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The aim of the present study was to evaluate the H2O2 scavenging activity of the ZnO2/β-CD as a biocompatible composite. Zinc peroxide was prepared via sonochemical approach. To synthesize a green composite, β-cyclodextrin was modified by citric acid (CA) and reacted with ZnO2 under ultrasonic irradiation. The prepared samples were characterized using XRD, SEM, TGA and FTIR analytical techniques. XRD analysis exhibited a typical pattern of ZnO2 and demonstrated the presence of citric acid and β-cyclodextrin in composite. The results of the catalytic assay showed that the ZnO2/CA-βCD composite displayed stronger capability to decompose H2O2 in comparison to ZnO2 particles (about seven times). It was attributed to increased adsorption capacity and solubility of composite due to the presence of citric acid and β-cyclodextrin. MTT assay studies confirmed the non-cytotoxic nature of ZnO2 particles and ZnO2/CA-βCD composite.

The three-component Hantzsch condensation of various aryl aldehydes, dimedone, and methyl 3-aminocrotonate was investigated in the presence of MCM-41-supported ZnNO3. The polyhydroquinoline products which were obtained under mild conditions and very easy workup were evaluated for anti-cancer activities against MCF-7, SK-BR-3, and HT-29 of breast and colon cancer cells. The fluorescence emission of some products was also studied and their optical parameters were reported.

The reaction of the free amine group in polyaryl-substituted imidazole structures with phenyl isocyanate or dimethyl acetylenedicarboxylate gave two new series of polyaryl-substituted imidazoles: biaryl ureas or vinyl esters, respectively. Besides their spectroscopic analysis, we explored the optical and electrochemical properties of these highly conjugated scaffolds. Comparing these properties in two categories of products yielded interesting results.

Reactions of 1,4,5-triaryl-2-(4-bromomethyl)phenyl-imidazoles with sodium azide in acetone give the corresponding azidomethyl derivatives, which on 1,3-dipolar cycloaddition with various terminal alkynes in the presence of CuI afford novel 1,2,3-triazole products. On the other hand, treatment of 2,4,5-triaryl-1-(4-hydroxyphenyl)-imidazoles with propargyl chloride in the presence of a base gives the corresponding propargyl ether derivatives, which under CuI-catalyzed 1,3-dipolar cycloaddition with benzyl azide produce 1,2,3-triazole derivatives. All the products are characterized from their spectroscopic data and most are evaluated for fluorescence emission. The optical parameters of the studied products are also reported.

Four polysaccharides (chitosan, cellulose, starch, and pectin) were magnetized with magnetic iron oxide (Fe3O4) and then sulfonated (except pectin) with chlorosulfonic acid. The obtained solid acids were used as a catalyst in three-component reactions between N-substituted-2-formylpyrrole, hydroxylamine-hydrochloride, and β-keto esters for the synthesis of 4-(2-pyrrolyl) methylene-isoxazole-5-ones. The optimal catalyst system was selected and studied by IR, SEM, TEM and XRD methods. The diverse isoxazoline derivatives (obtained via a mild and simple approach) were also fully characterized by spectroscopic methods and screened for anti-cancer activities against HT-29 and MCF-7 colon and breast cancer and HEK 293 normal cells. The results revealed interesting anti-cancer activities.

MCM-41 materials modified with Mg, Co, and Zn were prepared by direct synthesis method. The template-containing catalysts as bifunctional catalysts were evaluated for simultaneous esterification and transesterification reactions of waste cooking oil. All catalysts showed high FAME yield (≥92%) with methanol to oil mass ratio of 8:1, after 3 h. It was also found that [CTA]MCM-41 had a high catalytic activity achieving a maximum FAME yield of 93%. It might be because of the basicity and hydrophobicity induced by organic template. Furthermore, these catalysts can be reused without loss of catalytic activity due to the stability of organic template (CTA+) inside the pores.

A series of 4-(1-azolyl)aniline derivatives (azole = imidazole, benzimidazole, pyrazole, 3-methylpyrazole, and 4-methylpyrazole) underwent diazotization reaction by NaNO2/HCl. The diazonium salts were consequently treated with aromatics such as phenol, N,N-dimethylaniline, 2-naphthol, and 8-hydroxyquinoline to give the coupled azo compounds. The antibacterial activities of some of the products were evaluated against Gram-negative [Escherichia coli (ATCC 25922)] and Gram-positive [Staphylococcus aureus (ATCC 25923)] bacteria. Moreover, in vitro examinations for a series of the products corroborated anticancer activities against MCF7 breast cancer cells.

