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1.
Int J Nanomedicine ; 19: 4253-4261, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766662

RESUMO

Purpose: Recently, Single-atom-loaded carbon-based material is a new environmentally friendly and stable photothermal antibacterial nanomaterial. It is still a great challenge to achieve single-atom loading on carbon materials. Materials and Methods: Herein, We doped single-atom Ag into ZIF-8-derived porous carbon to obtain Ag-doped ZIF-8-derived porous carbon(AgSA-ZDPC). The as-prepared samples were characterized by XRD, XPS, FESEM, EDX, TEM, and HAADF-STEM which confirmed that the single-atom Ag successfully doped into the porous carbon. Further, the photothermal properties and antimicrobial activity of AgSA-ZDPC have been tested. Results: The results showed that the temperature increased by 30 °C after near-infrared light irradiation(1 W/cm2) for 5 min which was better than ZIF-8-derived porous carbon(ZDPC). It also exhibits excellent photothermal stability after the laser was switched on and off 5 times. When the AgSA-ZDPC concentration was greater than 50 µg/mL and the near-infrared irradiation was performed for 5 min, the growth inhibition of S. aureus and E. coli was almost 100%. Conclusion: This work provides a simple method for the preparation of single-atom Ag-doped microporous carbon which has potential antibacterial application.


Assuntos
Antibacterianos , Carbono , Escherichia coli , Prata , Staphylococcus aureus , Antibacterianos/química , Antibacterianos/farmacologia , Prata/química , Prata/farmacologia , Porosidade , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Carbono/química , Carbono/farmacologia , Raios Infravermelhos , Testes de Sensibilidade Microbiana , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Zeolitas/química , Zeolitas/farmacologia , Imidazóis
2.
RSC Adv ; 10(29): 17123-17128, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35521468

RESUMO

A novel hypercrosslinked polymers-palladium (HCPs-Pd) catalyst was successfully prepared via the external cross-linking reactions of substituted 1,2,3-triazoles with benzene and formaldehyde dimethyl acetal. The preparation of HCPs-Pd has the advantages of low cost, mild conditions, simple procedure, easy separation and high yield. The catalyst structure and composition were characterized by N2 sorption, TGA, FT-IR, SEM, EDX, TEM, XPS and ICP-AES. The HCPs were found to possess high specific surface area, large micropore volume, chemical and thermal stability, low skeletal bone density and good dispersion for palladium chloride. The catalytic performance of HCPs-Pd was evaluated in Suzuki-Miyaura coupling reactions. The results show that HCPs-Pd is a highly active catalyst for the Suzuki-Miyaura coupling reaction in H2O/EtOH solvent with TON numbers up to 1.66 × 104. The yield of biaryls reached 99%. In this reaction, the catalyst was easily recovered and reused six times without a significant decrease in activity.

3.
RSC Adv ; 9(59): 34595-34600, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-35530001

RESUMO

Two microporous organic polymer immobilized palladium (MOP-Pd) catalysts were prepared from benzene and 1,10-phenanthroline by Scholl coupling reaction and Friedel-Crafts reaction, respectively. The structure and composition of the catalyst were characterized by FT-IR, TGA, N2 sorption, SEM, TEM, ICP-AES and XPS. MOP-Pd catalysts were found to possess high specific surface areas, large pore volume and low skeletal bone density. Moreover, the immobilized catalyst also had advantages, such as readily available raw materials, chemical and thermal stability, and low synthetic cost. The Pd catalyst is an effective heterogeneous catalyst for carbon-carbon (C-C) coupling reactions, such as the Heck reaction and Suzuki-Miyaura reaction, affording good to high yields. In these reactions, the catalyst was easily recovered and reused five times without significant activity loss.

4.
Org Lett ; 17(4): 809-11, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25636124

RESUMO

A facile and efficient one-pot synthesis of cyanoformamides was developed from readily available 1-acyl-1-carbamoyl oximes mediated by phosphoryltrichloride (POCl3) under mild conditions in good to high yields.

5.
J Org Chem ; 78(23): 11956-61, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24152217

RESUMO

A facile and efficient route for the homogeneous and highly stereoselective monohydration of substituted methylenemalononitriles to (E)-2-cyanoacrylamides catalyzed by copper(II) acetate monohydrate in acetic acid containing 2% water is described, and a mechanism is proposed. The protocol has proved to be suitable for the monohydration of dicyanobenzenes and 2-substituted malononitriles.


