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1.
Bioorg Chem ; 141: 106804, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37806049

RESUMO

In this study, we bring forward a green and novel eco-friendly strategy for the fabrication of Ag/g-C3N4 nanocomposite via a fast in-situ generation method using Ferula Gummosa extracts as both stabilizer and reducing agent. Ag/g-C3N4 nanocomposite was analyzed by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX-MAP), and transmission electron microscopy (TEM). After procurement and characterization, the catalytic activity of the prepared reagent was surveyed in the synthesis of a new series of depsipeptides using aspirin/ketoprofen, cyclohexyl isocyanide, and aryl aldehydes at ambient temperature in EtOH/H2O as a green media. Taking into account the economic and environmental facets, the method bestows some advantages such as using plant extracts as green media for the preparation of Ag nanoparticles, simple work-up procedure, mild reaction conditions, short reaction times, and high yields of the products. Additionally, the Ag/g-C3N4 nanocomposite catalyst can be recycled effectually and reused several times without a substantial loss in reactivity.


Assuntos
Depsipeptídeos , Nanopartículas Metálicas , Nanocompostos , Neoplasias , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Prata/química , Nanocompostos/química
2.
J Mol Struct ; 1226: 129336, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33012844

RESUMO

In this project, a recently synthesized DABCO-based catalyst is entrapped in agar to reduce its moisture sensitivity leading to enhancement of its stability and catalytic activity. After preparation and identification this new reagent is used as an efficient and environmentally safe catalyst for the preparation of 1, 2, 4-triazoloquinazolinone and some pyrimidine derivatives. This method is accompanied with some superiorities such as, simple operation, mild and green conditions, use of low cost and non-hazardous natural material, short reaction times, easy preparation methods and simple work-up procedures. The prepared catalyst can be re-used for several times in all of the studied reactions without any appreciable loss in its activity.

3.
J Nanosci Nanotechnol ; 19(7): 3859-3870, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30764944

RESUMO

Fe3O4@MCM-41@Zirconium magnetic nanoparticles modified with piperazine (Fe3O4@MCM-41@Zr-piperazine), as a newly reported catalyst, shows excellent catalytic activity in N-Tert-butoxycarbonylation of amines under the mild and solvent-free conditions. Accordingly, different derivatives of N-Tert-butylcarbamates owning diverse aliphatic, aromatic and heteroaromatic amines were prepared efficiently. Good performance of this method for the majority of used complex or acid-sensitive substrates and facile separation of this nanocatalyst due to its superparamagnetic nature from the reaction mixture via an external magnetic field for several times are the most important striking features of this protocol.

4.
J Nanosci Nanotechnol ; 19(6): 3447-3458, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30744772

RESUMO

Immobilized NaHSO4 on core/shell phenylene bridged periodic mesoporous organosilica magnetic nanoparticles (Fe3O4@Ph-PMO-NaHSO4) as a new acidic magnetically separable nanocatalyst was successfully prepared in three steps: (i) preparation of Fe3O4 nanoparticles by a precipitation method, (ii) synthesis of an organic-inorganic periodic mesoporous organosilica structure with phenyl groups on the surface of Fe3O4 magnetic nanoparticles (MNPs) and (iii) finally adsorption of NaHSO4 on periodic mesoporous organosilica (PMO) network. The prepared organic-inorganic magnetic reagent was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption-desorption and energy-dispersive X-ray (EDX) techniques. Finally, it was used as a reusable and new catalyst to promote the synthesis of tetrahydrobenzo[b]pyran and pyrano[2,3-d]pyrimidinone derivatives as important biologically active compounds. Eco-friendly protocol, high yields, short reaction times and easy and quick isolation of the products are the main advantages of this procedure.

5.
J Nanosci Nanotechnol ; 19(4): 2099-2107, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486952

RESUMO

Nanoporous Na+-montmorillonite perchloric acid as a novel heterogeneous reusable solid acid catalyst was easily prepared by treatment of Na+-montmorillonite as a cheap and commercially available support with perchloric acid. The catalyst was characterized using a variety of techniques including X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), energy dispersive X-ray spectroscopy (EDX), pH analysis and determination of the Hammett acidity function. The prepared reagent showed excellent catalytic activity for the chemoselective conversion of alcohols and phenols to their corresponding trimethylsilyl ethers with 1,1,1,3,3,3-hexamethyldisilazane (HMDS) at room temperature. Deprotection of the resulting trimethylsilyl ethers can also be carried out using the same catalyst in ethanol. All reactions were performed under mild and completely heterogeneous reaction conditions in good to excellent yields. The notable advantages of this protocol are: short reaction times, high yields, availability and low cost of the reagent, easy work-up procedure and the reusability of the catalyst during a simple filtration.