A cellulose based magnetic nanocomposite possessing NHC-Cu Complex has been synthesized and characterized. It was then applied as a highly active catalyst in one-pot three-component reaction of sulfonyl azides, secondary amines and triethylamine to afford N -sulfonylformamidines. Copper catalyzed oxidative transformation of C-N bond of triethylamine is a key step to give desired products. In contrast with the good reactivity of the conventional secondary amines, aromatic amines and NH containing heteroaromatics had no activity in these reactions. Moreover, the used nanocatalyst which could be recovered by external magnet, showed reasonable catalytic activity for several times.

The aim of the present study was to evaluate the H

This study reports the synthesis and characterization of a highly active catalyst based on chelated copper iodide on magnetic chitosan-salicylaldehyde Schiff base. This catalyst was successfully used for the three-component reaction of N-propargylphthalimide, tosylazide, and NH or OH containing nucleophiles to access new classes of N-sulfonylamidine or N-sulfonylimidate derivatives. The products, which were constructed via an in situ generated sulfonyl keteneimine intermediate, were obtained in good to excellent yields. Short reaction times, easy separation and reusability without significant loss of catalyst activity were found to be the notable features of this synthetic protocol.

Stilbene derivatives have been found to possess promising anticancer activities against human cancer cell lines in vitro. In the present study, we have investigated cytotoxic, apoptosis induction and DNA binding activity of new stilbene derivative, (E)-1-(4-Chlorophenyl)-4,5-diphenyl-2-[4-(4-methoxystryl)phenyl]-1H-imidazol (STIM) on K562 chronic myeloid leukemia cell line. Via MTT assay STIM demonstrated cytotoxic activity against K562 cell line with IC

In cancer therapy, biocompatible and smart nanocarriers are the most important types of therapeutic agents. In this paper, a novel magnetic nanocarrier was fabricated and investigated for controlled release of methotrexate (MTX). A magnetic nanocarrier was synthesized by decoration of Fe3O4 nanoparticles using biocompatible tris(2-aminoethyl)amine functionalized nanocrystalline cellulose (AMFC). AMFC coated magnetic nanoparticles (AMFC@MNPs) were characterized by various technologies including FTIR, SEM-EDX, VSM, XRD, DLS and zeta potential analysis. MTX was loaded on the nanocarrier at physiological pH (7.4) due to the hydrogen bonding and electrostatic interactions between cationic amino groups on the nanocarrier and anionic carboxylate groups of MTX molecules. The MTX release ability of the synthesized nanocarrier was proved through the comparison of in vitro drug release under simulated physiological and tumor tissue conditions. The cumulative release of the MTX-loaded nanocarrier was pH dependent with a superior release rate at pH 5.4. The results of MTT assay and DAPI staining showed that the MTX-loaded nanocarrier revealed a high cytotoxicity in the MCF7 breast cancer cell line after 48 h incubation. Also, the results of cytotoxicity and hemolysis assays have shown that there are negligible toxicity and hemolytic effects of AMFC@MNPs at high concentrations. Therefore, it was concluded that our nanocarrier has many promising advantages as an efficient carrier for the targeted MTX delivery to the cancer cells.

A series of 2-(4-styrylphenyl)-1,4,5-triaryl imidazole derivatives have been efficiently synthesized through Wittig reactions starting with 2-[(4-bromomethyl)phenyl]-1,4,5-triarylimidazoles and been verified by spectroscopic data. The optical absorption and emission properties of the synthesized novel (E)-stilbene derivatives were examined in dilute ethanol solution. Most of the products exhibit a strongly enhanced fluorescence intensity.

A series of novel 1,2,3-triazole derivatives containing kojic acid moiety were synthesized by 1,3-dipolar cycloaddition reaction of 2-(azidomethyl)-5-hydroxy-4H-pyran-4-one and 2-(azidomethyl)-5-benzyloxy-4H-pyran-4-one with different alkynes in 41–99% yields. In the case of terminal alkynes, the reactions occurred in the presence of Cu(I) catalyst. The antioxidant activity of the synthesized compounds containing 5-hydroxyl group was evaluated by 1,1-diphenyl-2-picrylhydrazyl method.