Assuntos
Acrilamidas/química , Cobre/química , Nitrilas/química , Compostos Organometálicos/química , Catálise , Estrutura Molecular , Estereoisomerismo
6.
Org Biomol Chem ; 11(6): 1001-6, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23288150

RESUMO

A facile and efficient synthetic route to multi-substituted 2-aminopyridines has been developed via a formal [5C + 1N] annulation of readily available 2,4-pentadienenitriles with hydroxylamine (NH(2)OH) under very mild conditions, which involves sequential intermolecular aza-nucleophilic addition of hydroxylamine, intramolecular aza-cyclization, and dehydration reactions.


Assuntos
Aminopiridinas/química , Hidroxilamina/química , Aminopiridinas/síntese química , Estrutura Molecular
7.
Org Biomol Chem ; 10(29): 5643-6, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22733188

RESUMO

A facile and efficient synthesis of substituted quinolin-2(1H)-ones is developed via intramolecular cyclization of penta-2,4-dienamides mediated by concentrated H(2)SO(4) (98%), and a mechanism involving the formation of a dicationic superelectrophile, and subsequent intramolecular nucleophilic cyclization reactions is proposed.


Assuntos
Alcadienos/química , Amidas/química , Quinolonas/química , Ácidos Sulfúricos/química , Ciclização , Quinolonas/síntese química , Estereoisomerismo
8.
Org Lett ; 14(2): 644-7, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22214189

RESUMO

A highly regioselective synthesis of 3-arylamino- and 5-arylaminoisoxazoles from enaminones based on reaction condition selection is reported. 3-Arylaminoisoxazoles were produced by treating enaminones with aqueous hydroxylamine in DMF at 100 °C, whereas 5-arylaminoisoxazoles were synthesized by subjecting enaminones to aqueous hydroxylamine in the presence of KOH and TBAB in water under reflux. A mechanism for the regioselective synthesis of 3-arylamino- and 5-arylaminoisoxazoles is proposed.


Assuntos
Isoxazóis/síntese química , Aminação , Isoxazóis/química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
9.
Chem Commun (Camb) ; (46): 6236-8, 2008 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19082131

RESUMO

A facile and efficient one-pot synthesis of substituted cyclophosphamidic chlorides and their analogues has been developed from readily available enaminones, 2-arylamino-3-acetyl-5,6-dihydro-4H-pyrans.


Assuntos
Aminas/química , Ciclofosfamida/química , Hidrogênio/química , Piranos/química , Acetilação , Metano/análogos & derivados , Metano/química , Modelos Moleculares , Estrutura Molecular
10.
Org Lett ; 10(9): 1691-4, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18380466

RESUMO

Efficient and divergent one-pot synthesis of fully substituted 1H-pyrazoles and isoxazoles from cyclopropyl oximes based on reaction conditions selection is reported. Under Vilsmeier conditions (POCl3/DMF), substituted 1 H-pyrazoles were synthesized from 1-carbamoyl, 1-oximyl cyclopropanes via sequential ring-opening, chlorovinylation, and intramolecular aza-cyclization. In the presence of POCl3/CH2Cl2, substituted isoxazoles were obtained from the cyclopropyl oximes via ring-opening and intramolecular nucleophilic vinylic substitution (SNV) reactions.


Assuntos
Isoxazóis/síntese química , Oximas/química , Pirazóis/síntese química , Isoxazóis/química , Estrutura Molecular , Pirazóis/química
11.
Org Lett ; 10(2): 345-8, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-18161982

RESUMO

A facile and efficient one-pot synthesis of polysubstituted pyridin-2(1H)-ones from a variety of beta-oxo amides under Vilsmeier conditions is described, and a mechanism involving sequential halogenation, formylation and intramolecular nucleophilic cyclization is proposed.


Assuntos
Amidas/química , Piridonas/síntese química , Catálise , Estrutura Molecular , Piridonas/química , Estereoisomerismo
12.
J Org Chem ; 72(22): 8593-6, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17915930

RESUMO

A facile and efficient one-pot synthesis of highly substituted pyridin-2(1H)-ones was developed via Vilsmeier-Haack reactions of readily available enaminones, 2-arylamino-3-acetyl-5,6-dihydro-4H-pyrans, and a mechanism involving sequential ring-opening, haloformylation, and intramolecular nucleophilic cyclization reactions is proposed.


Assuntos
Piranos/química , Piridonas/síntese química , Estrutura Molecular , Piridonas/química , Estereoisomerismo
13.
Org Lett ; 9(12): 2421-3, 2007 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-17503843

RESUMO

A facile and efficient one-pot synthesis of highly substituted pyridin-2(1H)-ones is developed via the Vilsmeier-Haack reaction of readily available 1-acetyl,1-carbamoyl cyclopropanes, and a mechanism involving sequential ring-opening, haloformylation, and intramolecular nucleophilic cyclization reactions is proposed.


Assuntos
Ciclopropanos/química , Piridonas/síntese química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Piridonas/química , Estereoisomerismo
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