6.
J Nanosci Nanotechnol ; 19(8): 4503-4511, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913741

RESUMO

Butane-1-soltunic acid modified starch-coated γ-Fe2O3 magnetic nanoparticles [γ-Fe2O3@starch-n-butyl SO3H] was easily prepared through a ring opening reaction of 1, 4-butane sultone with nano-magnetic γ-Fe2O3@starch. After structural studies, using FT-IR, SEM, XRD, TGA, TEM, EDX, VSM and also pH analysis the efficiency of this reagent in the preparation of tetrahydrobenzimidazo[2,1-b] quinazolin-1(2H)-ones and 2H-indazolo[2,1-b]phthalazine-triones was studied. Operational simpleness, high yields, short reaction times, wide applicability and simple recyclability of the catalyst employing an external magnet are the most important advantages of this methodology.

7.
Bioorg Chem ; 77: 68-73, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29334621

RESUMO

Taurine, a ß-amino acid that is abundantly available in the tissues of human and animals, is efficiently used as a green bio-organic catalyst in the preparation of some of the biologically active barbituric and thiobarbituric acid derivatives. In the presence of taurine, 5-Arylidene (thio) barbituric acid derivatives were prepared via Knovenagel reaction between aldehydes and (thio)barbituric acid. Using this reagent also pyrano[2,3-d]pyrimidinone(thione) derivatives were synthesized through a three-component reaction between aldehydes, (thio)barbituric and malononitrile. Both reactions are performed in water with good to excellent yields during acceptable reaction times. No organic solvent was used during reaction or separation steps and no extra-purification was exerted. Meanwhile, reusability of taurine was easy and noticeably high.


Assuntos
Barbitúricos/síntese química , Taurina/química , Tiobarbitúricos/síntese química , Água/química , Barbitúricos/química , Catálise , Estrutura Molecular , Tiobarbitúricos/química
8.
Bioorg Chem ; 81: 326-333, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30179795

RESUMO

An improved, forthright, and highly efficient one-pot synthesis of a wide range of pharmaceutically exciting diverse kind of functionalized 2-amino-3-cyano-4H-pyrans and especially bis-pyrans compounds is developed using piperazine as a low-cost and environmentally benign commercially available basic catalyst in aqueous media. The attractive features of this process are simple procedure, short reaction times, high yields, no column chromatographic separation and commercial availability and recyclability of the catalyst. Also, piperazine can catalyze the synthesis of the target compounds on a larger scale. Furthermore, rational mechanism was suggested via GC-Mass analysis of the trapped intermediates.


Assuntos
Nitrilas/síntese química , Piperazina/química , Piranos/síntese química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Catálise , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Química Verde/métodos , Modelos Químicos , Nitrilas/farmacologia , Piranos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Água/química
9.
J Nanosci Nanotechnol ; 18(2): 1194-1198, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448556

RESUMO

In this work, an efficient and green procedure have been described for the synthesis of tetrahydrobenzimidazo[2,1-b]quinazolin-1(2H)-one derivatives using nanoporous sodium montmorillonite clay (Na+-MMT) modified with 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate (Na+-MMT-[pmim]HSO4). The procedure gave the products in excellent yields in very short reaction times under solvent-free condition. Also this catalyst can be reused for six times without considerable loss of its catalytic activity.

10.
J Nanosci Nanotechnol ; 18(1): 591-603, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29768885

RESUMO

In this research work, 4,4'-(butane-1,4-diyl)bis(1-sulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium) tetrachloride (NS-C4(DABCO-SO3H)2 · 4Cl) as a new nano-sized N-sulfonic acid was prepared and characterized using different types of spectroscopic methods including FT-IR, 1H NMR, 13C NMR, XRD, TGA and SEM analysis. This new reagent was efficiently used as catalyst for the promotion of the one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-1,6,11(13H)-triones derivatives, as a class of biologically active compounds with important pharmaceutical properties, under solvent-free conditions during short reaction times in high yields.

11.
RSC Adv ; 14(13): 9218-9227, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38505388

RESUMO

In this work, a comparison between the catalytic activity of two piperazine based ionic liquids immobilized on ZnO NPs and SiO2 NPs is presented in the synthesis of benzoxazoles and benzimidazoles. These reactions are performed under solvent free conditions during appropriate reaction times with high yields. The catalyst obtained from ZnO-NPs (PINZS), as the more efficient one, is used for the efficient promotion of the N-Boc protection of amines. High chemoselectivity, no by-products, facile separation of the catalyst, short reaction times and no need for volatile organic solvents are the best features of the proposed methods.

