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1.
J Agric Food Chem ; 69(32): 9229-9237, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34357758

RESUMEN

The dried leaves and rhizomes of Alpinia zerumbet have been traditionally used as food and medicine. Anti-inflammatory activity-guided phytochemical investigation into the rhizomes of A. zerumbet led to the isolation of 17 compounds including 10 neolignans (1-10, 1a, 1b, 2a, 2b, 3a, 3b, 4, and 5 are new compounds) and seven diarylheptanoids (11-17) in which 1-3 were three pairs of enantiomers. 4 was only one enantiomer and 5 was a racemic mixture. Compounds 1a, 1b, 2a, and 2b incorporated an 8',9'-dinorneolignan skeleton, which was rare in the lignan family. The planar structures of these compounds were elucidated by extensive analyses of spectroscopic data. The relative and absolute configurations were determined by the time-dependent density functional theory (TDDFT)-based electronic circular dichroism (ECD) calculation method. The 95% ethanol extract and ethyl acetate extract of A. zerumbet were found to show anti-inflammatory activity against croton oil-induced ear edema in mice with inhibition rates of 20.0 and 47.6% at a dose of 80 mg/kg, respectively. Bioassays showed that compounds 1a, 1b, 2a, 2b, and 12 moderately inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 cells with IC50 values of 3.62, 7.63, 6.51, 5.60, and 8.33 µM, respectively.


Asunto(s)
Alpinia , Lignanos , Animales , Antiinflamatorios/farmacología , Diarilheptanoides , Lignanos/farmacología , Ratones , Estructura Molecular , Extractos Vegetales/farmacología , Rizoma
3.
Chem Commun (Camb) ; (41): 6174-6, 2009 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-19826659

RESUMEN

Hierarchical gamma-Al2O3 monoliths with interconnected macroporous architecture and highly ordered 2D hexagonal mesostructure have been synthesized by using nonionic triblock copolymer and polyurethane foam as co-templates.


Asunto(s)
Óxido de Aluminio/síntesis química , Óxido de Aluminio/química , Cristalización , Poliuretanos/síntesis química , Porosidad , Difracción de Rayos X
4.
J Am Chem Soc ; 130(11): 3465-72, 2008 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-18284238

RESUMEN

The facile synthesis of highly ordered mesoporous aluminas with high thermal stability and tunable pore sizes is systematically investigated. The general synthesis strategy is based on a sol-gel process associated with nonionic block copolymer as templates in ethanol solvent. Small-angle XRD, TEM, and nitrogen adsorption and desorption results show that these mesoporous aluminas possess a highly ordered 2D hexagonal mesostructure, which is resistant to high temperature up to 1000 degrees C. Ordered mesoporous structures with tunable pore sizes are obtained with various precursors, different acids as pH adjustors, and different block copolymers as templates. These mesoporous aluminas have large surface areas (ca. 400 m2/g), pore volumes (ca. 0.70 cm3/g), and narrow pore-size distributions. The influence of the complexation ability of anions and hydro-carboxylic acid, acid volatility, and other important synthesis conditions are discussed in detail. Utilizing this simple strategy, we also obtained partly ordered mesoporous alumina with hydrous aluminum nitrate as the precursor. FTIR pyridine adsorption measurements indicate that a large amount of Lewis acid sites exist in these mesoporous aluminas. These materials are expected to be good candidates in catalysis due to the uniform pore structures, large surface areas, tunable pore sizes, and large amounts of surface Lewis acid sites. Loaded with ruthenium, the representative mesoporous alumina exhibits reactant size selectivity in hydrogenation of acetone, D-glucose, and D-(+)-cellobiose as a test reaction, indicating the potential applications in shape-selective catalysis.


Asunto(s)
Óxido de Aluminio/síntesis química , Temperatura , Óxido de Aluminio/química , Cristalización , Etanol/química , Geles/química , Calor , Tamaño de la Partícula , Porosidad , Reproducibilidad de los Resultados , Propiedades de Superficie
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