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1.
Mol Divers ; 26(4): 2069-2083, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34643874

RESUMO

In this work, we synthesized new Schiff base of benzoxazine derivatives in excellent yields using multicomponent reactions of phthalaldehyde or its derivatives, primary amines, isothiocyanate, 2,4-dihydroxyacetophenone, isopropenylacetylene and methyl or ethyl amine in the presence of catalytic amount of Cu/KF/CP@MWCNTs NCs in water at room temperature. Also, the catalytic activity of the green synthesized Cu/KF/CP@MWCNTs NCs was evaluated in the reduction in organic pollutants such as 4-nitrophenol (4-NP) in water at mild conditions. The results indicated that the biosynthesized NCs have very high and effective catalytic activity for organic pollutants within few seconds. As well the antioxidant activity of some synthesized benzoxazine was studied using trapping of radical by DPPH and ferric reduction activity potential (FRAP) experiment. The short time of reaction, high yields of product, easy separation of catalyst and products are some benefits of this procedure.


Assuntos
Poluentes Ambientais , Nanocompostos , Benzoxazinas , Catálise , Bases de Schiff , Água , Zeolitas
2.
Comb Chem High Throughput Screen ; 24(1): 119-128, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32504497

RESUMO

Aims & Objective: An efficient procedure for the synthesis of pyrido[2,1-a]isoquinoline derivatives in excellent yields was investigated using catalyst-free multicomponent reaction of phthaladehyde, methylamine, activated acetylenic compounds, alkyl bromides and triphenylphosphine in water under ultrasonic irradiation at room temperature. In addition, Diels- Alder reactions of pyrido[2,1-a]isoquinoline derivatives with activated acetylenic compounds under ultrasonic irradiation are investigated in two procedures. The advantages of this procedure compared to report methods are short time of reaction, high yields of product, easy separation of product, clean mixture of reaction and green media for performing reaction. In addition, because of having isoquinoline core in synthesized compounds, in this research antioxidant activity of some synthesized compounds was studied. MATERIALS AND METHODS: To a stirred mixture of phthalaldehyde 1 (2 mmol) and methylamine 2 (2 mmol) in water (3 mL) under ultrasonic irradiation was added to activated acetylenic compounds 4 after 20 min. Alkyl bromide 3 and triphenylphosphine 5 react in another pot in water (3 mL) under ultrasonic irradiation for 15 min. After this time, this mixture was added to the first pot. After completion of the reaction, the solid residue was separated by filtration and washed with Et2O to afforded pure title compound 6. RESULTS: In this work, generation of pyrido[2,1-a]isoquinoline derivatives 6 are performed using phthalaldehyde 1, methylamine 2, α-halo substituted carbonyls 3, activated acetylenic compounds 4 and triphenylphosphine 5 in water under ultrasonic irradiation condition at room temperature in excellent yield at short time. CONCLUSION: In summary, multicomponent reaction of phthaladehyde, methylamine, activated acetylenic compounds, alkyl bromides and triphenylphosphine in water under ultrasonic irradiation at room temperature produced pyrido[2,1-a]isoquinoline derivatives in excellent yields. Also, Diels-Alder reaction of pyrido[2,1-a]isoquinoline derivatives with activated acetylenic compounds and triphenylphosphine under ultrasonic irradiation is investigated in two procedures. Also, the antioxidant activities of 6a, 6c, 6g and 6i were evaluated by DPPH radical scavenging and ferric reducing power analyzes. The compounds 6a exhibit excellent DPPH radical scavenging activity and FRAP compared to synthetic antioxidants BHT and TBHQ. The chief benefits of our method are high atom economy, green reaction conditions, higher yield, shorter reaction times, and easy work-up, which agree with some principles of green chemistry.


