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Electrocatalytic multicomponent transformation of 6-aminouracils, aromatic aldehydes and malononitrile in ethanol in an undivided cell in the presence of potassium bromide as an electrolyte leads to 7-amino-pyrido[2,3- d]pyrimidine-6-carbonitrile derivatives in short reaction times (8-20 min) and good to high yields (70-86%).

In this research, new derivatives of spirooxadiazepines were prepared using multicomponent reactions (MCRs) of ninhydrin, secondary amines, Melderum's acid, carbonyl compounds such as aldehyde or ketones and hydrazonoyl chloride in water at room temperature in the presence of baker's yeast as catalyst in good yields. The short time of reaction, high yields of product, and easy separation of them are some advantages of this procedure. Another work in this research is investigation of antioxidant property of some synthesized compounds by diphenyl-picrylhydrazine (DPPH) radical trapping experiment. Presently, bacteria that are not destroyed with drug have generated many problems in the performance of many transferable disease. For this reason, discovering appropriate and new procedures for the dealing with these pathogens are important and recent study have focused on the investigation of the antibacterial effects on the prepared compounds. Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication, and applications of chemical products. Among solvents, water is a green solvents and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvent. [ABSTRACT FROM AUTHOR]

In this study, baker's yeast promoted one-pot synthesize of new 1,2,4-triazolpyrimidooxadiazole derivatives in high yields using multicomponent reactions of isatins, guanidine, alkyl bromides, aldehydes and hydrazonoyl chlorides in the presence of baker's yeast as a high performance catalyst in water at room temperature. Investigation of antioxidant ability of synthesized compounds using radical trapping of diphenyl-picrylhydrazine (DPPH) and ferric reduction power experiment is another purpose in this research. Also, the antimicrobial activity of some synthesized compounds proved by employing the disk diffusion test on Gram-positive and Gram-negative bacteria. This procedure has some benefits such as short reaction time, product with excellent yields and simple, efficient, inexpensive, and environment-friendly catalyst. Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication and applications of chemical products. Among solvents, water is a green solvents and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvent. 1,3,4-Oxadiazoles are a known class of compounds, reported to exhibit antibacterial, antifungal, analgesic and anti-inflammatory, anticonvulsant, hypoglycemic, and anticancer activities. [ABSTRACT FROM AUTHOR]

In this research a new derivatives of 3,3,5-trichloroisatins and 3,3-dichloroisatins were synthesized in good yields using catalyst-free one-pot reaction of isatins or N-alkylisatines, triphenylphosphine and carbon tetrachloride in acetonitrile at room temperature. Because of existing isatin core in synthesized compounds, the antioxidant activity was investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and power of compounds for reducing of ferric ion experiments and comparing the results with synthetic antioxidants (TBHQ and BHT). Easy, simple, fast and new procedure are the some advantages of this study. Heterocyclic system carrying indolin-2-one moiety has drawn tremendous interest of researchers in the area of synthetic organic and medicinal chemistry. During past decades, modifications mainly been made at the C-3 position of indolin-2-one and numerous compounds have been reported as drugs for treating various kinds of diseases. This easy separation of products with high yields and short time of reaction makes this protocol attractive and useful as an industrially viable. [ABSTRACT FROM AUTHOR]

In this study, water extract of Spinacia oleracea leaves was used for the synthesis of Fe3O4/TiO2/MWCNTs magnetic nanocomposites and high performance of this catalyst was confirmed by employing it in the solvent-free multicomponent reactions of anilines, oxalyl chloride, diamines or hydroxyamines, electron-deficient acetylenic ester, α-haloketones and Et3N at room temperature for the generation of new spiropyrroloindoles in high yields. This catalyst could be utilized several times and has a significant role in the yield of product. The synthesized spiropyrroloindoles have NH and OH group in their structure and for this reason have good antioxidant activity. Also, by employing Gram-positive and Gram-negative bacteria and the disk diffusion procedure confirmed the antimicrobial effect of some spiropyrroloindole derivatives. The results showed that synthesized spiropyrroloindoles prevented the bacterial growth. This used process for preparation of new spiropyrroloindoles has some improvements such as low reaction time, product with high yields, and simple separation of catalyst and products. [ABSTRACT FROM AUTHOR]

For instance, stepped impedance resonators, open-ended stubs, short-ended stubs, coupled lines and ring resonators can be used for designing of coupler and power dividers. Keywords: compact size; harmonic suppression; microstrip coupler; open-ended stubs; T-shaped resonators EN compact size harmonic suppression microstrip coupler open-ended stubs T-shaped resonators 255 263 9 05/09/22 20220601 NES 220601 1 Introduction Branch-line coupler (BLC) is an important device in the modern wireless and communication circuits. As graphically explained in Figure 6, the presented T-shaped resonator and two open-ended stubs resonator are combined to form the main resonator. [Extracted from the article]

