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1.
J Chromatogr A ; 1604: 460471, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31471133

RESUMO

The influence of chlorine substituents in chiral separation of three racemic 2-(chlorophenyl)propanoic acids by countercurrent chromatography using hydroxypropyl-ß-cyclodextrin as a chiral additive were mainly investigated in the present paper, including 2-(2-chlorophenyl)propanoic acids, 2-(3-chlorophenyl)propanoic acids and 2-(4-chlorophenyl)propanoic acids. The influences of chromatographic conditions on the retention behavior were studied by enantioselective liquid-liquid extraction experiments using the methodology of response surface It was found that 2-(3-chlorophenyl)propanoic acids could be successfully chiral separated by countercurrent chromatography, while no resolution was achieved for racemic 2-(2-chlorophenyl)propanoic acids and 2-(4-chlorophenyl)propanoic acids under optimized separation conditions. The formation of 1:1 stoichiometric inclusion compounds between 2-(3-chlorophenyl)propanoic acids and HP-ß-CD was determined by UV spectra measurements. The inclusion constants for 2-(3-chlorophenyl)propanoic acids and HP-ß-CD were determined by the Benesi-Hildebrand equation. Meanwhile, the inclusion constants of 2-(3-chlorophenyl)-propanoic acid enantiomer and HP-ß-CD were obtained by the pesudophase retention equation in countercurrent chromatography. Furthermore, the inclusion interactions of the three racemates with HP-ß-CD were also investigated by the molecular docking. The results obtained from UV spectra measurements and molecular docking showed that the racemate with chlorine substituents in meta-position presented the highest enantiorecognition while the racemates with chlorine substituents in ortho-position had the lowest enantiorecognition. The above results further indicated that forming a stable inclusion complex between racemate and chiral selector is a prerequisite for a successful enantioseparation and at the same time, the difference in inclusion capacity between the two enantiomers is also essential for the enantioseparation.


Assuntos
Técnicas de Química Analítica/métodos , Cloro/análise , Distribuição Contracorrente , Propionatos/isolamento & purificação , 2-Hidroxipropil-beta-Ciclodextrina/análise , Extração Líquido-Líquido , Simulação de Acoplamento Molecular , Propionatos/análise , Estereoisomerismo
2.
Acta Biochim Biophys Sin (Shanghai) ; 51(9): 925-933, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31435637

RESUMO

In study, we aimed to determine the mechanisms underlying the gastroprotective effects of sodium copper chlorophyllin (SCC) against ethanol-induced gastric ulcer injury in mice. First, the gastroprotective effects of SCC against gastric ulcer induced by ethanol were assessed. Then, biochemical, histopathological, immunohistochemistry assays, and western blot analysis were conducted to determine the possible mechanisms of action underlying the effects of SCC. Compared to the effects of omeprazole (OME) in a confirmed mouse model of ethanol-induced gastric ulcer injury, treatment with various doses of SCC resulted in up-regulation of Bcl-2 and down-regulation of the pro-apoptotic protein Bax. Significant decreases in the levels of the malondialdehyde (MDA), myeloperoxidase (MPO), and NO in the gastric tissues were observed. Furthermore, inflammatory cytokine analysis revealed that SCC treatment inhibited the expressions of TNF-α and IL-6, greatly reduced the phosphorylation level of IκB, and repressed the nuclear translocation of NF-κB p65, which demonstrated that SCC inhibited the activation of the NF-κB pathway. The present findings suggest that the protective effects of SCC may be beneficial as a potential preventive and therapeutic agent for gastric ulcer through the NF-κB pathway. Taken together, SCC administration significantly decreased the levels of MPO, NO, and MDA in gastric tissue and exerted a powerful anti-inflammatory activity as demonstrated by reduction in the secretions of proinflammatory mediators such as IL-6 and TNF-α in the serum of mice exposed to ethanol.