12.
RSC Adv ; 14(19): 13452-13462, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38665495

RESUMO

In this research and in the line of our researches on the use of nano-substrates modified with ionic liquid in organic reactions, an efficient and green method for the one-pot three-component synthesis of pyrimido[1,2-a]benzimidazole and 1-(benzothiazolylamino)methyl-2-naphthol derivatives is reported using a new nanoporous catalyst formulated as ZnO@SO3H@Tropine. Further analysis of the catalyst for its characterization has been performed using thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Fourier-transform infrared spectroscopy (FT-IR). The present approach creates a variety of biologically active heterocyclic compounds with excellent yields and short reaction times. Among the other advantages of the current method are: ease of operation, clean reaction profiles and ease of separation. Also, this catalyst can be reused five times without loss of its catalytic activity.

13.
Acta Chim Slov ; 60(4): 889-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24362994

RESUMO

Pyrido[2,3-d]pyrimidine derivatives were synthesized regioselectivly in good to high yields by one-pot three-component condensation of 6-amino-2-(methylthio)pyrimidin-4(3H)-one, aromatic aldehydes and ethylcyanoacetate or meldrum's acid using 1,2-dimethyl-N-butanesulfonic acid imidazolium hydrogen sulfate ([DMBSI]HSO4) Brønsted-acidic ionic liquid as catalyst. Solvent-free mild reaction conditions, short reaction times, easy work-up, and reusability of the catalyst are the main advantages of this protocol.


Assuntos
Ácidos/química , Líquidos Iônicos/química , Pirimidinas/síntese química , Catálise , Estrutura Molecular
14.
RSC Adv ; 13(50): 35659-35671, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38077967

RESUMO

In this study, [DABCO](SO3H)2CuCl4 as a novel DABCO-based molten salt with dual acidic functionality (Brønsted and Lewis) has been synthesized, characterized and used as a high-performance catalyst in the one-pot synthesis of 3,4-dihydropyrimidine and polyhydroquinoline derivatives. The identification of this catalyst was accomplished by using techniques such as infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDS) spectroscopy. Excellent efficiency, short reaction times, a simple working method and also use of a recyclable catalyst are the considerable advantages of this process.

15.
RSC Adv ; 13(45): 31470-31479, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37901261

RESUMO

In this study, a novel natural deep eutectic solvent was prepared from glucose, pregabalin, and urea. The prepared solvent was identified using a variety of techniques, including Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and refractive index measurements (RI). The prepared deep eutectic solvent was then utilized for the one-pot synthesis of quinazolinone derivatives. The yields of the product obtained with and without the catalyst were determined, providing insights into the catalytic efficiency of the system. This protocol offers several advantages, including mild reaction conditions, easy reagent preparation, a green process, short reaction times (2-60 min), high yields (80-99%), and a straightforward procedure with the possibility of catalyst reusability.

16.
Colloids Surf B Biointerfaces ; 225: 113282, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37003247

RESUMO

Human bones can suffer from various injuries, such as fractures, bone cancer, among others, which has initiated research activities towards bone replacement using advanced bio-materials. However, it is still challenging to design bio-scaffolds with bone-inducing agents to regenerate bone defects. In this regard, MAX-phases and MXenes (early transition metal carbides and/or nitrides) have gained notable attention due to their unique hydrophilicity, bio-compatibility, chemical stability, and photothermal properties. They can be used in bone tissue engineering as a suitable replacement or reinforcement for common bio-materials (polymers, bio-glasses, metals, or hydroxyapatite). To fabricate bio-scaffolds, additive manufacturing is prospective due to the possibility of controlling porosity and creating complex shapes with high resolution. Until now, no comprehensive article summarizing the existing state-of-the-art related to bone scaffolds reinforced by MAX-phases and MXenes fabricated by additive manufacturing has been published. Therefore, our article addresses the reasons for using bone scaffolds and the importance of choosing the most suitable material. We critically discuss the recent developments in bone tissue engineering and regenerative medicine using MAX-phases and MXenes with a particular emphasis on manufacturing, mechanical properties, and bio-compatibility. Finally, we discuss the existing challenges and bottlenecks of bio-scaffolds reinforced by MAX-phases and MXenes before deriving their future potential.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Humanos , Alicerces Teciduais/química , Estudos Prospectivos , Regeneração Óssea
17.
Bioorg Med Chem Lett ; 22(18): 5956-60, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22892120

RESUMO

Novel fused 1H-benzo[f]chromen-indole derivatives were synthesized regioselectivly in good to high yields by triethyl amine catalyzed condensation of 3-cyanoacetylindoles, ß-naphthol and aryl aldehydes in methanol under ultrasounic irradiations and conventional conditions. The easy work-up of the products, rapidity, and mild reaction conditions are notable features of this protocol. The antibacterial activity of the selected products was examined. Some products showed promising activities.


