J Org Chem ; 81(9): 3553-9, 2016 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-27088573

RESUMEN

An organocatalytic enantioselective domino α-amination/oxidative coupling/cyclization of thioamides to azodicarboxylates catalyzed by an easily available organic catalyst has been developed. The key step, oxidative coupling, is smoothly fulfilled in air. Optically active spiroannulated 1,2,3-thiadiazole derivatives are obtained with high yields and enantioselectivities for the first time.

7.
J Org Chem ; 81(3): 1216-22, 2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26741047

RESUMEN

An efficient, mild, and convenient method for the preparation of 2,3-dihydrothieno(2,3-b)quinolines and thieno(2,3-b)-quinolines via an unexpected domino aza-Morita-Baylis-Hillman/alkylation/aldol reaction has been developed. The plausible mechanisms for the unexpected reaction are also given.

8.
J Org Chem ; 81(5): 1778-85, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26872395

RESUMEN

A copper-catalyzed and microwave-assisted synthesis of fully substituted pyrroles has been developed. A series of pentasubstituted pyrroles, especially α-arylpyrroles, could be obtained in moderate to good yields (up to 93%) through a tandem propargylation/alkyne azacyclization/isomerization sequence from readily available ß-enamino compounds and propargyl acetates.

9.
J Org Chem ; 80(22): 11521-8, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26474033

RESUMEN

A formal thio [3+2] cyclization catalyzed by Takemoto's organocatalyst has been reported for the construction of optically active spiroannulated dihydrothiophenes in high yields with excellent regio-, chemo-, diastereo-, and enantioselectivities.

10.
Org Biomol Chem ; 13(17): 4967-75, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25820179

RESUMEN

A series of spirooxindole tetrahydrofuran derivatives 3 were obtained in moderate to good yields via oxindole derivatives 1 and ß-arylacrylonitrile derivatives 2via base-mediated cascade [3 + 2] double Michael reactions under mild conditions and the application of this method in the synthesis of bioactive analogues, such as functionalized spirooxindole octahydrofuro[3,4-c]pyridine derivatives 4 which contain two new heterocyclic rings and two quaternary carbon centers, has also been developed. Subsequently, antifungal activities of all of the synthesized compounds were evaluated against five phytopathogenic fungi (Rhizoctonia solani, Fusarium semitectum, Alternaria solani, Valsa mali and Fusarium graminearum) using the mycelium growth rate method. The preliminary results showed that the spirooxindole octahydrofuro[3,4-c]pyridine derivative 4 showed higher growth inhibition of Valsa mali and Fusarium graminearum, than spirooxindole tetrahydrofuran derivatives 3. For example, spirooxindole octahydrofuro[3,4-c]pyridine derivative 4ab, having a bromine atom at the meta position of the benzene ring, was the best compound in inhibiting F. g. with an IC50 value of 3.31, in particular with inhibition of 4ab on F. g. being similar to that of the control cycloheximide (IC50 = 3.3 µg mL(-1)).


Asunto(s)
Antifúngicos/farmacología , Compuestos Heterocíclicos/farmacología , Indoles/farmacología , Compuestos de Espiro/farmacología , Alternaria/efectos de los fármacos , Alternaria/crecimiento & desarrollo , Antifúngicos/síntesis química , Antifúngicos/química , Relación Dosis-Respuesta a Droga , Fusarium/efectos de los fármacos , Fusarium/crecimiento & desarrollo , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Indoles/síntesis química , Indoles/química , Pruebas de Sensibilidad Microbiana , Oxindoles , Rhizoctonia/efectos de los fármacos , Rhizoctonia/crecimiento & desarrollo , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química
11.
Food Chem ; 444: 138553, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38309075

RESUMEN

The prohibition of antipsychotic drugs in animal foodstuffs has raised significant concerns. In this study, a novel matrix purification adsorbent comprising a polymer (polyaniline and polypyrrole)-functionalized melamine sponge (Ms) was employed for the high performance liquid chromatography-diode array detector (HPLC-DAD) detection of three phenothiazines (chlorpromazine, thioridazine, and promethazine), and a tricyclic imipramine in milk. The as-prepared functionalized Ms was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle measurements. Excellent linearity with a coefficient of determination (R2) of 0.999 was achieved for all drugs within the concentration range of 0.01-47.00 µg mL-1. The recoveries of the four analytes ranged from 92.1 % to 106.9 % at the three spiked levels. These results demonstrate the successful application of the proposed method for the determination of the four drugs. Cost-effective polymer-functionalized Ms is a viable alternative for matrix purification, enabling rapid determination of drug residues in diverse food samples.


