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This study extensively describes the synthesizing and characterizing of new β-enaminone complexes derived from dimedone and amines coordinated with transition metals Fe(II), Co(II), Ni(II), and Cu(II), also two ligand's metformin (Met) and 8-hydroxyquinoline (8-hq). These were determined via FT-IR, 1H-NMR, electron and mass spectroscopy, molar electrical conductivity, thermal analysis (TGA, DTA and DSC) and characterized by metal content determination (%), magnetic susceptibility and elemental analysis (C.H.N.) and SEM technique. The measurements indicate that the complexes have six coordination numbers, where the β-enaminone is coordinated as tetradentate ligand through the two nitrogen atoms and the two oxygen atoms beside metformin is coordinated through the two nitrogen atoms and 8-hydroxyquinoline is coordinated by oxygen and nitrogen atoms as bidentate ligands. The conductance suggests that all complexes have electrolytic behavior, being conductive in a ratio of (1:2). SEM results revealed the presence of nanostructures on sample surfaces. The biological activity of the prepared ligands and complexes are studied in different concentrations for four types of bacteria Staphylococcus aureus has (+G) and Escherichia coli, Pseudomonas aeruginosa, Klebsiella have (-G), well as, the influence of the fungus. The ligands have disparate effectiveness while complexes have high effectiveness inhibiting the bacteria and fungus. [ABSTRACT FROM AUTHOR]

The work presented a facile, one-step procedure as a green assembly process for preparing silver tungstate nanorod by hydrothermal technique via a chemical reaction between silver nitrate and sodium tungstate. The synthesized precipitate was characterized using X-ray diffraction (XRD) transmission electronic microscope (TEM) and scanning electron microscopy (SEM) to ensure the formation of crystallization and single-phase material. The prepared nanorods undergo a catalytic evaluation to synthesize tetrahydrobenzo[a] xanthene-11-one derivatives by a one-pot reaction of β-naphthol, dimedone, and aromatic aldehyde with a catalytic amount of silver tungstate under the solvent-free condition at 60–70 °C. ArgC is one of the L-arginine biosynthetic pathways of mycobacterium tuberculosis. The molecular docking explains that all the synthesized compounds presented high ligand ability for the targeted enzyme compared with xanthene-9-carboxylic acid as a reference. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis and application of a novel catalyst for carbon–carbon bond formations, comprising palladium immobilized on 2-(5-hydroxyquinolin-8-yl)-1H-benzo[d]imidazole-5-carboxylic acid modified superparamagnetic iron oxide nanoparticles (Pd@HQBI-SPION). The synthesis involved the attachment of HQBI ligands to SPION using APTES, followed by the immobilization of palladium. Characterization techniques, including FTIR, TEM, and magnetic measurements, confirmed the successful synthesis and structural integrity of Pd@HQBI-SPION. The catalytic activity of Pd@HQBI-SPION was evaluated in various carbon–carbon bond formation reactions, demonstrating high efficiency and reusability. 8 different derivatives bearing several electron withdrawing and electron donating functionalities were used as starting materials and the products were obtained in high isolated yields (75–97%). The catalyst exhibited excellent performance in one-pot synthesis of phenanthroline-dimedone polycyclic derivatives via C-alkylation followed by intramolecular O-alkylation of phenanthroline with dimedone. The products are obtained in high to excellent yields is described. This protocol presents a highly selective synthetic method for the construction of polycyclic aromatic compounds containing nitrogen and oxygen atoms. [ABSTRACT FROM AUTHOR]

AbstractA nickel ferrite nanocatalyst was synthesized in the presence of simple and cost-effective polysorbates assisted sol gel method as an effective catalyst has been successfully used for one pot multicomponent Hantzsch condensation reaction of different aromatic aldehydes, dimedone and ammonium acetate under solvent-free condition at 110 °C-120 °C. The highlights feature for the synthesis of acridinediones are the recyclability of catalyst, solvent-free reaction condition, use of inexpensive catalyst, highly efficient, facile product isolation, clean reaction, nontoxic substances and great yields in short reaction time. The recovered catalyst can run four times without loss its activity. [ABSTRACT FROM AUTHOR]

An operationally simple, cost-effective, and environmentally benign method has been described for the synthesis of various polysubstituted benzoxanthenes via L-proline-catalyzed three-component condensation of β-naphthol, aromatic aldehydes, dimedone, or 2-hydroxy-1,4-naphthoquinone in aqueous medium. This process has additional benefits such as simple product isolation and purification techniques, good to higher yields, and above all, efficient catalyst reusability. The addition of sodium dodecyl sulfate is an extra benefit to speed up this reaction. [ABSTRACT FROM AUTHOR]