Assuntos
Antioxidantes/síntese química , Isoquinolinas/síntese química , Aldeídos/química , Alcinos/química , Antioxidantes/farmacologia , Brometos/química , Catálise , Compostos Férricos/química , Sequestradores de Radicais Livres/química , Química Verde , Humanos , Isoquinolinas/farmacologia , Metilaminas/química , Compostos Organofosforados/química , Oxirredução , Ultrassom
3.
Curr Org Synth ; 17(1): 40-45, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103716

RESUMO

AIMS AND OBJECTIVES: A one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives by threecomponent cyclo-condensation of isatoic anhydride, aldehydes and amine or ammonium acetate has been developed using 3,5-Bis(trifluoromethyl) phenylammonium triflate (BFPAT) as a new organocatalyst. MATERIALS AND METHODS: All of the obtained products are known compounds and identified by IR, 1HNMR, 13CNMR and melting points. RESULTS: A wide variety of structurally different aldehydes reacted easily and rapidly to result in the relating 2,3-dihydroquinazolin-4(1H)-ones in good to excellent yield. CONCLUSION: We have demonstrated an extremely effective and new process for synthesizing 2,3- dihydroquinazolin-4(1H)-ones employing BFPAT as a novel organocatalyst in one-pot fashion.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31914908

RESUMO

AIMS AND OBJECTIVE: Ionic liquids are a suitable medium for stabilization and preparation of catalytic systems. MATERIALS AND METHODS: The two-dimensional (2D) ZnO/Fe3O4 nanocomposites were synthesized using ionic liquid [OMIM]Br as a stabilizer and soft template. The nanocomposites were characterized via FTIR, XRD, VSM and SEM analysis. RESULT: The catalytic activity of these composites was evaluated using a multicomponent reaction of primary amines, acetylacetone, and 2-bromoacetophenone. CONCLUSION: 2D ZnO/Fe3O4 as a recyclable and green catalyst showed excellent catalytic performance for the preparation of poly-substituted pyrroles.


Assuntos
Líquidos Iônicos/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Pirróis/síntese química , Óxido de Zinco/química , Catálise , Líquidos Iônicos/síntese química , Estrutura Molecular , Pirróis/química
5.
Comb Chem High Throughput Screen ; 20(9): 781-786, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28982323

RESUMO

OBJECTIVE: Functionalized benzenes are prepared from the reaction of sulfonoketenimides that is produced from the Copper catalyzed reaction of terminal alkynes and sulfonyl azides with zwitterionic intermediate that is generated from the reaction of dialkyl acetylenedicarboxylates, alkyl bromides and triphenylphosphine in the presence of ZnO-nanoparticles in good yields. MATERIAL AND METHODS: All chemicals employed in this work were prepared from Fluka (Buchs, Switzerland) and were used without further purification. Nanoparticles of ZnO were synthesized according to literature report. Melting points were measured on an Electrothermal 9100 apparatus. Elemental analyses for C, H, and N were performed using a Heraeus CHN­O-Rapid analyzer. Mass spectra were recorded on a FINNIGAN-MAT 8430 spectrometer operating at an ionization potential of 70 eV. IR spectra were measured on a Shimadzu IR-460 spectrometer. 1H, and 13C NMR spectra were measured with a BRUKER DRX-500 AVANCE spectrometer at 500.1 and 125.8 MHz, respectively. RESULTS: In these reactions, the first step is optimization of reaction conditions for achieving best conditions. For this reason, solvent, catalyst, and reaction time is changed so that the best result is obtained. For optimization, several catalysts such as CuI, CuBr, CuCl, ZnO-nanoparticles, CM-ZnO, pyridine, piperidine, CuO-NPs, TiO2-NPs and copper powder were checked. Among them CuI and ZnO-NPs give the best results. Also, several solvents such as CH3CN, H2O, solvent-free conditions, toluene and diethyl ether are employed and CH3CN is the best solvent. CONCLUSION: In summary, sulfonoketenimides react with intermediate that is generated from the reaction of dialkyl acetylenedicarboxylate, alkyl bromides and triphenylphosphine in the presence of ZnO-NPs (10 mol%) to produce benzene derivatives in good yields.