Assuntos
Antibacterianos/farmacologia , Benzopiranos/síntese química , Indóis/química , Antibacterianos/síntese química , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Benzopiranos/química , Benzopiranos/farmacologia , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella enterica/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
18.
Water Environ Res ; 94(3): e10695, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35243716

RESUMO

The efficiency of removing chemical oxygen demand (COD) and turbidity from wood wastewater was investigated using a sequencing batch reactor (SBR) and the photo-Fenton process. A total of 94.78% of COD reduction and 99.9% of turbidity removal were observed under optimum conditions of SBR, which consisted of an organic loading rate (OLR) of 0.453 kg COD m-3  day-1 , mixed liquor suspended solids (MLSS) of 4564 mg L-1 , and cycle time of 48 h. A magnetic α-Fe2 O3 @TiO2 @SO3 H nanocatalyst was prepared as a heterogeneous Fenton reagent. The Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and elemental mapping (MAP) analyses were performed to determine the structure and morphology of synthesized photocatalyst. The response surface methodology (RSM) was used to optimize the process based on a central composite design (CCD). The maximum photocatalytic degradation of 87.54% and COD reduction of 83.35% were achieved at a dosage of 0.6 g L-1 of catalyst, 30 mg L-1 of H2 O2 , and pH of 3.5 for 45 min. The results indicated that a combination of the SBR process and α-Fe2 O3 @TiO2 @SO3 H could be used as an effective method for the treatment of wood wastewater. PRACTITIONER POINTS: A combination of the SBR and photo-Fenton process was introduced as an impressive method for wood industry wastewater treatment. The efficiencies of COD, BOD5 , NO3 -N, PO4 -P, and color removal were obtained according to the standard limits in Iran. To our knowledge, this study is the first report of the use of synthesized α-Fe2 O3 @TiO2 @SO3 H photocatalyst for the wood industry wastewater treatment.


Assuntos
Águas Residuárias , Madeira , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio , Águas Residuárias/química
19.
Int J Biol Macromol ; 219: 709-720, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-35961551

RESUMO

In this project, different photosensitizers were prepared using different ratios of nickel, manganese, and iron. Then, multiple analysis were performed to evaluate their efficiency, and the most suitable one was used to be coated by hyaluronic acid to improve the nano-platform's biocompatibility and target ability. Moreover, another chemical targeting agent (riboflavin) was used to further improve the target ability of the prepared nano-platform. Different spectroscopies and thermal analysis were used to determine the physical and chemical characteristics of the prepared nano-platform. Also, in order to determine the biocompatibility of the nano-platform, in vitro and in vivo tests such as blood hemolysis, blood aggregation and lethal dose were performed. Then, an anti-cancer agent (curcumin) was loaded on the selected nano-platform to makes us able utilizing the synergistic effect of chemotherapy and photodynamic therapy simultaneously. Finally, the cell cytotoxicity results showed that the prepared nano-platform had a great anti-cancer potential which can make it a great candidate as a dual photo and chemo therapy agent for treatment of breast cancers.


Assuntos
Curcumina , Nanopartículas , Neoplasias , Fotoquimioterapia , Óxido de Alumínio , Linhagem Celular Tumoral , Doxorrubicina/química , Compostos Férricos , Humanos , Ácido Hialurônico/química , Ferro , Óxido de Magnésio , Manganês , Nanopartículas/química , Níquel , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Riboflavina
20.
Pharmaceutics ; 14(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35214054

RESUMO

This review provides a summary of recent progress in the development of different nano-platforms for the efficient synergistic effect between photodynamic therapy and chemotherapy. In particular, this review focuses on various methods in which photosensitizers and chemotherapeutic agents are co-delivered to the targeted tumor site. In many cases, the photosensitizers act as drug carriers, but this review, also covers different types of appropriate nanocarriers that aid in the delivery of photosensitizers to the tumor site. These nanocarriers include transition metal, silica and graphene-based materials, liposomes, dendrimers, polymers, metal-organic frameworks, nano emulsions, and biologically derived nanocarriers. Many studies have demonstrated various benefits from using these nanocarriers including enhanced water solubility, stability, longer circulation times, and higher accumulation of therapeutic agents/photosensitizers at tumor sites. This review also describes novel approaches from different research groups that utilize various targeting strategies to increase treatment efficacy through simultaneous photodynamic therapy and chemotherapy.

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