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1.
Molecules ; 27(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35335150

RESUMO

The solvent extraction, complexing ability, and basicity of tetradentate N-donor 2,9-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-1,10-phenanthroline (CyMe4-BT- Phen) and its derivatives functionalized by Br, hydroxyphenyl, nitryl were discussed and compared. It was demonstrated that four BTPhen ligands are able to selectively extract Am(lll) over Eu(lll). It was notable that the distribution ratio of 5-nitryl-CyMe4-BTPhen for Eu(lll) was suppressed under 0.02, which was much lower compared to DEu(lll) = 1 by CyMe4-BTPhen. The analysis of the effect of the substituent on the affinity to lanthanides was conducted by UV/vis and fluorescence spectroscopic titration. The stability constants of various ligands with Eu(lll) were obtained by fitting titration curve. Additionally, the basicity of various ligands was determined to be 3.1 ± 0.1, 2.3 ± 0.2, 0.9 ± 0.2, 0.5 ± 0.1 by NMR in the media of CD3OD with the addition of DClO4. The basicity of ligands follows the order of L1 > L2 > L3 > L4, indicating the tendency of protonation decreases with the electron-withdrawing ability increase.

2.
ChemMedChem ; 16(13): 2130-2145, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-33755334

RESUMO

Novel chiral ionone alkaloid derivatives were synthesized and their antimetastatic effects were evaluated in human breast cancer cells using chemotaxis assay. Compared with positive control LY294002, a PI3 K inhibitor, derivatives 10 a, 11 a, 11 c, 11 g, 11 j, 11 k and 11 w exhibited significant inhibitory effects against cancer cell migration. Especially, the IC50 for compound 11 g was as low as 0.035±0.004 µM. Further investigations on compound 11 g revealed that it could exert inhibitory effects on the adhesion, migration and invasion of MDA-MB-231 cells. The mechanisms for the antitumor metastatic effects of 11 g might be through the inhibition of HIF-1α/VEGF/VEGFR2/Akt pathway, which suppressed the downstream signaling molecules, including Akt1/mTOR/p70S6K and Akt2/PKCζ/integrin ß1 pathways. Taken together, chiral ionone alkaloid derivative 11 g has the potential to be developed into an antitumor metastatic agent for breast cancer.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Descoberta de Drogas , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Norisoprenoides/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Alcaloides/síntese química , Alcaloides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Estrutura Molecular , Norisoprenoides/síntese química , Norisoprenoides/química , Relação Estrutura-Atividade , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 45(9): 2031-2035, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32495549

RESUMO

The long-term and extensive use of chemical fertilizers and pesticides in the cultivation of Chinese materia medica has resulted in serious soil ecological and environmental problems such as secondary salinization, soil consolidation, soil acidification, continuous cropping obstacles, micro-ecological imbalance, and serious soil pests and diseases in the production areas of Chinese materia medica. Therefore, promoting the ecological planting of Chinese materia medica is the only way for the production of Chinese materia medica. Attapulgite(ATP) is a kind of water-rich magnesium-rich aluminosilicate clay mineral with layered and chain structure. It has abundant reserves in China, possesses nano-material properties, strong adsorption and ion exchange properties, and has huge high value utilization space. ATP and its functional products have the potential of water and fertilizer conservation, regulating soil structure and micro-ecology, and are widely used in ecological planting of Chinese materia medica. This paper reviews the resource distribution, structural characteristics, the research and application progress in soil ecological effects of ATP, and prospects the application prospects of it in the ecological planting of Chinese materia medica.


Assuntos
Medicamentos de Ervas Chinesas , Materia Medica , China , Compostos de Magnésio , Medicina Tradicional Chinesa , Compostos de Silício , Solo
4.
Fitoterapia ; 142: 104499, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058049

RESUMO

3-O-[(E)-4-(4-cyanophenyl)-2-oxobut-3-en-1-yl] kaempferol is a novel lead compound to discover anti-diabetic and anti-obesity drugs. The present study reported the scaffold hopping of the lead compound to obtain a new isoxazole derivative, C45, which has improved glucose consumption at the nanomolar level (EC50 = 0.8 nM) in insulin resistant (IR) HepG2 cells. Western blotting showed that C45 markedly enhanced the phosphorylation of AMPK (AMP-activated protein kinase) and reduced the levels of the gluconeogenesis key enzymes PEPCK (phosphoenolpyruvate carboxykinase) and G6Pase (glucose 6-phosphatase) in HepG2 cells. The potential molecular mechanism of C45 may be activation of the AMPK/PEPCK/G6Pase pathways. We concluded that C45 might be a valuable candidate to discover anti-diabetic drugs.