Copyright of Science Journal of University of Zakho is the property of Science Journal of University of Zakho and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A family of molybdenum complexes with a general formula of [MoO2L]2 have been synthesized and fully characterized, where L is a tridentate ONO Schiff base ligand featuring a Cl substituent in different positions on the aromatic ring of salicylidene‐2‐aminophenolato backbone. The solvent molecule stabilized the monomeric structure of [MoO2LD] (D = DMF or DMSO) allowing single‐crystal X‐ray diffraction of the three new complexes. The dimeric complexes are utilized to catalyze the reaction of aldehydes/ketones with dimedone, leading to 1,8‐dioxo‐octahydro‐xanthene derivatives in N,N‐dimethylformamide. We found that their catalytic activity is enhanced by the electron‐withdrawing group of the Cl substituent on the ONO ligand. In addition, the position of the Cl substituent can also positively influence the catalysis performance: (ortho (L1) > para (L3) > meta (L2) ≈ meta (L4)). The high efficiency of the catalysts promises high yields and selectivity with a low catalyst loading and allows a wide substrate scope of aldehydes/ketones for the reaction. In addition, the method employs recrystallization for purifying products and can be easily scaled up to gram levels, indicating a strong potential for industrial utilization. [ABSTRACT FROM AUTHOR]

Over the past two decades, acridinediones have attracted considerable attention in organic and medicinal chemistry, drug discovery, and materials science. The present review covers recent literature on the synthesis of acridine-1,8-dione derivatives, including cyclocondensation and multicomponent reactions. These compounds exhibit significant biological activity and have found application in the production of antimicrobial, anticancer, and anti-inflammatory drugs. They are also used in materials science, acting as fluorescent probes. Recent advancements have been focused on developing more efficient synthetic approaches to acridine-1,8-diones and exploring novel applications. The versatility and wide range of functionalities make acridine-1,8-dione derivatives valuable in both pharmaceutical and industrial fields, highlighting their potential for future research and development. [ABSTRACT FROM AUTHOR]

A new type of the four-component tandem Knoevenagel—Michael reaction was discovered, which used arylaldehydes, N,N′-dimethylbarbituric acid, dimedone, and morpholine or piperidine in organic solvents or in water. The reaction proceeded under mild conditions at room temperature with the formation of a new substituted unsymmetrical polycyclic ionic scaffold in 83–98% yields. The structures of the reaction products were confirmed by X-ray diffraction analysis on the example of two compounds. The further oxidative cyclization of the Knoevenagel—Michael reaction products led to unsymmetrical substituted dihydrofurans spiro-annulated with N,N′-dimethylbarbituric acid. The structures of the synthesized compounds were confirmed by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Since that hydroquinoline and acridine compounds serve as the fundamental building blocks for the synthesis of many different pharmaceuticals, they are among the most significant classes of chemical compounds that attract the interest of numerous researchers and pharmacologists. Therefore, in this research, The Hantzch reaction was used to prepare these types hydroquinoline and acridine derivatives of compounds, through the reaction of a number substituted benzaldehyde with demidone and α-β diketone substitutes by refluxed with sodium acetate in the presence of iodine and a 1-sulfo-4-(3-(Ferricoxide-Silicondioxide nanopowdertrioxisilyl)propyl) piperazinum-1,4-diphosphate as a catalyst to form 7,7- dimethyl -4,6,7,8-tetrahydroquinoline derivatives which is represented by compounds (1-12) or in the same way by react benzaldehyde substitutes react with demidone and 4-isopropyl cyclohexanone 1-one to form acridin derivatives represented by compounds (13 -17). All product compound are characterized using 1H-NMR spectra and the results confirmed the structures.

Sulfonic acid-supported vanillin/bis indolylmethane-functionalized Fe3O4@SiO2-Propyl NPs were prepared and characterized by FT-IR, XRD, FE-SEM, TEM, VSM, EDX, DLS, and TGA-DTG. The catalytic efficiency of the prepared nanoparticles was subsequently investigated for the effective synthesis of imidazoquinazolines via the one-pot condensation of 2-aminobenzimidazole, aryl aldehydes, and cyclohexanone or dimedone under solvent-free condition. Some thiazoquinazolines also were prepared via the multicomponent reaction of aldehydes, dimedone, and 2-aminobenzothiazol under solvent-free condition,. This avenue is really suitable because it makes a high yield of product, doesn't take too long, doesn't need harmful materials and solvents, its work-up is easy and the catalyst is reusable. [ABSTRACT FROM AUTHOR]

A series of new bis azo dyes were synthesized starting from aromatic diamine with S/SO2 bridges and cyclic-1,3-dicarbonyl groups; contain active methylene group, namely; 3,3-dimethyl-1,5-cyclohexadione (dimedone), 1,3-cyclohexadione and 2,2-dimethyl-1,3-dioxane-4,6-dione to give 1-6. Whether the reaction is complete and the purity of the compounds were checked with TLC. The structure of the newly synthezed compounds was investigated by using, FT-IR, 1HNMR, LC–MS/MS and UV–Visible spectrophotometric methods, CH3OH was used in the LC-MS/MS experiments, and the molecular masses of the compounds were seen as M and M+1 protonated in the spectrum. In the UV-Vis spectra of these compounds, the solvent effect by using different solvents and also the acid-base effect by adding HCl or KOH to the medium were investigated. The tautomeric equilibrium forms (enol-imine O-H….N, keto-amine O….H-N forms) of the compounds were investigated according to the electronic spectrum recorded in chloroform, dimethylformamide (DMF), acetic acid, and methanol solvents. The results of the UV-visible and 1H-NMR spectra indicated that the compounds in chloroform, dimethylformamide (DMF), acetic acid and methanol were found in the hydrazo tautomer (keto-amine O….H-N forms) of the proposed tautomeric forms.

