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1.
Chem Commun (Camb) ; 58(39): 5861-5864, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35470361

RESUMO

LiTFSI/H2O water-in-salt electrolytes with different concentrations show high energy densities for capacitive charge storage at sub-zero-temperatures (e.g. 32.23, 38.35 and 35 W h kg-1 at 0, -10 and -20 °C, which are 1.44, 1.71 and 1.56 times that of normal temperature).

2.
Ultrason Sonochem ; 48: 127-135, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080535

RESUMO

Two new Ag(I) coordination polymers (CPs), namely, Ag(L)(Htp) (1) and [Ag(L)]·(Htp)·2H2O (2) were synthesized from the long flexible ligand of 1,6-bis(2-methylbenzimidazolyl)hexane (L), terephthalic acid (H2tp) and different silver(I) salts using hydrothermal and sonochemical methods, These CPs were characterized by elemental analysis, IR spectra, scanning electron microscopy, single-crystal and powder X-ray diffraction analysis. 1 features a uninodal 3-connected 2D hcb layered structure, while 2 exhibits an infinite 1D linear chain and ultimately extended into 3D supramolecular framework via O-H⋯O and Ag⋯O interactions. In addition, the effect of various sonication concentrations of the initial reagents, ultrasonic time and power of ultrasound irradiation on the size and morphology of nanostructured 1 and 2 were evaluated. Nano-sized 1 and 2 exhibit relatively high performance as UV light driven photocatalysts for the degradation of methylene blue.

3.
Springerplus ; 5: 333, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27066356

RESUMO

Coconut is a high-quality agricultural product of the Asia-Pacific region. In this paper, coconut shell which mainly composed of cellulose, hemicellulose, lignin was used as a raw material for coconut shell oil from coconut shell pyrolysis. The influence of the pyrolysis temperature, heating rate and particle size on coconut oil yield was investigated, and the effect of heating rate on coconut oil components was discussed. Experimental results show that the maximum oil yield of 75.74 wt% (including water) were obtained under the conditions that the final pyrolysis temperature 575 °C, heating rate 20 °C/min, coconut shell diameter about 5 mm. Thermal gravimetric analysis was used and it can be seen that coconut shell pyrolysis process can be divided into three stages: water loss, pyrolysis and pyrocondensation. The main components of coconut-shell oil are water (about 50 wt%), aromatic, phenolic, acid, ketone and ether containing compounds.

4.
Chem Commun (Camb) ; 51(54): 10819-22, 2015 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-26060845

RESUMO

Solutions of calcium chloride in mixed water and formamide are excellent electrolytes for capacitive charge storage in partially oxidised carbon nanotubes at unprecedented sub-zero-temperatures (e.g. 67% capacitance retention at -60 °C).

5.
Bioorg Med Chem Lett ; 24(15): 3426-9, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24953602

RESUMO

Novel bi-/tricyclic azasugars fused thiazinan-4-one were conveniently synthesized by the tandem Staudinger/aza-Wittig/cyclization reaction under microwave radiation. The aryl group (phenyl or pyridyl) in mercaptan acid had an important effect on the formation of the diastereomers of the tricyclic hybrids 12b-15b. The new bi/tricyclic azasugars 3a-8a, 4b, 6b, 8b and the known ones 2a, 2b were examined for their HIV reverse transcriptase (RT) inhibitory activities. The result showed that compounds 2a-b, 4a, 4b, 5a, and 6a could effectively inhibit RT activity. Among them, the tricyclic azasugar 5a was the best one with the IC50 value of 0.49 µM. Structure-activity relationship analysis suggested that the phenyl group in the tricyclic azasugars was benefit for their anti-HIV RT activity.


Assuntos
Compostos Aza/farmacologia , Carboidratos/farmacologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Inibidores da Transcriptase Reversa/farmacologia , Tiazinas/farmacologia , Compostos Aza/química , Carboidratos/química , Relação Dose-Resposta a Droga , Transcriptase Reversa do HIV/metabolismo , Modelos Moleculares , Estrutura Molecular , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/química , Relação Estrutura-Atividade , Tiazinas/química
6.
Soft Matter ; 10(13): 2253-63, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24652226

RESUMO

We report here a supramolecular strategy to directly assemble the small molecular antipsychotic drug chlorpromazine (CPZ) into nanostructures, induced by p-sulfonatocalix[4]arene (SC4A) and p-sulfonatocalix[4]arene tetraheptyl ether (SC4AH), with high drug loading efficiencies of 61% and 46%, respectively. The binary host-guest assembly process was monitored using optical transmittance measurements, and the size and morphology of these two kinds of supra-amphiphilic assemblies were identified using a combination of light scattering and high-resolution transmission electron microscopy, which showed solid spherical micelles. This strategy presents new opportunities for the development of high loading drug-containing carriers with easy processability for drug delivery.


Assuntos
Antipsicóticos/química , Calixarenos/química , Clorpromazina/química , Fenóis/química , Calixarenos/síntese química , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Micelas , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fenóis/síntese química , Temperatura , Água/química
7.
Bioorg Med Chem Lett ; 22(23): 7041-4, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23067552

RESUMO

Novel bicyclic iminosugar derivatives fused thiazolidin-4-one were conveniently synthesized by double Pummerer rearrangements, and their HIV reverse transcriptase (RT) inhibitory activities were preliminary examined. The notable anti-HIV-RT activity demonstrated that such bicyclic azasugars hold potential as a new kind of HIV-RT inhibitors.


