Six-component synthesis and biological activity of novel spiropyridoindolepyrrolidine derivatives: A combined experimental and theoretical investigation.

Petasites hybridus rhizome water extract was used as green media for the preparation of Ag/Fe3O4/CdO@multi-walled carbon nanotubes magnetic nanocomposites (Ag/Fe3O4/CdO@MWCNTs MNCs), and its activity was evaluated by using in the one-pot multicomponent reaction of isatins, acetyl chloride, secondary amines, vinilidene Meldrum's acid, primary amines, and malononitrile in an aqueous medium at room temperature for the generation of spiropyridoindolepyrrolidine as new derivatives with tremendous output. In addition, organic pollutant reduction of 4-nitrophenol (4-NP) was carried out by generated Ag/Fe3O4/CdO@MWCNTs in water at room temperature. The results displayed that Ag/Fe3O4/CdO@MWCNTs were reduced as pollutants of organic compounds in a short time. The synthesized spiropyridoindolepyrrolidine has an NH2 functional group that has acidic hydrogen and shows high antioxidant ability. Also, the spiropyridoindolepyrrolidine exhibited antimicrobial ability, and the method that is used for this purpose is the disk diffusion method, and two kinds of bacteria, Gram-positive and Gram-negative, were employed for this analysis. Also, to better understand the reaction mechanism density, functional theory-based quantum chemical methods have been applied. For the generation of spiropyridoindolepyrrolidine, the used process has many properties such as reactions with short time, product with good yields, and simple extraction of catalyst from the mixture of reaction.

Highly Efficient Reusable Carboxy Group Functionalized Imidazolium Salts for a Simple and Cost-effective Preparation of pyrano[2,3-d]pyrimidinone Derivatives.

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.

Bio-Fe3O4 Magnetic Nanoparticles Promoted Green Synthesis of thioxo- 1,3-Oxazole Derivatives: Study of Antimicrobial and Antioxidant Activity.

AIMS AND OBJECTIVE: In this work, 1,3-oxazoles were generated using the multicomponent reaction of α-bromo ketones, alkyl (aryl) isothiocyanates, sodium hydride and Fe3O4 MNPs in the water at room temperature in good yields. The nanoparticles generated via the biosynthesis method have potential value in different purposes, such as organic synthesis. MATERIALS AND METHODS: To study the antioxidant ability of some synthesized thioxo-1,3-oxazoles, diphenyl-picrylhydrazine (DPPH) radical trapping and power of ferric reduction testes are employed. Among the studied thioxo-1,3-oxazoles, compound 4b have good power for radical trapping and reduction activity than the standard antioxidants such as BHT and TBHQ. In addition, the antimicrobial activity of some thioxo-1,3-oxazoles was studied, employing the disk diffusion test on Gram-positive bacteria and Gram-negative bacteria. The results of the disk diffusion test showed that compounds 4a, 4b, 4d and 4f prevented bacterial growth. RESULTS: Without employing catalyst, these reactions have low yield and busy mixture. The synthesis of compound 4a as sample reaction has a similar yield in the presence of ZnO-NPs and Fe3O4 MNPs (entry 20 and entry 30), but the removal of catalyst from the mixture of reaction after the completion of the reaction is comfortable in the presence of Fe3O4 MNPs. Structures of compound 4a-4i are confirmed by IR, 1H NMR and 13C NMR mass spectra. CONCLUSION: The reaction of α-bromo ketones, isothiocyanate and sodium hydride in the presence of the catalytic amount of Fe3O4 MNPs in water generates 1,3-oxazole derivatives in good yields. Some of the advantages of performing these reactions with the present procedure are to carry out these reactions in water as a green solvent and simple removal of catalyst.

ZnO-nanocatalyst Promoted the Production of Imidazole Derivatives via four-component Reaction of Aminoacid: Study of Antioxidant and Antimicrobial Activity.