A convenient synthetic procedure for the construction of novel dispirooxindole motifs was successfully developed by base-promoted three-component reaction of ammonium acetate, isatins and in situ-generated 3-isatyl-1,4-dicarbonyl compounds. The piperidine-promoted three-component reaction of ammonium acetate, isatins and the in situ-generated dimedone adducts of 3-ethoxycarbonylmethyleneoxindoles afforded mutlifunctionalized dispiro[indoline-3,2'-quinoline-3',3''-indoline] derivatives in good yields and with high diastereoselectivity. On the other hand, a similar reaction of the dimedone adducts of 3-phenacylideneoxindoles afforded unique dispiro[indoline-3,2'-pyrrole-3',3''-indoline] derivatives with a cyclohexanedione substituent. A plausible reaction mechanism is proposed to explain the formation of the different spirooxindoles.

In the current work, N,N′-bipyridyl (N- sulfonic acid) (N′- silica-n-propyl) propane mesylate/chloride bonded to Fe3O4 coated with bilayer silica ([BPSSPMCFS]) was used as a novel bi-functional inorganic-organic hybrid magnetic nanocatalyst to manufacture 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-diones under solvent-free conditions. The methods of field emission scanning electron microscopy (FE SEM), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analyses, thermal gravimetric analysis (TGA), vibrating sample magnetometry (VSM) and Brunauer-Emmett-Teller (BET) were used to identify this nanohybrid. The [BPSSPMCFS] produced the mentioned derivatives with great selectivity without producing side products, and besides this important feature, which has always been one of the main problems on the way to the synthesis of these compounds, it has significant advantages such as simple synthesis, the use of green media, large surface area, simple separation and workup, very suitable turnover number (TON) and turnover frequency (TOF) values, great reuse for several consecutive cycles without noticeably changing its catalytic activity, and short reaction time. Moreover, the hot filtration technique was used to examine and confirm the heterogeneous nature of [BPSSPMCFS]. [ABSTRACT FROM AUTHOR]

8-Aroyl-3,4-dihydro-1H-pyrrolo[2,1-с][1,4]oxazine-1,6,7-triones react with 5,5-dimethylcyclohexane-1,3-dione to form 8-aroyl-7-hydroxy-7-(2-hydroxy-4,4-dimethyl-6-oxocyclohex-1-en-1-yl)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-1,6(7H)-diones, the structure of which was confirmed by single crystal X-ray diffraction data. [ABSTRACT FROM AUTHOR]

A novel heterogeneous pumice supported perchloric acid catalyzed synthesis of tetrahydrobenzo[b]pyran has developed via multi-component condensation of aromatic aldehydes, dimedone and malononitrile. The catalyst was characterized by IR, XRD, EDS, SEM, and TGA techniques which confirmed the formation novel pumice supported perchloric acid. The present protocol proved to have numerous advantages like one-pot reaction, good yield, short reaction time, inexpensive catalyst, recyclability and reusability of the catalyst, simple experimental and work up procedure, and purification of targeted molecules without column chromatography. [ABSTRACT FROM AUTHOR]

Dimedone and its derivates are used as selective probes for the nucleophilic detection of sulfenic acids in biological samples. Qualitative analyses suggested that dimedone also reacts with cyclic sulfenamides. Furthermore, under physiological conditions, dimedone must compete with the highly concentrated nucleophile glutathione. We therefore quantified the reaction kinetics for a cyclic sulfenamide model peptide and the sulfenic acids of glutathione and a model peroxiredoxin in the presence or absence of dimedone and glutathione. We show that the cyclic sulfenamide is stabilized at lower pH and that it reacts with dimedone. While reactions between dimedone and sulfenic acids or the cyclic sulfenamide have similar rate constants, glutathione kinetically outcompetes dimedone as a nucleophile by several orders of magnitude. Our comparative in vitro and intracellular analyses challenge the selectivity of dimedone. Consequently, the dimedone labeling of cysteinyl residues inside living cells points towards unidentified reaction pathways or unknown, kinetically competitive redox species. Sulfenic acids in biological samples are indirectly detected by nucleophilic probes. Whether dimedone probes also detect cyclic sulfenamides is controversial and depends on kinetic competitions. Furthermore, dimedone probes have to compete with the highly abundant physiological nucleophile glutathione (GSH). Kinetic assays in vitro and in yeast challenge the specificity of dimedone and highlight the benefits of GSH competition assays. [Display omitted] • Glutathione kinetically outcompetes dimedone as a nucleophile. • Dimedone cannot discriminate between peptide sulfenic acids and cyclic sulfenamides. • The presence and detectability of cyclic sulfenamides could be highly pH-dependent. • Origin and relevance of dimedone-labeled peptides often remain to be analyzed. • Glutathione competition assays are recommended for nucleophilic probe development. [ABSTRACT FROM AUTHOR]