Asunto(s)
Antipsicóticos , Leche , Triazinas , Animales , Leche/química , Cromatografía Líquida de Alta Presión/métodos , Polímeros/química , Pirroles/análisis , Extracción en Fase Sólida/métodos
12.
Phytomedicine ; 130: 155546, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38833790

RESUMEN

BACKGROUND: Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia, and its increasing prevalence is a global concern. Early diagnostic markers and therapeutic targets are essential for DM prevention and treatment. Pueraria, derived from kudzu root, is used clinically for various symptoms, and its active compound, Puerarin, shows promise in improving insulin resistance and reducing inflammation. PURPOSE: This study aims to evaluate the protective effects of metformin and Puerarin at different doses in an STZ-induced DM mouse model. The intricate metabolites within the serum of STZ-induced diabetic mice were subjected to thorough investigation, thus elucidating the intricate mechanism through which Puerarin demonstrates notable efficacy in the treatment of diabetes. METHODS: An STZ-induced DM mouse model is established. Mice are treated with metformin and puerarin at varying doses. Physiological, biochemical, and histomorphological assessments are performed. Metabolomics analysis is carried out on serum samples from control, DM, metformin, and medium-dose Puerarin groups. Western blot and qRT-PCR technologies are used to validate the mechanisms. RESULTS: The DM mouse model replicates abnormal blood glucose, insulin levels, physiological, biochemical irregularities, as well as liver and pancreas damage. Treatment with metformin and Puerarin restores these abnormalities, reduces organ injury, and modulates AMPK, PPARγ, mTOR, and NF-κB protein and mRNA expression. Puerarin activates the AMPK-mTOR and PPARγ-NF-κB signaling pathways, regulating insulin signaling, glucolipid metabolism, and mitigating inflammatory damage. CONCLUSION: This study demonstrates that Puerarin has the potential to treat diabetes by modulating key signaling pathways. The focus was on the finding that Puerarin has been shown to improve insulin signaling, glucolipid metabolism and attenuate inflammatory damage through the modulation of the AMPK-mTOR and PPARγ-NF-κB pathways. The discovery of Puerarin's favorable protective effect and extremely complex mechanism highlights its prospect in the treatment of diabetes and provides theoretical support for its comprehensive development and utilization.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Glucemia , Diabetes Mellitus Experimental , Hipoglucemiantes , Isoflavonas , Metformina , FN-kappa B , PPAR gamma , Pueraria , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , Isoflavonas/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , FN-kappa B/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Metformina/farmacología , PPAR gamma/metabolismo , Pueraria/química , Ratones , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Metabolómica , Insulina/sangre , Insulina/metabolismo
13.
Int J Biol Macromol ; 262(Pt 1): 129856, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38423908

RESUMEN

In this study, a novel polysaccharide, AAP-2S, was extracted from Auricularia auricula, and the anti-glycosylation effect of AAP-2S and its underlying mechanisms were investigated using an in vitro BSA-fructose model and a cellular model. The results demonstrated the inhibiting formation of advanced glycation end products (AGEs) in vitro by AAP-2S. Concurrently, it attenuated oxidative damage to proteins in the model, preserved protein sulfhydryl groups from oxidation, reduced protein carbonylation, prevented structural alterations in proteins, and decreased the formation of ß-crosslinked structures. Furthermore, AAP-2S demonstrated metal-chelating capabilities. GC-MS/MS-based metabolomics were employed to analyze changes in metabolic profiles induced by AAP-2S in a CML-induced HK-2 cell model. Mechanistic investigations revealed that AAP-2S could mitigate glycosylation and ameliorate cell fibrosis by modulating the RAGE/TGF-ß/NOX4 pathway. This study provides a foundational framework for further exploration of Auricularia auricular polysaccharide as a natural anti-AGEs agent, paving the way for its potential development and application as a food additive.


Asunto(s)
Auricularia , Reacción de Maillard , Auricularia/metabolismo , Espectrometría de Masas en Tándem , Polisacáridos/farmacología , Proteínas , Productos Finales de Glicación Avanzada/metabolismo
14.
J Acoust Soc Am ; 133(3): 1827-34, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23464051