3.
J Sep Sci ; 42(18): 3009-3015, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31309721

RESUMO

A novel on-line synergistic proconcentration strategy coupling field-amplified sample stacking and micelle to cyclodextrin stacking for cationic analytes in capillary zone electrophoresis has been proposed and applied for the separation and determination of two alkaloids, matrine, and oxymatrine in complicated matrix samples. The approach was performed by the long injection of sample in a low-conductivity sodium dodecyl benzene sulfonate solution followed by the injection of hydroxypropyl-ß-cyclodextrin solution in higher conductivity. The stacking mechanism of this method has been expounded and parameters affecting stacking effect have been optimized in our study. Under the optimum experimental conditions, 169- and 218-fold sensitivity improvements were achieved for matrine and oxymatrine when compared with normal injection. Analytical indicators including linearity, limits of detection, and reproducibility (intra- and inter-day relative standard deviations) were evaluated. Moreover, sample matrix effect was studied using compound flavescent sophora and salicylic acid powder and spiked urine samples. The developed method is an attempt for the combination of micelle to cyclodextrin stacking with other stacking methods. It could be a good alternative choice for the determination of alkaloids in a complex sample matrix.

4.
Fitoterapia ; 137: 104190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163199

RESUMO

The genus Tripterygium belongs to the family Celastraceae, and contains three species, i.e. Tripterygium wilfordii Hook. F, Tripterygium hypoglaucum (Levl.) Hutch. and Tripterygium regelii Sprague et Takeda. All three species are reported to have excellent medicinal properties that help to cure rheumatoid arthritis, nephrotic syndrome, systemic lupus erythematosus and widely used as a folk medicine in China. Phytochemical studies have led to discovering more than 500 secondary metabolites in this genus, including five main types: sesquiterpenoids, diterpenes, triterpenoids, flavonoids, lignans. This work provides structurally grouping statistic of 198 secondary metabolites of Tripterygium species published from 2008 to the present, as well as pharmacological knowledges in the past five years. The information will be helpful for developing the new discoveries of medicinal value related to the genus Tripterygium.


Assuntos
Tripterygium/química , Tripterygium/classificação , Animais , Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antivirais/química , Diterpenos/química , Flavonoides/química , Humanos , Imunossupressores/química , Lignanas/química , Estrutura Molecular , Fármacos Neuroprotetores/química , Compostos Fitoquímicos/química , Metabolismo Secundário , Sesquiterpenos/química , Triterpenos/química
5.
J Chromatogr A ; 1570: 99-108, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30097343

RESUMO

Racemic trans-paroxol, trans-N-methylparoxetine and trans-paroxetine containing two chiral centres were stereoselectively separated using countercurrent chromatography with hydroxypropyl-ß-cyclodextrin as the chiral selector. A two-phase solvent system composed of n-butyl acetate and 0.1 mol L-1 sodium carbonate-sodium bicarbonate buffer at pH 9.2 (1:1, v/v) was selected, and 0.10 mol L-1 hydroxypropyl-ß-cyclodextrin was added to the aqueous phase as the chiral selector. Racemic trans-N-methylparoxetine and racemic trans-paroxol (20 mg of each) were stereoselectively separated by countercurrent chromatography in an individual run, yielding 7.1-8.3 mg of enantiomers with a purity of 95-98%, where the recovery of each separated isomer reached approximately 70-83%. Racemic trans-paroxetine (20 mg) was stereoselectively separated by countercurrent chromatography using a recycling elution mode with a biphasic solvent system composed of n-hexane: n-butyl acetate: 0.1 mol L-1 sodium carbonate-sodium bicarbonate buffer at pH 9.2 (9:1:10, v/v/v), and 0.10 mol L-1 hydroxypropyl-ß-cyclodextrin was added to the aqueous phase as the chiral selector, yielding 5.0-5.6 mg of enantiomer with a high purity of over 98-99%.


Assuntos
Distribuição Contracorrente/métodos , Paroxetina/química , Paroxetina/isolamento & purificação , Inibidores de Captação de Serotonina/química , Inibidores de Captação de Serotonina/isolamento & purificação , Solventes/química , Estereoisomerismo
6.
J Org Chem ; 82(3): 1610-1617, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28034312

RESUMO

The metal-free cross-dehydrogenative coupling (CDC) reaction and subsequent cyclization of 2-hydroxy-1,4-naphthoquinone (lawsone) and 1,3-diarylpropene promoted by DDQ has been developed. 2-Hydroxy-3-alkyl-1,4-naphthoquinones and pyranonaphthoquinones with potential pharmaceutical applications are obtained in moderate to good yields. The reaction is also compatible for 4-hydroxycoumarins.