A convenient synthetic protocol for the construction of spiro[indoline‐3,3′‐quinoline]‐2,5′‐dione motifs was successfully developed by base promoted one‐pot three‐component reaction. In the presence of piperidine, three‐component reaction of ammonium acetate, aromatic aldehydes and the in situ generated 3‐isatyl 1,4‐dicarbonyl compounds, which were derived from base mediated addition of dimedone to 3‐methyleneoxindoles, resulted in two diastereoisomers of spiro[indoline‐3,3′‐quinoline]‐2,5′‐dione derivatives in good yields and with good diastereoselectivity. The stereochemistry of the reaction was clearly elucidated by isolation of two diastereomers and determination of several single crystal structures. [ABSTRACT FROM AUTHOR]

In this work, Fe3O4@nano-walnut shell/BIII (FNWSB), as a reusable and new catalyst was prepared and then characterized by FT-IR, XRD, FESEM, EDS-MAP, and TGA. This catalyst was used for synthesis of tetrahydrobenzo[a]xanthen-11-ones via three-component, one-pot condensation reaction of dimedone, β-naphthol, and aromatic aldehydes. An uncomplicated work-up, high yields of product, short reaction times, and use of low-cost catalyst are considerable advantages of this procedure. [ABSTRACT FROM AUTHOR]

This work aimed to produce novel heterocyclic compounds such as chromene, thieno[3,2-f]chromene, chromeno[5,6-d]thiazole and quinoline derivatives. The newly synthesized heterocyclic compounds were evaluated against cancer cell lines aiming to get new anticancer agents. Dimedone underwent different multi-component reactions to produce fused thiophene, thiazole, coumarin, pyran and pyridine derivatives. Some reactions were catalyzed by effective magnetically separable nanocatalyst. The anti-proliferative activity of the newly synthesized compounds toward six cancer cell was studied. In addition, inhibitions of the most active compounds the thieno[3,2-f]chromene derivatives 16a–f toward cancer cell lines classified according to the disease were also studied. Moreover, the newly synthesized compounds were screened for their anticancer potentials against hepatocellular carcinoma HepG2 and cervical carcinoma HeLa cell lines. Anti-proliferative evaluations, inhibitions were performed for all of the synthesized compounds where the varieties of substituent through the aryl ring and the heterocyclic ring afforded compounds with high activities. Inhibitions toward cancer cell lines classified according to the disease together with inhibitions toward HepG2 and cervical carcinoma HeLa cell lines were measured. Molecular docking of compounds 15c and 18c was performed. [ABSTRACT FROM AUTHOR]

Pseudo-multicomponent reactions (Pseudo-MCRs) have led to a variety of compounds with interesting biological properties, especially desirable in the pharmaceutical industry. The isatin nucleus could be considered a privileged scaffold for the design of biologically active substances. Dimedone is an interesting and versatile molecule for most organic transformations, especially one-pot and multicomponent reactions. Xanthene derivatives are still an attractive research field for both academia investigations and industry. In this investigation, a simple and efficient tandem Knoevenagel–Michael protocol with subsequent cyclization for the synthesis of the previously unknown 4a′-hydroxy-3′,3′,5,6′,6′,7-hexamethyl-3′,4′,4a′,6′,7′,9a′-hexahydrospiro[indole-3,9′-xanthene]-1′,2,8′(1H,2′H,5′H)-trione was elaborated. The suggested method is based on the pseudo-MCR of 5,7-dimethylisatin and dimedone. The structure of the earlier unknown compound was proven using 1H, 13C-NMR, and IR spectroscopy, mass spectrometry, and elemental analysis. To compare the developed protocol with the existing ones, unsubstituted spiro[indole-3,9′-xanthene] was synthesized. Its structure has been proven using two-dimensional (2D) NMR spectroscopy techniques. [ABSTRACT FROM AUTHOR]

Copper incorporated hydroxyapatite encapsulated Kit-6 (Cu@HAp@KIT-6) has been used as an effective nanocatalyst in the synthesis of 1,2,4-triazolo[5,1-b]quinazolin-8-one derivatives by a one-pot reaction of 3-amino-1,2,4-triazole, dimedone and aromatic aldehydes in ethanol. This novel protocol affords the products under optimized reaction conditions with high to excellent yields (88-97%) and lower reaction times (40-50 min). Wide substrate scope, facile work-up procedure, reduced reaction time, the use of green solvent and recyclability of the catalyst are some prominent advantages of this protocol. The catalytic activity of the catalyst after six consecutive runs has been preserved without an appreciable decrease in its activity. [ABSTRACT FROM AUTHOR]

Glutamic acid is used as an efficient organocatalyst for one-pot synthesis of tetrahydrobenzo [b]pyran via condensation of an aromatic aldehyde, dimedone and malononitrile in ethanol: water (1:4) as solvent at reflux temperature. The short reaction time, cleaner reaction, and easy workup make this protocol practical and economically attractive.