Assuntos
Amidas/química , Derivados de Benzeno/síntese química , Nanopartículas/química , Óxido de Zinco/química , Derivados de Benzeno/química , Catálise , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
6.
Comb Chem High Throughput Screen ; 20(4): 304-309, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28294057

RESUMO

Aims & Scope: Thiazole derivatives are produced using one-pot multicomponent reactions of acid chlorides, potassium thiocyanate, amino acids, alkyl bromides and ZnO nanorods (NR-ZnO) as the catalyst in water at ambient temperature. These reactions were no't performed without using NR-ZnO as the catalyst. Nanorods of ZnO have been prepared by reflux procedure using sodium dodecylsulfate (SDS). Nanorods of ZnO showed a considerable improvement in the yield of the product and displayed significant reusable activity. MATERIALS AND METHODS: In these reactions, all chemicals were prepared from Fluka (Buchs, Switzerland). Nanorods of ZnO were synthesized in the laboratory according to literature report. By using an electrothermal 9100 apparatus, melting points of synthesized compounds were determined. Heraeus CHN-O-Rapid analyzer was employed for elemental analyses for C, H, and N. FINNIGANMAT 8430 spectrometer operating at an ionization potential of 70 eV was used for mass spectra. Shimadzu IR-460 spectrometer was employed for IR spectra. BRUKER DRX-500 AVANCE spectrometer at 500.1 and 125.8 MHz was used for 1H, and 13C NMR spectra for solutions in CDCl3 with TMS as internal standard or 85% H3PO4 as external standard, respectively. RESULTS: We describe a facile and green synthetic method for the synthesis of thiazole derivatives 5 from acid chlorides, potassium thiocyanate, alkyl bromides and amino acids using NR-ZnO- as the catalyst in water at room temperature. CONCLUSION: In conclusion, we describe an efficient, green procedure and high yielding synthesis of thiazole derivatives using acid chlorides, potassium thiocyanate, alkyl bromides and amino acids in the presence of NR-ZnO as the catalyst in water at room temperature.


Assuntos
Nanotubos/química , Tiazóis/síntese química , Óxido de Zinco/química , Catálise , Química Verde/métodos , Nanotubos/ultraestrutura , Tiazóis/química , Tiocianatos/química , Água/química
7.
Comb Chem High Throughput Screen ; 18(9): 872-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26004051

RESUMO

Three- component reactions of 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone, aldehydes and malononitrile or ethyl cyanoacetate in the presence of nanoparticles of ZnO as catalyst are explained as effective and green synthetic method for generating 9H- furo[2,3-f]chromenes in good yield.


Assuntos
Benzopiranos/síntese química , Nanopartículas/química , Óxido de Zinco/síntese química , Estrutura Molecular , Relação Estrutura-Atividade , Óxido de Zinco/química
8.
Comb Chem High Throughput Screen ; 18(5): 505-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25924658

RESUMO

This study was focused on evaluation of the cytotoxicity and apoptotic affects of benzofuran derivative on MCF-7 breast cancer cell line. This effective compound was isolated from the root of Petasites hybridus plant. For experiments, the MCF-7 cells were treated with several concentrations (0-500µM) of 1-(6-hydroxy-2- isopropenyl-1-benzofuran-5-yl)-1-ethanone 1 at different times. In this study, test of neutral red was also employed for cytotoxicity assay and quantity of P53, P21. Bax genes expression was analyzed using Real-Time PCR and ELISA techniques. Results show that compound 1 has cytotoxicity and apoptotic effects on Human breast cancer (Michigan Cancer Foundation-7) MCF-7 cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Benzofuranos/farmacologia , Produtos Biológicos/farmacologia , Neoplasias da Mama/patologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Benzofuranos/química , Benzofuranos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Estrutura Molecular , Petasites/química , Raízes de Plantas/química , Relação Estrutura-Atividade
9.
Artigo em Inglês | MEDLINE | ID: mdl-25373506

RESUMO

An effective one-pot synthesis of dialkoxyphosphoryl-2-oxo-2H-pyran derivatives by three-component reaction of alky bromides and dialkyl acetylenedicarboxylates in the presence of trialkyl phosphite is described. The reactions were performed under solvent-free conditions at 50°C and neutral conditions and provided good yields of products.