RESUMEN

Gene therapy by intratumoral injection is a promising approach for treating solid tumors. However, this approach has limited success due to insufficient distribution of gene vectors used for gene delivery. Previous studies have shown that pulsed-focused ultrasound (pFUS) can enhance both systemic and local delivery of therapeutic agents in solid tumors and other disease models. Here, murine squamous cell carcinoma flank tumors were treated with single intratumoral injection of naked tumor necrosis factor-alpha (TNF-α) plasmid, either with or without a preceding pFUS exposure. The exposures were given at 1 MHz, at a spatial average, temporal peak intensity of 2660 W cm(-2), using 50 ms pulses, given at a pulse repetition frequency of 1 Hz. One hundred pulses were given at individual raster points, spaced evenly over the projected surface of the tumor at a distance of 2 mm. Exposures alone had no effect on tumor growth. Significant growth inhibition was observed with injection of TNF-α plasmid, and tumor growth was further inhibited with pFUS. Improved results with pFUS correlated with larger necrotic regions in histological sections and improved distribution and penetration of fluorescent surrogate nanoparticles. Electron microscopy demonstrated enlarged gaps between cells in exposed tissue, and remote acoustic palpation showed decreases in tissue stiffness after pFUS. Combined, these results suggest pFUS effects may be reducing barriers for tissue transport and additionally lowering interstitial fluid pressure to further improve delivery and distribution of injected plasmid for greater therapeutic effects. This suggests that pFUS could potentially be beneficial for improving local gene therapy treatment of human malignancies.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Terapia Genética , Neoplasias de los Tejidos Blandos/terapia , Factor de Necrosis Tumoral alfa/biosíntesis , Ultrasonido , Acústica , Animales , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/ultraestructura , Femenino , Humanos , Ratones , Ratones Endogámicos C3H , Microscopía Electrónica de Transmisión , Necrosis , Palpación , Permeabilidad , Neoplasias de los Tejidos Blandos/genética , Neoplasias de los Tejidos Blandos/inmunología , Neoplasias de los Tejidos Blandos/ultraestructura , Tejido Subcutáneo/inmunología , Tejido Subcutáneo/ultraestructura , Factores de Tiempo , Carga Tumoral , Factor de Necrosis Tumoral alfa/genética
15.
Front Cell Infect Microbiol ; 13: 1151557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37180438

RESUMEN

Non-small cell lung cancer (NSCLC) is one of the most serious diseases affecting human health today, and current research is focusing on gut flora. There is a correlation between intestinal flora imbalance and lung cancer, but the specific mechanism is not clear. Based on the "lung and large intestine being interior-exteriorly related" and the "lung-intestinal axis" theory. Here, based on the theoretical comparisons of Chinese and western medicine, we summarized the regulation of intestinal flora in NSCLC by active ingredients of traditional Chinese medicine and Chinese herbal compounds and their intervention effects, which is conducive to providing new strategies and ideas for clinical prevention and treatment of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Neoplasias Pulmonares , Humanos , Medicina Tradicional China , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico
16.
J Agric Food Chem ; 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36753681

RESUMEN

Eucommia bark contains many bioactive compounds and has anti-hyperlipidemic effects. However, due to the slow growth rate of the plant, there is a limited supply of this resource. Studies have demonstrated that Eucommia leaves contain active ingredients similar to those of Eucommia bark and also have anti-hyperlipidemic effects. It is not currently clear whether Eucommia leaf can be used as a substitute for Eucommia bark. Furthermore, their mechanism of action for anti-hyperlipidemia by improving the structure of the gut microbiota is also unclear. We aimed to determine the composition of the active ingredients in EBE and ELE by HPLC, establish an HFD-induced hyperlipidemia model, and combine fecal microbiota transplantation (FMT) experiments to investigate the mechanism of EBE/ELE anti-hyperlipidemia by modifying the structure of intestinal microbiota, as well as to compare the effects of EBE and ELE. Our results showed that EBE and ELE contained similar active ingredients and significantly alleviated lipid metabolism disorders and blood glucose levels in the HFD-induced hyperlipidemia model. In this study, EBE and ELE significantly reduced the relative abundance of Desulfovibrionaceae and Erysipelotrichaceae and significantly increased the relative abundance of Ruminococcaceae. They also promoted the production of short-chain fatty acids (SCFAs) and activated the gene expression of the SCFA receptors G protein-coupled receptor 41 (GPR41) and GPR43. In addition, EBE and ELE can significantly increase the expression of the fasting-induced adipose factor (Fiaf) gene in the colon and inhibit the secretion of lipoprotein lipase (LPL) in the liver, thereby inhibiting triglyceride (TG) synthesis. They also significantly activate the expression of GPR41 and GPR43 genes in the epididymal fat tissue, leading to reduced lipid accumulation in adipocytes. These effects on the target genes were associated with changes in the abundance of Desulfovibrionaceae, Erysipelotrichaceae, and Ruminococcaceae bacteria in the intestinal microbiota. Thus, regulating the relative abundance of these microbes may serve as prospective targets for EBE/ELE to influence the Fiaf-LPL gut-liver axis and the SCFAs-GPR41/GPR43 gut-fat axis. In addition, there was no significant difference in the anti-hyperlipidemic effects of ELE and EBE, suggesting that Eucommia leaf may be a suitable alternative to Eucommia bark for managing hyperlipidemia by regulating the structure of the intestinal microbiota. These findings suggest that Eucommia leaves have great potential for development as a functional food with lipid-lowering properties.