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glutamic acid is used as an efficient organocatalyst for one-pot synthesis of tetrahydrobenzo [b]pyran via condensation of an aromatic aldehyde, dimedone and malononitrile in ethanol: water (1:4) as solvent at reflux temperature. The short reaction time, cleaner reaction, and easy workup make this protocol practical and economically attractive. [ABSTRACT FROM AUTHOR]

The regioselective synthesis of a new series of pyrazolo[5,1‐b]quinazolines was carried out using a three‐component protocol. The protocol involved the reaction of the appropriate benzaldehydes, dimedone, and 1H‐pyrazole‐ 3,5‐diamine in DMF at 150 °C. Using a similar protocol, three additional series of bis(pyrazolo[5,1‐b]quinazolines), linked to different spacers, were prepared utilizing the respective bis(aldehydes). The new products showed a wide spectrum of antibacterial activity against six different the American Type Culture Collection (ATCC) bacterial strains. In general, p‐xylene‐linked bis(pyrazolo[5,1‐b]quinazolines) had good antibacterial activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values up to 8.3 and 16.6 μM, respectively. Additionally, (4‐nitrophenyl)‐linked pyrazolo[5,1‐b]quinazoline had the best antibacterial activity with MIC/MBC values up to 2.1/4.3 μM. The Salmonella typhimurium reverse mutation assay (Ames mutagenicity test) was used to conclude that the (4‐nitrophenyl)‐linked product was not mutagenic to the Salmonella strains. Both the drug‐likeness model score and the SwissADME predict the (4‐nitrophenyl)‐linked product's good physicochemical properties, and drug likeness. [ABSTRACT FROM AUTHOR]

In this study novel 2-(4-(1-phenyl-1H-pyrazol-3-yl)phenoxy)-N-arylacetamide hybrids with fused 1,4-dihydropyridines such as acridines and tetrahydrodipyrazolo[3,4-b:4',3'-e]pyridines were successfully and efficiently prepared through a one-pot multi-component reaction of 2-(4-(4-formyl-1-phenyl-1H-pyrazol-3-yl)phenoxy)-N-arylacetamide with dimedone, or 5-methyl-2,4-dihydro-3H-pyrazol-3-one at reflux. The tri-substituted methanes (TRSMs) were synthesized through the reaction of the appropriate aldehyde with 6-aminothiouracil and 4-hydroxycoumarin. The structures of novel compounds were confirmed based on spectral data. [ABSTRACT FROM AUTHOR]

An efficient and convenient method for synthesis of 7,10,11,12-tetrahydrobenzo[c]acridin-8(9H)-one derivatives using Cu/MCM-41 (20 mg) as heterogeneous catalyst. The advantages have an excellent product yield within a short time and easy work-up procedure, and the products have directly recrystallized from hot methanol with cost-effective catalyst. One-pot three-component reaction from aromatic aldehydes, cyclic 1,3-dicarbonyl compounds, and 1-naphthyl amine has been carried under ethanol as a solvent with reflux condition. Moreover, the catalyst can be recovered conveniently and reused efficiently, and recyclable. [ABSTRACT FROM AUTHOR]

A novel synthetic scheme has been designed for the synthesis of polyhydroquinoline derivatives via one-pot condensation of aromatic aldehydes, EAA, dimedone, and NH4OAc by employing synthesized STO as a heterogeneous solid acid catalyst in ethanol under reflux condition. FTIR, XRD, and SEM EDX were used to confirm the sulfated tin oxide. BET plots were used to analyze the surface area of the catalyst. The reactions were assessed for diverse solvents and catalyst loading. The yields of all the polyhydroquinoline derivatives were found to range between 80 to 92%. All the synthesized polyhydroquinolines were validated by spectral data. This exercise is efficient and green as it uses an environmentally friendly catalyst, has a significant atom economy, is cost-effective and easy to work up. [ABSTRACT FROM AUTHOR]