Assuntos
Acetileno/química , Ácidos Dicarboxílicos/química , Química Verde , Hidrocarbonetos Bromados/química , Organofosfonatos/síntese química , Fosfitos/química , Pironas/síntese química , Acetileno/análogos & derivados , Estrutura Molecular , Organofosfonatos/química , Pironas/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-25262751

RESUMO

Studies on the interactions between metallodrugs and human serum albumin (HSA), as carrier for drugs and biological molecules, are extremely important to design and discover new drugs. The interaction of three novel synthesized complexes of [Pd(phen)(R-gly)]NO3, where R-gly is methyl-, propyl-, and amyl-glycine and phen is 1,10- phenanthroline, with HSA were investigated using spectroscopic studies in combination with a molecular dynamic simulation. These water soluble complexes can denature HSA at ~50 µM. According to the results obtained for the isothermal titration at 27 and 37°C, it was found that there are 10, 8, and 6 binding sites (g) for methyl-, propyl-, and amyl-glycine complexes on the HSA with positive cooperativity in binding, respectively. Also, the binding and thermodynamic parameters were analyzed. We found a good consistency between secondary structure and simulation data with spectroscopic studies, and the experimental data are confirmed by molecular simulation results. In addition, the results related to helix, beta sheets, and coil percentages revealed that all complexes decrease the helix structure and increase the beta structure; and that the amyl derivative is more effective in denaturing the HSA structure.


Assuntos
Simulação de Dinâmica Molecular , Compostos Organometálicos/química , Paládio/química , Albumina Sérica/química , Humanos , Estrutura Molecular , Compostos Organometálicos/síntese química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
11.
Comb Chem High Throughput Screen ; 17(1): 35-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23755720

RESUMO

An efficient synthesis of 1,3-oxathiolan-2-yliden derivatives is described via a simple reactions between CHacids, CS2 and oxiranes in the presence of triethylamine at 70° C in water as the solvent. The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of this method.


Assuntos
Compostos de Epóxi/química , Tiofenos/síntese química , Água/química , Dissulfeto de Carbono/química , Etilaminas/química , Química Verde , Espectroscopia de Ressonância Magnética , Nitrilas/química , Pentanonas/química , Temperatura
12.
Comb Chem High Throughput Screen ; 16(10): 788-90, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23848311

RESUMO

A water-accelerated multicomponent synthesis of organic target molecules has been used as a key method for the preparation of novel imidazole derivatives. The three-component condensation reactions of primary amines with trichloroacetonitrile in the presence of ninhydrine in water are developed as efficient and clean green synthetic procedures for the high-yielding preparation of imidazoles.


Assuntos
Imidazóis/síntese química , Água/química , Imidazóis/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
13.
Comb Chem High Throughput Screen ; 16(10): 840-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23782038

RESUMO

A simple and proficient method for the synthesis of 1,3-benzoxazine derivatives via three-component reaction of isocyanide and isoquinoline with 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone or 4-hydroxycumarine in water in the presence of piperidine at 70°C is reported.


Assuntos
Benzoxazinas/síntese química , Água/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho
14.
Comb Chem High Throughput Screen ; 16(9): 758-61, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23721069

RESUMO

An efficient synthesis of thiazoles is described via an one-pot reaction between acid chlorides, ammonium thiocyanate tetramethylguanidine and α-bromocarbonyl compounds under solvent-free conditions without using any catalyst. The method offers several advantages including high yields of products and an easy work-up procedure at room temperature in excellent yield.


Assuntos
Isotiocianatos/química , Tiazóis/síntese química , Cloretos/química , Guanidinas/química , Tiazóis/química
15.
Comb Chem High Throughput Screen ; 16(8): 652-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23713458

RESUMO

An efficient synthesis of functionalized tetrahydroimidazoles via a one-pot tandem reaction between ninhydrin, primary alkylamines, arylisocyanates or arylisothiocyanates, acetylenic esters and triphenylphosphine is described.