In this work, a novel and simple catalytic system including FeCl2, PPh3 and potassium tert-butoxide has been employed for the synthesis of imines from amines. In order to prove the catalytic acceptorless dehydrogenation pathway for this transformation, the liberated H2 gas is detected by NMR spectroscopy. By utilizing this protocol, a variety of arylamines were used successfully for the preparation of corresponding imines in good to excellent yields (on a 1 mmol scale, 73–91% yield for homocoupling, 71 and 91% for heterocoupling). [ABSTRACT FROM AUTHOR]

The monoamine oxidase B (MAO‐B) depicts an attractive drug target for the development of neuro protective agents toward the treatment of neurodegenerative diseases. The current study involved synthesis, in silico and cytotoxic evaluation of N1‐alkylated‐5‐substituted 3‐imino isatin derivatives with the proposed MAO‐B inhibitory activities. The In silico molecular modeling investigation was performed through the induced fit docking, molecular mechanics‐generalized born surface area, and molecular dynamic method in order to uncover the binding mode interaction and their proposed impact on the active site environment and flexibility. The synthesized compounds were characterized by spectroscopic methods. Compound 3‐Imino‐1‐pentyl indolin‐2‐one (3h) with the highest free binding energy adopts an extended conformation spanning from the flavin ring location to the entrance of the substrate cavity. In this way, Ile199 adopts the "open" conformation so the two separate cavities of MAO‐B active site fused and formed a single‐space, which abled the compound extending to the MAO‐B entrance cavity space. From consideration of the data presented in this paper, we reveal that longer N1‐alkylated‐3‐imino isatin derivative could be proposed as inhibitor that would occupy both cavities of the MAO‐B active site. Furthermore, the mentioned derivatives provided acceptable drug profiling based on in silico ADME calculation and MTT cytotoxicity test evaluation. [ABSTRACT FROM AUTHOR]

11-(1H-Pyrrol-1-yl)-11H-indenol[1,2-b]quinoxaline and 3-(1H-pyrrol-1-yl)indolin-2-one derivatives are synthesized in good yields in a novel, one-pot, and efficient process by condensation of 11H-indenol[1,2-b]quinoxalin-11-one or isatin derivatives with 4-hydroxyproline on solid-support montmorillonite K10 under microwave irradiation.

A strategy of efficient and convenient green synthesis for the preparation of tetrahydroisoquinolonic acids in three-component cyclocondensation reaction of homophthalic anhydride, aldehydes, and amines using the inexpensive, nontoxic, and easily available KAl(SO4)2.12H2O catalyst is described. This reaction is stereoselective in the preparation of cis-isoquinolonic acids.

Using density functional theory calculations (based on the B3LYP/6-31G(d) method), we investigated the functionalization of a BN nanosheet (B33N33H22) by different α-amidino carboxylic acids (ACA). It was found that the pristine BN sheet can be noncovalently functionalized by the ACA with an adsorption energy of about − 2.7 kcal/mol. Also, the results showed that structural Stone–Wales (SW) defects significantly increase the adsorption energy. The SW-BN nanosheet transforms from an insulator to a semiconductor by covalent functionalization. Incorporating –NH2 and –NO2 groups in the structure of the ACA molecule increases and decreases the adsorption energy, respectively. The –NH2 group compared to the –NO2 was found to be more favorable for covalent functionalization especially when it is substituted at the meta position of phenyl group of ACA molecule. Investigating the effect of some other electron donating groups showed that the favorability order of applied groups for functionalization is as follows: –N(CH3)2 > –OH > –NH2 > –OCH3 > –Phenyl > –F. Furthermore, it was found that the solubility of BN nanosheets significantly increases, depending on the type of functional group. [ABSTRACT FROM AUTHOR]

We present a one-pot method for the synthesis of 2,3-dihydroquinazoline- 4(1H)-ones. The three-component reaction between isatoic anhydride, primary amines, and dialkyl acetylenedicarboxylates in the presence of N-sulfonic acid pyridinium chloride under solventfree conditions affords the corresponding alkyl 2-[(alkoxycarbonyl) methyl]-1,2,3,4-tetrahydro-3-alkyl-4-oxo-quinazoline-2-carboxylates in excellent yields. [ABSTRACT FROM AUTHOR]

A facile and direct synthesis of pyrimido[2,1-b][1,3]thiazin-6-ones via a one-pot, three-component reaction of dialkyl acetylenedicarboxylates with alkyl or aryl isocyanides and 2-thioxopyrimidin-4-ones in good overall yields. [ABSTRACT FROM PUBLISHER]