A convenient, rapid and electrochemical one‐pot protocol was developed successfully for the preparation of pyrazolo[3,4‐b]‐quinoline derivatives. The reaction is carried out in a 25 mL three neck flask equipped with graphite electrode as anode and iron electrode as cathode (electrode area of 1 cm2) with sodium bromide as supporting electrolyte at room temperature in ethanol. Fourteen pyrazolo‐[3,4‐b]‐quinoline derivatives were synthesized by use of various aldehyde (including aryl aldehydes and aliphatic aldehydes), dimedone and 5‐amino‐3‐methyl‐1‐phenylpyrazole as substrates in good yields (76–86 %) with a constant current of 30 mA after 0.14 F/mol of electricity passed. All aimed products were characterized by IR, 1H NMR and HRMS. Notably, the presented method features ecologically sound, simple experimental procedure and good yields. [ABSTRACT FROM AUTHOR]

A simple, efficient, and green, one-pot four-component synthesis of spiro[indoline-3,4′-quinoline] derivatives has been developed from isatin, ethyl cyanoacetate/malononitrile, dimedone, and aniline using green catalyst DABCO and green solvent ethanol. The current method generates good to exceptional yields in a short reaction time and provides a broad substrate scope. This method also works for gram-scale reactions. [ABSTRACT FROM AUTHOR]

In recent years, the application of privileged structures has become a powerful approach in the discovery of new biologically active molecules. Ion pairing is a strategy used to enhance the permeation of ionized topical drugs. A convenient and efficient method for the synthesis of triethylammonium 2-(3-hydroxy-2-oxoindolin-3-yl)-5,5-dimethyl-3-oxocyclohex-1-en-1-olate has been developed. The presented protocol includes an aldol reaction and the formation of an ammonium salt. Triethylamine is both a reactant and a catalyst in the process. The structure of the synthesized title compound has been established by 1H, 13C-NMR and IR spectroscopy, mass spectrometry, and elemental analysis. [ABSTRACT FROM AUTHOR]

A simple microwave assisted tungstophosphoric acid (H3PW12O40) catalyzed protocol was employed for the synthesis of versatile enaminoketones. The developed synthetic procedure is green, efficient and environmentally benign. Using this method, a series of enaminoketones were prepared from the condensation of dimedone and various amines. Further, the synthesized enaminoketones were evaluated for in-vitro anti-inflammatory activity by membrane stabilization method and anti-oxidant efficacy by radical scavenging method. The synthesized enaminoketones 3c, 3b and 3b, 3f showed reasonable anti-inflammatory as well as anti-oxidant activities respectively. [ABSTRACT FROM AUTHOR]

2-Amino-3-cyano-4H-pyran and -thiopyran derivatives were synthesized by three-component reac-tions of aldehydes, dimedone, and CH acids. The molecular and crystal structures of the synthesized compounds were determined by X-ray analysis. [ABSTRACT FROM AUTHOR]

The present paper describes the synthesis and characterization of the functionalized magnetite reduced graphene oxide (rGO@Fe3O4) with zirconocene dichloride as rGO@Fe3O4@ZrCp2Cl2. The prepared magnetic nanomaterial was characterized by Fourier‐transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), inductively coupled plasma optical emission spectroscopy (ICP‐OES) and mass spectrometry (MS). This new heterogeneous nanocatalyst showed the perfect catalytic activity towards synthesis of tetrahydrobenzo[b]pyran and Dihydropyrano[3,2‐c]chromenes derivatives through multicomponent reaction of dimedone or 4‐hydroxycoumarin, malononitrile and aromatic aldehydes in polyethylene glycol 400 (PEG‐400) at 100 °C. The influence of the amount of nanocatalyst, varying temperature of the reaction and the kind of solvent on the rate of condensation reaction was investigated. Recovery and reusability of the applied nanocatalyst was examined for five consecutive cycles without the significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

The present article involves preparation of some novel fused quinazoline analogs by employing aromatic aldehydes, 1,3-cyclic diketones (dimedone/cyclohexanedione) and urea/2-aminobenzothiazole, in catalytic amount of glycerol-based sulfonic acid. By employing glycerol-based sulfonic acid as a catalyst, the threat of metal contamination has been eradicated. The putative mechanism of this MCR strategy is similar to the Biginelli reaction involving Knoevenagel condensation followed by Michael addition. A series of fused derivatives confirmed the high functional group tolerance of the present protocol. The fabricated pathway has numerous advantages like high yields of desired products, green, solvent-free, and use of easily recoverable and reusable heterogeneous catalyst. Further, the anti-microbial results confirmed that among the synthesized compounds, compounds 4c and 6a were found more active as compared to ciprofloxacin against tested bacterial strains. Compounds 4g and 6a were found more active against tested fungal strains as compared to fluconazole. [ABSTRACT FROM AUTHOR]

In the fused ring system of the title compound, C24H27BrO5, the mean plane and maximum deviations of the central pyran ring are 0.0384 (2) and 0.0733 (2) Å, respectively. The cyclohexenone rings both adopt envelope conformations with the tetra-substituted C atoms as flap atoms, whereas the central pyran ring adopts a flattened boat conformation. The central pyran and phenyl substituent rings are almost perpendicular to each other, making a dihedral angle of 89.71 (2)°. In the crystal, pairs of molecules are linked via O—H...O hydrogen bonds, forming inversion dimers with an R22(20) ring motif. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H...H (50.6%), O...H/H...O (22.9%) and C...H/H...C (11.1%) contacts. Quantum chemical calculations for the frontier molecular orbitals were undertaken to determine the chemical reactivity of the title compound.