Assuntos
Transcriptase Reversa do HIV/antagonistas & inibidores , Imino Açúcares/química , Inibidores da Transcriptase Reversa/síntese química , Tiazóis/química , Cristalografia por Raios X , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Humanos , Imino Açúcares/síntese química , Conformação Molecular , Ligação Proteica , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/metabolismo , Temperatura , Fatores de Tempo
8.
Bioorg Med Chem Lett ; 22(8): 2712-6, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22437112

RESUMO

A convenient synthesis of novel bi/tricyclic azasugars fused thiazolidin-4-one and thiazinan-4-one by the one-pot tandem Staudinger/aza-Wittig/cyclization reaction under microwave radiation was demonstrated. The reactions were carried out with the azidosugar 1 and mercaptan acids via a key intermediate Schiff base and stereoselectively afforded the titled bi/tricyclic azasugars in good yield. All the dominant products were in the 1,2-trans form and the reaction stereoselectivity mainly depended upon the steric hindrance of the neighboring rigid cyclic isopropylidene groups on C-2, 3 which favors the exo-attack of the sulfur atom (in mercaptan acids) to the intermediate imine. The preliminary biological evaluation of the compounds 10-17 showed that compounds 10b, 11a, 12b, 14b, 16b, 17a, and 17b were found to active the natural killer (NK) cells significantly (immunopotentiating activity) and compounds 10a, 10b, 12a, 16b, and 17b exhibited weak inhibitory activity against ß-glucosidase. Yet none of these tested compounds have obvious effects on T cell proliferation, or show inhibition against α-amylase and α-glucosidase.


Assuntos
Compostos Aza/síntese química , Compostos Aza/farmacologia , Carboidratos/síntese química , Carboidratos/farmacologia , Descoberta de Drogas , Adjuvantes Imunológicos , Compostos Aza/química , Carboidratos/química , Ciclização , Células Matadoras Naturais/citologia , Células Matadoras Naturais/efeitos dos fármacos , Micro-Ondas , Estereoisomerismo , Tiazinas/síntese química , Tiazinas/química , Tiazinas/farmacologia , Tiazolidinedionas/síntese química , Tiazolidinedionas/química , Tiazolidinedionas/farmacologia
9.
Org Biomol Chem ; 9(16): 5766-72, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21717016

RESUMO

Dinucleosides containing a thiazolidin-4-one linkage were prepared by one-pot tandem Staudinger/aza-Wittig/intermolecular cyclization under microwave irradiation and their structures were confirmed. Preliminary examination of HIV-RT inhibition showed that the dinucleosides containing (R)-thiazolidin-4-one linkage are significantly more active than those containing (S)-thiazolidin-4-one linkage.


Assuntos
Inibidores Enzimáticos/química , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/enzimologia , Nucleosídeos/química , Tiazolidinas/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/metabolismo , Micro-Ondas , Modelos Moleculares , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Tiazolidinas/síntese química , Tiazolidinas/farmacologia
10.
Bioorg Med Chem Lett ; 21(3): 916-9, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21227689

RESUMO

A series of novel ribonucleosides with C-5 OH replaced by a diaminopyrimidinyl group were synthesized by successively nucleophilic substitutions of 5'-deoxy-5'-amino-ribonucleosides with 2,4-dichloropyrimidine and then with various fatty amines under microwave irradiation. Their anticancer activities in vitro were preliminarily evaluated. Compounds 7a and 8a only exhibited anticancer activity against A549 cell line with the IC(50) values of 10.73 and 10.99 µM, respectively. In addition, 7h and 8h showed potent activities against both A549 and Hela cell lines with the IC(50) values of 12.71, 8.55 and 8.44, 5.55 µM, respectively.


Assuntos
Antineoplásicos/síntese química , Pirimidinas/química , Ribonucleosídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Micro-Ondas , Ribonucleosídeos/síntese química , Ribonucleosídeos/farmacologia
11.
Carbohydr Res ; 346(3): 401-9, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21215390

RESUMO

Novel thiazolidin-4-one-linked pseudodisaccharides 3-6 were synthesized by the one-pot tandem Staudinger/aza-Wittig/cyclization reaction at room temperature. The deacetylation of 3-6 afforded compounds 7-10, respectively. The structures of the new compounds were determined using single crystal X-ray crystallography, (1)H, (13)C, and 2D NMR spectroscopy, and HR mass spectrometry. The preliminary biological evaluation of compounds 7-10 showed that compounds 7aa, 8aa, 7ab, 8ab, 7bb and 8bb were found to have significant immunopotentiating activity. Yet none of these tested compounds have obvious inhibition against glycosidases or HIV reverse transcriptase, or show cancer cell growth inhibition.


Assuntos
Dissacarídeos/síntese química , Tiazóis/síntese química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cristalografia por Raios X , Ciclização , Dissacarídeos/química , Dissacarídeos/farmacologia , Ensaios Enzimáticos , Glucosidases/antagonistas & inibidores , Transcriptase Reversa do HIV/antagonistas & inibidores , Células HeLa , Humanos , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Estereoisomerismo , Tiazóis/química , Tiazóis/farmacologia , alfa-Amilases/antagonistas & inibidores
12.
Bioorg Med Chem Lett ; 21(1): 574-6, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21095125

RESUMO

Novel pseudonucleosides with benzylamino group on 5'-position (4) were synthesized by using the microwave-assisted one-pot tandem Staudinger/aza-Wittig/reduction reaction in good yields of 55.2-71.7%. The deacetylation of 4 afforded compounds 5. HIV-1 reverse transcriptase (RT) inhibitory and antitumor activities were preliminarily evaluated with 5. The results showed that the new pseudonucleosides (5) could effectively inhibit HIV-1 RT activity, but no antitumor activity.


Assuntos
Transcriptase Reversa do HIV/antagonistas & inibidores , Micro-Ondas , Nucleosídeos/química , Inibidores da Transcriptase Reversa/síntese química , Transcriptase Reversa do HIV/metabolismo , Humanos , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Oxirredução , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia
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