Assuntos
Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Flavonoides/química , Glucose/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hipoglicemiantes/química , Estrutura Molecular
5.
Environ Sci Pollut Res Int ; 26(20): 20352-20363, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31102229

RESUMO

Methane (CH4) is an important greenhouse gas (GHG), and paddy fields are major sources of CH4 emissions. This pot experiment was conducted to investigate the integrated effects of Azolla inoculation combined with water management and N fertilization on CH4 emissions in a double-rice cropping system of Southern China. Results indicated that midseason aeration reduced total CH4 emissions by 46.9%, 38.6%, and 42.4%, followed by N fertilization with 32.5%, 17.0%, and 29.5% and Azolla inoculation with 32.5%, 17.0%, and 29.5%, on average, during the early, late, and annual rice growing seasons, respectively. The CH4 flux peaks and total CH4 emissions observed in the late rice growing season were significantly higher than those in the early rice growing season. Additionally, CH4 fluxes correlated negatively to soil redox potential (Eh) and dissolved oxygen (DO) concentration. Azolla inoculation and N fertilization greatly increased the rice grain yields, whereas midseason aeration had distinct effects on grain yields in both rice seasons. The highest annual rice grain yields of approximately 110 g pot-1 were obtained in the Azolla inoculation and N fertilization treatments. In terms of yield-scaled CH4 emission, Azolla inoculation combined with midseason aeration and N fertilization generated the lowest yield-scaled CH4 emissions both in the early and in the late rice growing seasons, as well as during the annual rice cycle. In contrast, the highest yield-scaled CH4 emission was obtained in the treatment employed continuous flooding, without Azolla and no N application. Our results demonstrated that Azolla inoculation, midseason aeration, and N fertilization practices mitigated total CH4 emissions by 18.5-42.4% during the annual rice cycle. We recommend that the combination of Azolla inoculation, midseason aeration, and appropriate N fertilization can achieve lower CH4 emissions and yield-scaled CH4 emissions in the double-rice growing system.


Assuntos
Agricultura/métodos , Gleiquênias , Fertilizantes , Metano/análise , Oryza/crescimento & desenvolvimento , China , Gases de Efeito Estufa/análise , Nitrogênio , Estações do Ano
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1392-7, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26415466

RESUMO

Cu in navel orange was detected rapidly by laser-induced breakdown spectroscopy (LIBS) combined with partial least squares (PLS) for quantitative analysis, then the effect on the detection accuracy of the model with different spectral data ptetreatment methods was explored. Spectral data for the 52 Gannan navel orange samples were pretreated by different data smoothing, mean centralized and standard normal variable transform. Then 319~338 nm wavelength section containing characteristic spectral lines of Cu was selected to build PLS models, the main evaluation indexes of models such as regression coefficient (r), root mean square error of cross validation (RMSECV) and the root mean square error of prediction (RMSEP) were compared and analyzed. Three indicators of PLS model after 13 points smoothing and processing of the mean center were found reaching 0. 992 8, 3. 43 and 3. 4 respectively, the average relative error of prediction model is only 5. 55%, and in one word, the quality of calibration and prediction of this model are the best results. The results show that selecting the appropriate data pre-processing method, the prediction accuracy of PLS quantitative model of fruits and vegetables detected by LIBS can be improved effectively, providing a new method for fast and accurate detection of fruits and vegetables by LIBS.


Assuntos
Citrus sinensis/química , Cobre/análise , Frutas/química , Análise Espectral , Lasers , Análise dos Mínimos Quadrados , Modelos Teóricos
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