7.
Phytochemistry ; 119: 26-31, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26454794

RESUMO

Seven neo-clerodane diterpenes, teufruintins A-G (1-7), together with eight known compounds (8-15) were isolated from the CHCl3-soluble fraction of the aerial parts of Teucrium fruticans cultivated in China. The chemical structures of the isolated compounds were elucidated using different spectroscopic methods. All of the isolated diterpenes were evaluated for their cytotoxic activities on three human cancer cell lines, and for their ability to inhibit LPS-induced nitric oxide production in RAW 264.7 macrophages. None of the compounds displayed cytotoxic activities on the cancer cell lines, and only 15 showed weak NO inhibitory activity.


Assuntos
Diterpenos Clerodânicos , Medicamentos de Ervas Chinesas , Componentes Aéreos da Planta/química , Teucrium/química , Animais , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Diterpenos Clerodânicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Teucrium/genética
8.
Nat Prod Res ; 29(13): 1207-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25554101

RESUMO

Phytochemical investigation of the roots of Gypsophila oldhamiana afforded two new ß-carboline alkaloids, oldhamiaines A and B (1 and 2), along with a known analogue (3). Their structures were elucidated by using spectroscopic and chemical methods. This is the first report of ß-carboline alkaloids in the genus Gypsophila.


Assuntos
Alcaloides/química , Carbolinas/química , Caryophyllaceae/química , Raízes de Plantas/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular
9.
Chem Pharm Bull (Tokyo) ; 62(5): 472-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24789929

RESUMO

Two new neo-clerodane diterpenoids, teucvisins A and B (1, 2), and three new 19-nor-neoclerodane diterpenoids, teucvisins C-E (3-5), together with ten known constituents (6-15) were isolated from the whole plants of Teucrium viscidum. All the isolates were evaluated for their inhibitory activities of lipopolysaccharide (LPS)-induced nitric oxide production in RAW264.7 macrophages. The results indicated that compounds 11 and 15 showed moderate inhibition with an IC50 value of 21.9 and 22.4 µM, respectively.


Assuntos
Diterpenos Clerodânicos/farmacologia , Macrófagos/efeitos dos fármacos , Teucrium/química , Animais , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Relação Estrutura-Atividade
10.
J Nat Prod ; 77(2): 200-5, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24484201

RESUMO

Eight new glucosylated coumaroyltyramine derivatives, teuvissides A-H (1-8), were isolated from whole plants of Teucrium viscidum. Their structures were elucidated using spectroscopic data and chemical methods. The antihyperglycemic activities of these compounds were evaluated in HepG2 cells and 3T3-L1 adipocytes, and all of the isolates elicited different levels of glucose consumption at a concentration of 2.0 µM. Teuvissides A (1), B (2), and F (6) induced 2.2-, 2.1-, and 2.2-fold changes, respectively, in the levels of glucose consumption in HepG2 cells and 2.5-, 2.1-, and 2.3-fold changes, respectively, in 3T3-L1 adipocytes relative to the basal levels.


Assuntos
Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Teucrium/química , Tiramina/análogos & derivados , Adipócitos/efeitos dos fármacos , Animais , Ácidos Cumáricos/química , Medicamentos de Ervas Chinesas/química , Glucose/análogos & derivados , Glucose/farmacologia , Glicosídeos/química , Células Hep G2 , Humanos , Hipoglicemiantes/química , Insulina/farmacologia , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Tiramina/química , Tiramina/isolamento & purificação , Tiramina/farmacologia
11.
Nat Prod Res ; 28(3): 196-200, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24467362

RESUMO

A new neo-clerodane diterpene, named ajugacumbin J (1), together with 13 known compounds (2-14) was isolated from Ajuga decumbens. The structure of ajugacumbin J (1) was elucidated by 1D and 2D NMR spectra and MS. Ajugacumbin J (1) and ajugacumbin D (5) exhibited inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with an IC50 value of 46.2 and 35.9 µM, respectively.


Assuntos
Ajuga/química , Anti-Inflamatórios/isolamento & purificação , Diterpenos Clerodânicos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese
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