AIM AND OBJECTIVE: In current research, imidazole derivatives are synthesized via a new process of four component reaction of trichloroacetonitrile, amides, alkyl bromides and amino acids catalyzed by zinc oxide nanoparticles (ZnO-NPs) as a simple and recyclable catalyst in water at room temperature. Among investigated compounds, compounds 5b have good results relative to butylated hydroxytoluene (BHT) and 2-tert-butylhydroquinone (TBHQ) as standard antioxidant. The achieved outcomes of disk diffusion experiment showed that these compounds avoided the growth of bacterial. MATERIALS AND METHODS: In this research, all chemicals are purchased from Fluka (Buchs, Switzerland) and employed with any purification. For measuring infrared spectroscopy and melting point, a Shimadzu IR-460 spectrometer and Electrothermal 9100 apparatus are utilized respectively. BRUKER DRX-400 AVANCE spectrometer is used for giving the 1H, and 13CNMR spectra at 400.1 and 100 MHz respectively. For recording mass spectra, A FINNIGAN-MAT 8430 spectrometer with an ionization potential of 70 eV was utilized. The scanning electron microscopy (SEM) employing a Holland Philips XL30 microscope was used for determination of ZnO nanocomposites morphology. X-ray diffraction (XRD) analysis at room temperature using a Holland Philips Xpert X-ray powder diffractometer, with CuKα radiation (λ=0.15406 nm), with 2θ ranging from 20 to 80° was employed for characterization of crystalline structure of Fe3O4/CuO nanocomposites. Scherrer's formula; D= 0.9λ/ß cosθ was employed for calculating the average crystallite size where D is the diameter of the nanoparticles, λ (CuKα) =1.5406 Å and ß is the fullwidth at half-maximum of the diffraction lines. A general way to prepare of compounds 5 The trichloroacetonitrile 1 (2 mmol) and amides 2 (2 mmol) mixed with ZnO-NPs (10 mol%) in water (5 mL). after 45 min amino acids 3 (2 mmol) was added to previous mixture at room temperature. After 30 min α-haloketones 4 (2 mmol) was added to mixture and stirred for 3 h. After 3 h, the reaction is completed and TLC confirms progress of the reaction. At last, the solid residue was collected by filtration and cleaned with EtOAC to removing ZnO-NPs and after evaporating solvent and washing solid with Et2O compounds 5 afforded as pure product. RESULTS: Without employing catalyst, these reactions have low yield and busy mixture. The synthesis of compound 5a as sample reaction and displayed the ZnO nanoparticles (10 mol%) is the best catalyst for sample reaction and H2O is the very better than other solvent in sample raection. Structures of 5 are confirmed by IR, 1H NMR, 13C NMR mass spectra. CONCLUSION: In summary, imdazole derivatives were produced in excellent yield from the reaction of trichloroacetonitrile, amides, alkyl bromides and amino acids using ZnO-NPs in water at room temperature. In addition, the power of synthesized imidazole as antioxidant was determined by radical trapping of DPPH and power of reducing ferric analyzes. The tested imidazoles display good radical trapping of DPPH but exhibitted moderate FRAP relative to BHT and TBHQ as synthetic antioxidants.The outcomes of disk diffusion experiment exhibite that synthesized imidazole avoided the bacterial growth. The superiorities of this procedure are environmental, high yield of product and low amounts of catalyst and short time of reaction.

Withdrawn Notice: Green Synthesis of Furo-1,3-oxazole Derivatives using Fe3O4-MNPs as Efficient Nanocatalyst: Study of Antimicrobial Activity

The article has been withdrawn at the request of the authors and editor of the journal Combinatorial Chemistry & High Throughput Screening.Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused. BENTHAM SCIENCE DISCLAIMER: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

KF/Clinoptilolite Nanoparticles as a Heterogeneous Catalyst for Green Synthesis of pyrido[2,1-a]isoquinolines using Four-Component Reaction of Alkyl Bromides.

OBJECTIVE: KF/Clinoptilolite nanoparticles are employed as a heterogeneous catalyst for the preparation of pyrido[2,1-a]isoquinoline derivatives through a four-component reaction of isoquinoline, two different alkyl bromides and an electron deficient internal alkynes at ambient temperature in water as green solvent. METHODS: In this research, (2,2-Diphenyl-1-picrylhydrazyl) radical trapping and reducing potential of ferric ion experiments was used for determining antioxidant activity of some newly synthesized compounds such as 5a, 5c, 5f and 5g and comparing results with synthetic antioxidants (TBHQ and BHT). RESULTS: Compounds 5a, 5c, 5f and 5g display trace DPPH radical trapping and excellent reducing power of ferric ion. Furthermore, the power of some prepared compounds against Gram-positive and Gram-negative bacteria was proved by employing the disk dispersion experiment. CONCLUSION: The obtained results of disk diffusion test showed that compounds 5a, 5d and 5e prevented the bacterial growth. The reported procedure shows the advantages of clean reaction, high yield and simple purification.

Regioselctive Thiocyanation of Aromatic and Heteroaromatic Compounds Using a Novel Bronsted Acidic Ionic Liquid.

A convenient procedure for the preparation of 1-(1-Propylsulfonic)-3- methylimidazolium thiocyanate as a novel Brønsted acidic ionic liquid thiocyanation agent and highly efficient heterogeneous catalytic is described. This catalyst is used in regioselective thiocyanation of indoles, anilines, pyrroles and their derivatives (aromatic and heteroaromatic organic compounds) in the presence of H2O2 as a mild and oxidant in EtOH:H2O (1:1 v/v). These reactions are performed under mild and simple conditions and give regioselective products in high yields and short reaction time.

Synthesis of 9H-furo [2,3-f]Chromene Derivatives by Promoting ZnO Nanoparticles.

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.

ZnO-nanorods as the catalyst for the synthesis of 1,3-thiazole derivatives via multicomponent reactions.

Environmentally method for the synthesis of 1,3-thiazole has been achieved by multicomponent reactions of primary amines, isothiosyanates and alkyl bromides under solvent-free conditions using nanorod ZnO structures as catalyst. These reactions were not performed without catalyst. The catalyst showed significant reusable activity.

Green synthesis of phosphoryl-2-oxo-2H-pyran via three component reaction of trialkyl phosphites.

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.

Synthesis of unsaturated α-acyloxybenzothiazoleamides via the Passerini three-component reaction.

4-Benzothiazol-2-ylamino-4-oxo-2-butenoic acid, prepared from reaction of 2-aminobenzothiazole and maleic anhydride, are used as an acid component in Passerini three-component reaction, under solvent-free media, to produce unsaturated α-benzothiazole acyloxyamides in good yields.