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1.
Mol Divers ; 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403738

RESUMO

The synthesis of novel, high-yield derivatives of chromenoazepine was investigated in this work. CuO/TiO2@MWCNTs was used as a nanocatalyst in a multicomponent reaction involving 4-aminocumarine, activated acetylenic chemicals, and alkyl bromide in room temperature water to create these novel compounds. Using MCRs of 4-aminocumarine, isothiocyanate, and alkyl bromide in the presence of CuO/TiO2@MWCNTs as nanocatalysts in room-temperature water, chromenothiazepines were synthesized under comparable conditions. The freshly synthesized azepine exhibits antioxidant activity since its NH group has undergone two evaluation processes. Additionally, using two types of Gram-negative bacteria in a disk distribution procedure, the antibacterial activity of recently developed azepines was evaluated, and these compounds also inhibited the growth of Gram-positive bacteria. This method's benefits include quick reaction times, large product yields, and straightforward catalyst and product separation through easy steps.

2.
Front Chem ; 10: 1001707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262344

RESUMO

We applied the Petasites hybridus rhizome water extract as green media so that Ag/Fe3O4/CdO@ multi-walled carbon nanotubes magnetic nanocomposites (Ag/Fe3O4/CdO@MWCNTs MNCs) could be prepared. We also evaluated its activity by using in the one-pot multicomponent reaction of acetophenones, diethyl oxalate, ammonium acetate, and activated carbonyl compounds such as ninhydrin, isatin and acenaphthylene-1,2-dione, and malononitrile and hydrazoyl chlorides in an aqueous medium at room temperature for the generation of spiro-1,2,4-triazines as new derivatives with tremendous output. Moreover, reducing organic pollutants from 4-nitrophenol (4-NP) was carried out by generating Ag/Fe3O4/CdO@MWCNTs in water at room temperature. The results displayed that Ag/Fe3O4/CdO@MWCNTs reduced pollutants of organic compounds in a short time. The synthesized spiro-1,2,4-triazines have NH and OH functional groups having acidic hydrogen with high antioxidant power. Also, the spiro-1,2,4-triazines exhibited antimicrobial ability. For this purpose, the disk diffusion method was applied and two kinds of bacteria, Gram-positive and Gram-negative, were employed for the analysis. Furthermore, we applied functional theory-based quantum chemical methods in order to better understand reaction mechanism density. To generate spiro-1,2,4-triazines, the applied process showed many properties such as reactions with short time, products with good yields, and simple extraction of catalyst from a mixture of reactions.

3.
J Hazard Mater ; 403: 123716, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264894

RESUMO

In the present study, a new class of hierarchical silica based imprinted mesoporous polymers was fabricated by ion imprinting technology and it was applied to simultaneous selective extraction of cadmium and lead ions by micro solid phase extraction (µ-SPE). The biological nanocrystalline cellulose (BNCC) was prepared via acid catalyzed hydrolysis of cotton wool. The hierarchical silica (HS), as a substrate material, was synthesized via dual-template method, using BNCC and cetyltrimethylammonium bromide (CTAB) as hard and soft templates respectively. The structure and functional groups was characterized by Fourier infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD) and nitrogen adsorption-desorption. The results indicate that the as-prepared material has a hierarchical mesoporous structure with high specific surface area and high adsorption capacity for Cd(II) and Pb(II). The optimum experimental conditions in the proposed procedure were determined by response surface methodology (RSM) based on Box Behnken Design (BBD) and then it was successfully applied to determine Cd(II) and Pb(II) ions in the river water and fish samples.


Assuntos
Impressão Molecular , Polímeros , Adsorção , Animais , Cádmio/análise , Íons , Chumbo , Músculos/química , Projetos de Pesquisa , Rios , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Água
4.
Comb Chem High Throughput Screen ; 24(9): 1465-1475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33030128