17.
Foods ; 12(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37297378

RESUMEN

From Siraitia grosvenorii, a natural polysaccharide named SGP-1 was discovered, and its purity was determined to be 96.83%. Its structure is a glucan with 4-, 6- and 4,6-linked glucose units. In this paper, the sulfated derivative S-SGP of SGP-1 was prepared by the chlorosulfonic acid method. The sulfated derivatives were analyzed by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and scanning electron microscopy (SEM). The degree of substitution (DS) of the polysaccharide is 0.62, and the weight average molecular weight (Mw) is 1.34 × 104 Da. While retaining the morphological characteristics of polysaccharides, S-SGP appeared a large number of spherical structures and strong intermolecular forces. The in vitro activity study of S-SGP showed that the sulfated derivatives had the ability to scavenge DPPH radicals, hydroxyl radicals and superoxide anions, and the scavenging power tended to increase with the increase in polysaccharide concentration. It can inhibit the growth of human hepatoma cells (HepG2), human breast cancer cells (MDA-MB-231) and human non-small cell lung cancer cells (A549) in vitro. In addition, the treatment of A549 cells with sulfuric acid derivatives can decrease the mitochondrial membrane potential, induce apoptosis, and alter the expression of apoptosis-related mRNA and protein.

18.
Foods ; 12(18)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37761137

RESUMEN

Lipid accumulation causes diseases such as obesity and abnormal lipid metabolism, thus impairing human health. Tea polysaccharide is one of the natural, active substances that can lower lipid levels. In this paper, an oleic-acid-induced HepG2 cell model was established. The lipid-lowering effects of a novel group of Fuzhuan brick tea polysaccharides (FTPs)-obtained from Fuzhuan brick tea-were examined in vitro. The monosaccharide composition of FTP3 was Glc, Gal, Ara, Man, Rha, GalAc, GlcAc, and Xyl with a molar ratio of 23.5:13.2:9.0:5.5:5.4:2.7:1.3:1.0, respectively. A molecular weight of 335.68 kDa was identified for FTP3. HepG2 cells treated with FTP3 achieved a prominent lipid-lowering effect compared with cells treated with oleic acid. Images of the Oil Red O staining treatment showed that FTP3-treated groups had significantly fewer red fat droplets. TC and TG levels were lower in FTP3-treated groups. FTP3 alleviated lipid accumulation in HepG2 cells, activated AMPK, and decreased the SREBP-1C and FAS protein expressions associated with fatty acid synthesis. FTP3 holds promising potential for its lipid-lowering effects.

19.
Org Biomol Chem ; 10(42): 8471-7, 2012 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-23001215

RESUMEN

A highly regio-, chemo-, diastereo- and enantioselective organocatalytic [4 + 1] annulation of 2-halo-1,3-dicarbonyl compounds with Morita-Baylis-Hillman adducts catalyzed by commercially available, low cost quinidine for the preparation of synthetically unique and medicinally multi-functionalized isoxazoline N-oxides with three stereogenic centers including adjacent quaternary and tertiary stereocenters has been developed. Notably, the unexpected product ethyl 2-((tert-butyldimethylsilyl)oxy)-2-(5,5-diacetyl-3-((methylsulfonyl)oxy)-4-phenylisoxazolidin-3-yl)acetate (8) bearing a quaternary stereocenter and two tertiary stereocenters was obtained from the undocumented 5,5-diacetyl-3-(2-ethoxy-1-hydroxy-2-oxoethyl)-4-phenyl-4,5-dihydroisoxazole 2-oxide (4ba).


Asunto(s)
Isoxazoles/química , Óxidos/química , Quinidina/química , Catálisis , Isoxazoles/síntesis química , Modelos Moleculares , Óxidos/síntesis química , Estereoisomerismo
20.
Org Biomol Chem ; 10(32): 6554-61, 2012 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-22760526

RESUMEN

A series of functionalized 2,3-dihydro-1,4-benzoxazines were obtained in moderate to excellent yields via domino [5 + 1] annulations of 2-halo-1,3-dicarbonyl compounds 2 with imines 1 under mild conditions and the application of this method in the synthesis of bioactive analogues, such as functionalized tetracyclic-1,4-benzoxazines which contain two new heterocyclic rings and one quaternary carbon center has also been developed.


Asunto(s)
Benzoxazinas/síntesis química , Halógenos/química , Iminas/química , Benzoxazinas/química , Química Farmacéutica , Cristalografía por Rayos X , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Estructura Molecular
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