An efficient method has been developed for the synthesis of 1,8-dioxo-octahydroxanthene derivatives in two-step. In the first step, the electrogenerated base (EGB) catalyzed multicomponent transformation of dimedone and aromatic aldehydes in an undivided cell in the presence of sodium bromide as an electrolyte into 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) at room temperature. In the second step, H2SO4 was employed as a dehydrating reagent for the cyclization process to give symmetrical heterocycles 1,8-dioxo-octahydroxanthene derivatives. Short reaction time, convenient work up, and using of inexpensive reagents, simple equipment, novel and eco-friendly procedure make this strategy more useful for the preparation of xanthene derivatives. [ABSTRACT FROM AUTHOR]

Novel pyrimido[4,5-b]quinoline-tetraones were prepared by the three-component reaction of 2-hydroxynaphthalene-1,4-dione, 6-amino-uracils, and aromatic aldehydes in aqueous media and catalyzed byp-toluenesulfonic acid. This protocol provides a simple one-step procedure with the advantages of easy workup, good yield of products, and environmental friendliness. [ABSTRACT FROM PUBLISHER]

The article describes ionic liquids [bmim][NO3] in the presence of 30% mol CuI as efficient media for the domino Knoevenagel–hetero–Diels–Alder reaction ofo-propargyloxy benzaldehydes as unactivated terminal alkynes with some active methylene compounds. Short reaction time, easy workup, good to excellent yields, and mild conditions are advantages of this new media. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®to view the free supplemental file. [ABSTRACT FROM AUTHOR]

Quinoxaline derivatives are compounds with pharmaceutical applications. In this study, derivatives of N1-(11H-indeno[1,2-b]quinoxalin-11-ylidene)benzene-1,4-diamine were synthesized and attached to carboxylated multi-wall nanotubes (MWNT-COOH). Functionalized carbon nanotubes were characterized by scanning electron microscopy (SEM) to study the shape of structures, transmission electron microscopy (TEM), fast Fourier transform infrared (FT-IR), Raman spectroscopy, and elemental analysis. [ABSTRACT FROM AUTHOR]

Urea polyfunctional derivatives were successfully synthesized via a one-pot, five-component nucleophilic addition/Ugi reaction sequence. Simplicity, solvent-free conditions, and good yields of products are advantages of this method. [ABSTRACT FROM PUBLISHER]

We found that elemental iodine and bromine are converted to trihalide nucleophiles (triiodine and tribromide anion, respectively) in the presence of catalytic amounts of meso-tetraphenylporphyrins (H2TPP). Therefore a highly regioselective method for the synthesis of β-haloalcohols through direct ring opening of epoxides with elemental iodine and bromine in the presence of H2TPPs as new catalysts is described. At room temperature a series of epoxide derivatives were converted into the corresponding halohydrins resulting from an attack of trihalide species anion atoms at the less substituted carbon atom. This method occurs under neutral and mild conditions with high yields in various aprotic solvents, even when sensitive functional groups are present. [ABSTRACT FROM AUTHOR]

In this paper, the microwave-induced chemical functionalization of carboxylated multi-walled carbon nanotubes (MWNT-COOH) by 2,3-diaminopyridine, have been investigated. The major advantage of this high-energy procedure is reducing the reaction time to the order of minutes and the number of steps in the reaction procedure compared to that of conventional functionalization processes. These functionalizations involve amidation and cycloaddition reactions, respectively. The amidation was completed in one step as compared to two in the conventional approach. The acid chloride formation step was eliminated here. The cycloaddition of MWNTs with triphenylphosphite to producing MWNT-4-azabenzimidazole was carried out in 20 minutes under microwave conditions, and the results were similar to what was achieved in 4 days using conventional methods. The interesting point is that modified MWNT can be homogeneously dispersed in DMF without sonication and the dispersed MWNT does not sediment in 1 month. The results are confirmed by FT-IR, SEM, RAMAN, TGA, DTA and elemental analysis. [ABSTRACT FROM AUTHOR]

Tetrahydroindeno [1,2-b]pyrrole-3-carboxylate were synthesized in a one-pot procedure by the reaction of 1,3-dicarbonyl and activated carbonyl compounds such as benzyl or ninhydrin in ethanol/water in the presence of ammonium acetate. J. Heterocyclic Chem., (2011). [ABSTRACT FROM AUTHOR]

The multicomponent, one-pot reaction of dialkyl acetylenedicarboxylates with 2,3-dihydrophthalazine-1,4-dione in the presence of triphenyl phosphite or trialkyl phosphites leads to stable substituted phosphorylsuccinates in good yields. GRAPHICAL ABSTRACT [ABSTRACT FROM PUBLISHER]