This work represents a simple and efficient synthesis of novel 2-amino-N'-(9H-fluoren-9-ylidene)-hexahydroquinoline-3-carbohydrazide derivatives via the multi-component reaction of diverse anilines, dimedone, 9-fluorenone, cyanoacetohydrazide, and aromatic aldehydes in the presence of piperidine as a catalyst. The proposed approach has some advantages as good yields, green medium, short reaction times, simple work-up, and purification process with no chromatographic technique compared with other methods. Supplemental data for this article is available online at at the publisher's website. [ABSTRACT FROM AUTHOR]

The experimental and theoretical studies of the reactions of 5,5-dimethylcyclohexane-1,3-dione (dimedone) with trimethyl- and triethyl orthoformates under various conditions were carried out. It was demonstrated that in the absence of activators the reactions of substrate with ortho esters proceed exclusively as C-C coupling, and in the presence of Brønsted (H2SO4) or Lewis (BF3·Et2O) acids the formation of both C-C and C-O coupling products is observed. The energy consumptions of all reactions in accordance with proposed mechanisms were estimated using quantum chemical calculations by the B3LYP/6-311++G(d,p) method in terms of PCM/MeCN. [ABSTRACT FROM AUTHOR]

Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds' adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced. [ABSTRACT FROM AUTHOR]

The present work highlights a rapid, efficient, eco-friendly protocol for synthesizing one-pot polyhydroquinolines via Hantzsch reaction and 2-amino-4H-chromene derivatives under catalyst-free condition. The present mild and greener method uses ethanol: water (1:1) without catalyst at R.T. and 90 °C. The structurally diverse substrates were selected to ascertain the ability of the current approach to handle different functional groups, including ketones as one of the substrates. The current methodology is economical and environmentally friendly for the three and four-component reaction of aliphatic, acyclic, aromatic, heterocyclic aldehydes in shorter reaction time, simple workup procedure, no catalyst with excellent yields, and high atom efficiency are the added advantages of this protocol. [ABSTRACT FROM AUTHOR]

A convenient, and multicomponent green procedure for the synthesis of triazolo[1,2-a]indazole-triones by the one-pot condensation reaction between 1,2,4-triazolidine-3,5-dione (urazole), 5,5-dimethylcyclohexane-1,3-dione (dimedone) and aldehydes in the presence of Origanum majorana-capped silver nanoparticles as a highly stable and reusable ecofriendly catalyst under solvent-free condition is described. Nanoparticle structure was analyzed using Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, transport electron microscopy (TEM) isotherm, and X-ray diffraction (XRD) spectra. This procedure provides several advantages such as simple, mild condition, easy workup, and excellent yield in a short time. All of the synthesized compounds were characterized by FT-IR, 1H NMR, 13C NMR, and elemental analysis. [ABSTRACT FROM AUTHOR]

An efficient green approach for the synthesis of 9-heteroaryl-acridine-1,8-dione derivatives (3a-f) was accomplished via reactions of dimedone (1) with various heteroaromatic aldehydes (2a-f) and ammonium acetate through one-pot multicomponent reactions in water under mild conditions using ultrasound irradiation in excellent yields. Of the synthesized compounds, 3d-f were novel and this process presents the advantages of high yields and easy work-up procedures. Spectral analyses were accomplished by FTIR, 1H NMR, 13C NMR and LC-MS TOF analyses.

A new magnetic supported manganese-based coordination complex (Fe3O4@SiO2@CPTMS@MBOL@ Mn) was prepared in consecutive stages and characterized via various techniques (VSM, SEM, TEM, XRD, FT-IR, EDX, TG-DTA, and ICP). To evaluate its application, it was used for synthesis of divers Indazolophthalazinetriones in a simple procedure via the one-pot three-component condensation reaction of aldehydes, dimedone, and phthalhydrazide in ethanol under reflux conditions. The Mn catalyst can be recycled without any noticeable loss in catalytic activity. Additionally, the antibacterial properties of the nano-catalyst were studied against some bacterial strains.

