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1.
Chemistry ; 21(3): 984-7, 2015 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-25430681

RESUMEN

Fluorescence-switch-based logic devices are very sensitive compared with most of the reported devices based on UV/Vis absorption systems. Herein, we demonstrate that a simple molecule, 5,10,15,20-tetra-(4-aminophenyl)porphyrin (TAPP), shows protonation-induced multiple emission switches through intramolecular charge transfer and/or aggregation-caused quenching. Highly sensitive INHIBIT and XOR logic gates can be achieved by combining the intermolecular assembly with the intramolecular photoswitching of diprotonated TAPP (TAPPH2(2+)). In addition, molecular simulations have been performed by DFT for a better understanding of the emission-switching processes.

2.
J Nat Prod ; 73(12): 1993-8, 2010 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-21090796

RESUMEN

The present investigation on the chemical constituents of the roots of Stellaria dichotoma var. lanceolata has resulted in the isolation of 21 ß-carboline alkaloids, including 13 new compounds, dichotomides III-XIV (1-12) and dichotomine E (13), and eight known compounds. The structures of the new compounds were established on the basis of spectroscopic data analysis. Among these isolated alkaloids, five compounds were examined for their anti-inflammatory potential for the inhibition of NO production in LPS-treated RAW 264.7 cells. All compounds tested exhibited significant inhibition of NO production, with IC(50) values in the range of 11.3 to 19.3 µM.


Asunto(s)
Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antiinflamatorios no Esteroideos/aislamiento & purificación , Antiinflamatorios no Esteroideos/farmacología , Carbolinas/aislamiento & purificación , Carbolinas/farmacología , Stellaria/química , Alcaloides/química , Animales , Antiinflamatorios no Esteroideos/química , Carbolinas/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Concentración 50 Inhibidora , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Raíces de Plantas , Estereoisomerismo , Taiwán
3.
J Vis Exp ; (131)2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29443091

RESUMEN

We present a method, the bacterial mineral excretion (BME), for synthesizing two kinds of microcapsules, sodium tungstate and sodium molybdate, and the two metal oxides' corresponding nanoparticles-the former being as small as 22 nm and the latter 15 nm. We fed two strains of bacteria, Shewanella algae and Pandoraea sp., with various concentrations of tungstate or molybdate ions. The concentrations of tungstate and molybdate were adjusted to make microcapsules of different length-to-diameter ratios. We found that the higher the concentration the smaller the nanoparticles were. The nanoparticles came in with three length-to-diameter ratios: 10:1, 3:1 and 1:1, which were achieved by feeding the bacteria respectively with a low concentration, a medium concentration, and a high concentration. The images of the hollow microcapsules were taken via the scanning electron microsphere (SEM). Their crystal structures were verified by X-ray diffraction (XRD)-the crystal structure of molybdate microcapsules is Na2MoO4 and that of tungstate microcapsules is Na2WO4 with Na2W2O7. These syntheses all were accomplished under a near ambient condition.


Asunto(s)
Burkholderiaceae/metabolismo , Molibdeno/metabolismo , Shewanella/metabolismo , Compuestos de Tungsteno/metabolismo , Cápsulas , Molibdeno/química , Nanopartículas/química , Nanopartículas/metabolismo , Compuestos de Tungsteno/química
4.
ACS Appl Mater Interfaces ; 8(20): 12588-93, 2016 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-27158976

RESUMEN

Swelling has great influences on the structure stability and separation performance of graphene oxide laminate membranes (GOLMs) for water desalination and purification. Herein, we report cross-linked GOLMs from GO assembled with cationic tetrakis(1-methyl-pyridinium-4-yl)porphyrin (TMPyP) by a vacuum-assisted strategy. The concave nonoxide regions (G regions) of GO are used as cross-linking sites for the first time to precisely control the channel size for water permeation and salt ion retention. Channels around 1 nm are constructed by modulating the assembly ratio of TMPyP/GO, and these cross-linked GOLMs show high salt rejection.

5.
J Nat Prod ; 69(1): 93-6, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16441075

RESUMEN

Nine new abietane diterpene alkaloids containing an oxazole ring, salviamines A-F (1-6) and isosalviamines C-E (7-9), together with 17 known abietane diterpenes, were isolated and characterized from the roots of Salvia yunnanensis. The structures of 1-9 were elucidated by interpretation of their spectroscopic data.


Asunto(s)
Abietanos/aislamiento & purificación , Alcaloides/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Oxazoles/aislamiento & purificación , Plantas Medicinales/química , Salvia/química , Abietanos/química , Alcaloides/química , Medicamentos Herbarios Chinos/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Oxazoles/química , Raíces de Plantas/química
6.
Chem Pharm Bull (Tokyo) ; 50(2): 157-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11848201

RESUMEN

Three new pavine N-oxide alkaloids, (-)-isocaryachine-N-oxide B, (+)-caryachine-N-oxide, (-)-caryachine-N-oxide, and a new isoquinoline alkaloid, 6,7-methylenedioxy-N-methylisoquinoline together with 11 known alkaloids were isolated and characterized from the stem bark of Cryptocarya chinensis. The structures of the isolated compounds were determined by spectral methods. The stereochemistry of pavine-N-oxide alkaloids is also discussed.


Asunto(s)
Alcaloides/aislamiento & purificación , Lauraceae/química , Alcaloides/química , Espectroscopía de Resonancia Magnética , Conformación Molecular
7.
Chem Pharm Bull (Tokyo) ; 52(3): 345-9, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14993759

RESUMEN

Three new compounds: begonanline (1). nantoamide (2). and methyl (S)-glycerate (3). as well as forty-four known compounds have been isolated and characterized from the rhizomes of Begonia nantoensis. The structures of these compounds were determined by spectral analyses and/or X-ray crystallography. Among them, cucurbitacin B (4). dihydrocucurbitacin B (5). cucurbitacin E (6). dihydrocucurbitacin E (7). cucurbitacin I (8). and (-)-auranamide (9). showed cytotoxicity against four human cancer cell lines. 3beta,22alpha-Dihydroxyolean-12-en-29-oic acid (10), indole-3-carboxylic acid (11), 5,7-dihydroxychromone (12), and (-)-catechin (13) demonstrated significant activity against HIV replication in H9 lymphocyte cells.


Asunto(s)
Fármacos Anti-VIH/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Begoniaceae/química , Benzamidas/aislamiento & purificación , Carbolinas/aislamiento & purificación , Ácidos Glicéricos/aislamiento & purificación , Plantas Medicinales/química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Benzamidas/química , Benzamidas/farmacología , Carbolinas/química , Carbolinas/farmacología , China , Cristalografía por Rayos X , Ácidos Glicéricos/química , Ácidos Glicéricos/farmacología , Humanos , Linfocitos/efectos de los fármacos , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Rizoma/química , Triterpenos/química , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Células Tumorales Cultivadas
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