Assuntos
Imidazóis/síntese química , Aminas/química , Imidazóis/química , Isocianatos/química , Ninidrina/química , Compostos Organofosforados/química
16.
Comb Chem High Throughput Screen ; 16(1): 73-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23190556

RESUMO

Adsorption of phenolic compounds and chemical analysis of them from a local production cigarette (named by Farvardin cigarette) smoke have been investigated by using perlite filtration. In this research, the mainstream smoke was tested by three filtration methods: Perlite filter, Cambridge filter and general cigarette filter. Then the used filter was extracted by pure methanol as solvent. After that, the extracted solution was analysed by GC-MS. By this consideration, the phenolic derivatives such as phenol, hydroquinone, resorcinol, pyrocatechol, m-cresol, p-cresol and o-cresol were detected. The structure of the perlite filtration after absorption was studied by SEM. In addition, its chemical structure was investigated by XRD and XRF.


Assuntos
Óxido de Alumínio/química , Filtração/instrumentação , Fenóis/isolamento & purificação , Dióxido de Silício/química , Poluição por Fumaça de Tabaco/análise , Cromatografia Gasosa-Espectrometria de Massas
17.
Comb Chem High Throughput Screen ; 15(10): 822-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23140191

RESUMO

A series of thiophene derivatives were synthesized via one-pot multicomponent reactions of alkyl bromides, aroyl or alkanoyl isothiocyanates, 1,3-dicarbonyl compounds and secondary amines under microwave irradiation at 80°C. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and straightforward procedure.


Assuntos
Hidrocarbonetos Bromados/química , Micro-Ondas , Tiofenos/síntese química , Técnicas de Química Combinatória , Estrutura Molecular , Tiofenos/química
18.
Comb Chem High Throughput Screen ; 15(10): 835-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23140192

RESUMO

Multicomponent reactions involving 4-hydroxycumarine, activated acetylenic compounds and N-nucleophiles under solvent-free conditions were investigated. The reactions could also be extended to quinoline or CH-acides. Substituted chromen could be obtained from this routine, which may have potential applications in drugs fields.


Assuntos
Benzopiranos/síntese química , 4-Hidroxicumarinas/química , Acetileno/análogos & derivados , Acetileno/química , Benzopiranos/química , Técnicas de Química Combinatória , Estrutura Molecular , Solventes
19.
Comb Chem High Throughput Screen ; 15(10): 816-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23092197

RESUMO

Stable derivatives of oxaphosphaphenanthrenes were prepared by using the reactions of dialkyl acetylenedicarboxylate with 3-bromo-2-naphthol in the presence of trimethyl or triphenyl phosphite under microwave conditions at 70°C in good yields. Under similar conditions, chromene derivatives were produced by using triethyl phosphite and dialkyl acetylenedicarboxylate in the presence of OH-acids in excellent yields.


Assuntos
Benzopiranos/síntese química , Micro-Ondas , Fenantrenos/síntese química , Fosfitos/química , Benzopiranos/química , Técnicas de Química Combinatória , Estrutura Molecular , Fenantrenos/química
20.
Comb Chem High Throughput Screen ; 15(4): 354-7, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22263857

RESUMO

A one-pot synthesis of cyclopentanone derivatives from phosphorus ylide under lab-type microwave assisted methodology was described. The phosphorus ylides were obtained via the reaction of activated acetylenic compounds, ethyl 4-chloroacetoacetate and triphenylphosphine. The structure of phosphorus ylides was assigned by ¹H, ¹³C and ³¹PNMR. The phosphorus ylides as precursor were crystallized as two enantiomers (R,R) and (S,S) and one of the phosphorus ylide structures was confirmed by single X-ray crystallography.


Assuntos
Técnicas de Química Combinatória/métodos , Ciclopentanos/síntese química , Compostos Organofosforados/química , Acetoacetatos/química , Cristalografia por Raios X , Ciclopentanos/química , Micro-Ondas , Modelos Moleculares
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