In this study, the domino Knoevenagel-Michael and cyclization reaction between 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and aryl aldehydes was performed in the presence of sulfacetamide as an organocatalyst in refluxing ethanol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxo-octahydroxanthene derivatives. This organocatalyzed reaction proceeds through the formation of 2,2′-[(4-(aryl)phenyl)methylene]bis[3-hydroxy-5,5-dimethylcyclohex-2-en-1-one] intermediates, leading to the construction of final oxygen-containing heterocyclic compounds. Considering the loading of the organocatalyst and the study of the effects of the solvent, it can be concluded that 2 mol% of catalyst and ethanol are the best choice to run the pseudo-three-component reaction. Furthermore, the pot-economy, atom-economy, and step-economy reaction follows some principles of green chemistry, such as cost-effectiveness, benign catalyst, and using nontoxic solvent. [ABSTRACT FROM AUTHOR]

In this work the multi-component reactions of either of the arylhydrazocyclohexan-1,3-dione derivatives 3a–c with either of benzaldehyde (4a), 4-chlorobenzaldehyde (4b) or 4-methoxybenzaldehyde (4c) and either malononitrile (5a) or ethyl cyanoacetate (5b) giving the 5,6,7,8-tetrahydro-4H-chromene derivatives 6a–r, respectively, are presented. The reaction of two equivalents of cyclohexan-1,3-dione with benzaldehyde gave the hexahydro-1H-xanthene-1,8(2H)-dione derivative 7. On the other hand, the multi-component reactions of compound 1 with dimedone and benzaldehyde gave 13. Both of 7 and 13 underwent heterocyclization reactions to produce fused thiophene, pyran and thiazole derivatives. Selected compounds among the synthesized compounds were tested against six cancer cell lines where most of them gave high inhibitions; especially compounds 3b, 3c, 6b, 6c, 6d, 6f, 6i, 6m, 6n, 8b, 14a, 15 and 16 being the most cytotoxic compounds. Further tests against the five tyrosine kinases c-Kit, Flt-3, VEGFR-2, EGFR, and PDGFR and Pim-1 kinase showed that compounds 3c, 6c, 6d, 6f, 6n, 14a and 15 were the most potent of the tested compounds toward the five tyrosine kinases and compounds 3c, 6c, 6d, 6n and 15 displayed the highest inhibitions toward Pim-1 kinase.

Cyclohexane‐1,3‐dione and its derivatives are imperative precursors in synthetic organic chemistry as they are useful intermediates for the synthesis of a wide range of biologically active natural products, heterocycles and pharmaceuticals. Recently, cyclohexane‐1,3‐diones have been used for the synthesis of varied array of six‐membered nitrogen‐containing heterocycles in the presence of aldehydes, acetoacetic esters, malononitrile, chalcones, coumarins, acetophenones, amino acids, amines, etc. under catalytic and non‐catalytic conditions. Newest studies on the importance of these heterocycles motivated us to compile all the recently developed processes which include the fabrication of six‐membered nitrogen heterocycles. This article is mainly focused on the efficient synthesis of six‐membered N‐heterocycles i. e. 1,4‐dihydropyridine, acridine‐1,8‐diones, benzoacridinones, quinolones and pyridine derivatives from cyclohexane‐1,3‐diones as one of the substrates, published for the last ten years. [ABSTRACT FROM AUTHOR]

An efficient green technique has been developed for the synthesis of some biologically active 12-aryl or 12-alkyl 8,9,10,12-tetrahydrobenzo[a]xanthenes-11-one and 3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione derivatives have been described. This process arranged a three-component one-pot condensation of aldehydes, 2-naphthol, and dimedone mediated by 2-aminophenol and has offered an excellent scope of tailoring a large number of xanthene derivatives with good to charming yields. Short reaction time, straightforward, easy product isolation technique, non-toxic catalyst, and above all metal-free process are noteworthy advantages of this method. [ABSTRACT FROM AUTHOR]

In this study, the synthesis and characterization of the modified GO and rGO@Fe3O4@Ni composite systems were investigated. Fourier‐transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy‐dispersive x‐ray spectroscopy (EDX), x‐ray powder diffraction (XRD), vibrating sample magnetometer (VSM), Brunauer–Emmett–Teller (BET) analysis, thermogravimetric analysis (TGA), and inductively coupled plasma optical emission spectroscopy (ICP‐OES) were employed to characterize the prepared nanomaterials. Also, catalytic activities of GO, rGO@Fe3O4, rGO@Ni, and rGO@Fe3O4@Ni were compared, and rGO@Fe3O4@Ni as the efficient magnetic nanocatalyst was applied to expedite the multicomponent coupling reactions (MCRs) of dimedone, malononitrile, and structurally diverse aromatic aldehydes to prepare tetrahydrobenzopyranes. All reactions were fulfilled efficiently in deionized water under reflux conditions. In addition, sustainability of the nanocatalyst was examined for five consecutive reaction cycles without the significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

The present paper shows that lanthanum(III) nitrate hexahydrate can be used as mild and environment friendly homogeneous catalyst for an efficient one-pot multi-component synthesis of biologically active 1,8-dioxo-octahydroxanthene and 14H-dibenzo[a,j]xanthene derivatives. The solvent free condensation reaction of aromatic aldehydes and dimedone or β-naphthol was carried out at 70-80ºC during 10-30 min. The advantages of this eco-friendly synthesis route are numerous, and include the use of an inexpensive catalyst, high to excellent yield, short reaction time and high catalytic activity that can make this method an interesting alternative to multi-step approaches.