RESUMO

AIMS AND OBJECTIVE: In the current study, environmentally benign and cost-effective procedures were suggested for the preparation of carboxy group functionalized imidazolium salts, including [Cmmim]BF4 - or [Cmmim]Br- as a new, reusable Brønsted acidic ionic liquid (BAIL) catalyst. Then, the catalytic performance of [Cmmim]BF4 - or [Cmmim]Br- were successfully inspected towards the three---components one---pot preparation of pyrano[2,3-d]pyrimidinone derivatives 4a-4q. The mentioned procedures show short reaction times, easy work-up procedure, green conditions, high yields of the products, high potent of recovering, and reusing capability. The current study is useful and adequate for the application and development of imidazolium salts on the basis of green chemistry principles. MATERIALS AND METHODS: An aromatic aldehyde (1 mmol), barbituric acid (1 mmol), and malononitrile (1 mmol) were placed in a round---bottomed flask containing ethanol (5 mL). BAILs A and B (0.1 mmol, 10 mol%) were added to the mixture. The suspension was magnetically stirred at room temperature for an appropriate time (Table 2). After completion of the reaction, which was monitored by TLC (n---hexane:ethyl acetate = 3:1), the pure product was filtered off to separate the catalyst, washed with water, and recrystallized from ethanol to afford the pure compound. After separation of the product, the catalyst was recovered by evaporation of water, washed with Et2O, dried under vacuum for 2 h, and reused for the same reaction. RESULTS: The mentioned procedure shows short reaction times, easy work-up procedure, green conditions, high yields of the products, and high potent of recovering and reusing capability. CONCLUSION: In this study, we unveiled the synthesis of a new acetic acid functionalized ionic liquids [Cmmim]BF4 - BAIL A or [Cmmim]Br- BAIL B and their application for the preparation of pyrano[2,3-d]pyrimidinone derivatives via a three-component reaction among various aromatic aldehydes, barbituric acid, and malononitrile under mild and metal-free conditions. A wide range of pyrano[2,3-d]pyrimidinone derivatives bearing diverse functional groups was obtained in short reaction and excellent yields. Operational simplicity, recoverability, and reusability of catalysts, cheap and chemically stable reagents, high catalytic activity, easy work-up, and the eco-friendly procedure, make this method environmentally benign and cost-effective.


Assuntos
Imidazóis/química , Piranos/síntese química , Pirimidinonas/síntese química , Imidazóis/economia , Estrutura Molecular , Piranos/química , Piranos/economia , Pirimidinonas/química , Pirimidinonas/economia , Sais/química , Sais/economia
5.
Nat Prod Res ; 34(7): 923-929, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30587038

RESUMO

A three-component Strecker-type reactions was applied for the synthesis of benzofuran derivatives through the reaction of 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone (euparin), primary amines and trimethylsilyl cyanide (TMSCN) in the presence of catalytic amount of ZnO-nanorods (ZnO-NR) and piperidine in acetonitrile at room temperature. The method has proved to be synthetically simple, and effective with high atom economy and yield. The catalyst also revealed significant reusability. Moreover, the antioxidant activity and free radical scavenging capacity of the newly synthesized such as 4a, 4c, 6a and 6c was screened using free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays and compared with hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ). These compounds exhibit good DPPH radical scavenging and ferric reducing antioxidant power (FRAP) assays.


Assuntos
Antioxidantes/farmacologia , Benzofuranos/síntese química , Antioxidantes/síntese química , Antioxidantes/química , Benzofuranos/química , Benzofuranos/farmacologia , Catálise , Sequestradores de Radicais Livres/química , Ferro/química , Óxido de Zinco
6.
Mol Divers ; 24(1): 81-91, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30830596

RESUMO

An efficient procedure for the synthesis of benzochromene derivatives employing 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone (euparin), aldehydes, alkyl bromides, dialkyl acetylenedicarboxylate and triphenylphosphine in the presence of KF/CP NPs as a heterogeneous base nano-catalyst in water at 80 °C is investigated. Also, the antioxidant activity of some synthesized compounds was studied. The workup of mixture of reaction is simple, and the products can be separated easily by filtration. KF/CP NPs showed a good improvement in the yield of the product and displayed significant reusable activity.


Assuntos
Antioxidantes/síntese química , Técnicas de Química Sintética , Cromanos/síntese química , Química Verde , Nanopartículas , Zeolitas/química , Antioxidantes/química , Antioxidantes/farmacologia , Catálise , Cromanos/química , Cromanos/farmacologia , Ferro/química
7.
Nat Prod Res ; 33(11): 1617-1623, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29376428

RESUMO

A novel class of benzofuran derivatives is prepared from the isocyanide-based MCR, euparin and aldehydes in the presence of ZnO-nanorods as a catalyst in excellent yields at room temperature under solvent-free conditions as a green reaction medium. Also, the antioxidant activities of some synthesised compounds such as 4a, 4b, 10a and 10b were evaluated by DPPH radical scavenging and ferric reduction activity potential (FRAP) assays. Compound 10b, was shown moderate radical scavenging activity and very good reducing activity compared to standards (BHT and TBHQ).


Assuntos
Antioxidantes/farmacologia , Benzofuranos/síntese química , Benzofuranos/farmacologia , Petasites/química , Antioxidantes/síntese química , Benzofuranos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/farmacologia , Química Verde , Ferro/química , Óxido de Zinco/química
8.
Iran J Pharm Res ; 12(2): 395-400, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24250614

RESUMO

Two flavones, ladanein and 6-hydroxy-5,7,4'-trimethoxyflavone and one labdane-type diterpene, ent-13-epi-manoyloxide, were isolated from an ethyl acetate-methanol extract of the aerial parts of Salvia sharifii. The compounds were purified using several chromatographic methods. Structural elucidation of the compounds was performed using their (1)H and (13)C-NMR data, EI mass and UV spectral data. The compounds have been subjected to antimicrobial, antioxidant and cytotoxic activity. The diterpene showed higher cytotoxic activity than the flavones while the later compounds were better antioxidants compared with the isolated diterpene.

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