Chemotherapy as an important tool for cancer treatment faces many obstacles such as multidrug resistance and adverse toxic effects on healthy tissues. Drug delivery systems have opened a new window to overcome these problems. A polyelectrolyte carboxymethyl cellulose polymer as a magnetic nanocarrier was synthesized for enhancing delivery and uptake of doxorubicin in MCF7 breast cancer cells and decreasing the adverse toxic effects to healthy tissues. The physicochemical properties of developed nanocarrier showed that it can be used in drug delivery purposes. The efficiency of the delivery system was assessed by loading and release studies. Besides, biological assays including protein-particle interaction, hemolysis assay, cytotoxicity study, cellular uptake, and apoptosis analysis were performed. All results persuaded us to investigate the cytotoxic effects of nanocarrier in an animal model by determining the biochemical parameters attributed to organ injuries, and hematoxylin and eosin (H&E) staining for histopathological manifestations. We observed that the nanocarrier has no toxic effect on healthy tissues, while, it is capable of reducing the toxic side effects of doxorubicin by more cellular internalization. Chemical characterizations and biological studies confirmed that developed nanocarrier with permanent cationic groups of imidazolium and anionic carboxylic acid groups is an effective candidate for anticancer drug delivery.

Supplemental material, Supporting_information_PDF for Synthesis and optical properties of novel 1,2,3-triazole derivatives possessing highly substituted imidazoles by Zarrin Ghasemi, Arezoo Mirzaie, Roqhayeh Arabzadeh, Zahra Fathi and Ameneh Abolghassemi Fakhree in Journal of Chemical Research

Palladium-catalyzed cross-coupling reactions of 2,6-diaryl-3,5-dibromo-4-pyrones with imidazole and benzimidazole in the presence of N,N′-dibutylbenzimidazol-2-ylidene as ligand resulted in the formation of the monosubstituted C- and N-arylated products. Kojic acid was also treated with some aryl halides at the same conditions, to afford C-6 arylated derivatives.

A series of novel polyaromatic derivatives of imidazole were synthesized by Bi(III) nitrate-SiO$_{2}$ catalyzed four-component reactions of benzil, ammonium acetate, aromatic aldehydes, and $N$-heterocyclic derivatives of aniline under solvent-free conditions.

In this study, a highly active catalyst based on copper iodide nanoparticles supported on magnetic aminomethylpyridine functionalized cellulose has been synthesized and characterized. Its catalytic activity was investigated in the multicomponent synthesis of N-sulfonylamidines via an in situ generated sulfonyl ketenimine intermediate under solvent free conditions at room temperature. The desired products were obtained in good to excellent yields at short reaction times. Based on observed results, the synthesized catalyst was an efficient, magnetically separable, recyclable and green catalyst from a natural source.

The three component Biginelli condensation of various aryl aldehydes, 1,3-dicarbonyls and urea was investigated in the presence of free or MCM-41 supported ZnNO3. The pyrimidone products, which were obtained under solvent-free conditions, were evaluated for antibacterial and antifungal activities as well as their cytotoxicities.

The oxidation of Baylis-Hillman adducts, obtained by the reaction of 5-benzyloxy-2-formyl-4-pyrone, with o-iodoxybenzoic acid generates β-ketomethylene intermediates that in situ undergo conjugative attack of NH-containing heterocycles such as imidazole and pyrazoles.

Two approaches for metal ion incorporation were employed to introduce Zn into MCM-41; Direct Synthesis (DS) and Wet Impregnation (WI). The ionic template was removed by two different methods: calcination and solvent extraction. For comparison, a series of template-containing mesoporous Zn/MCM-41 was also synthesized without surfactant removal. The catalysts were examined in a three component reaction to afford benzoxanthene derivative. The templae-containing Zn/MCM-41 showed particularly the highest activity. This activity is due to both Lewis acid sites and the ionic template. This catalyst could be reused without loss of its catalytic activity because the organic template does not leach during the reaction. It is also very efficient for the synthesis of a hydroxanthene derivative.

A novel heterogeneous nanocatalyst was fabricated by depositing copper iodide and Fe3O4 nanoparticles on imidazolium-based ionic liquid-grafted cellulose and successfully characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and flame atomic absorption spectrometry. It was employed to catalyse the reaction of terminal acetylenes with sulfonyl azides to afford highly reactive sulfonyl ketenimine intermediates which were subsequently trapped by secondary amines to give N-sulfonylamidines and N-sulfonylacrylamidines under solvent-free conditions at room temperature. Good to excellent yields, very short reaction times, eco-friendly processing, easy separation and reusability without significant loss of catalytic activity were found to be the notable features of this synthetic protocol.

A series of kojic acid benzyl ether derivatives possesing imidazole, benzimidazole, and pyrazole rings were synthesized by SN2'-substitution of these heterocycles using prepared Baylis–Hillman acetates.

Palladium-catalyzed cross-coupling reactions of 2,6-diaryl-3,5-dibromo-4-pyrones with imidazole and benzimidazole in the presence of N,N′-dibutylbenzimidazol-2-ylidene as ligand resulted in the formation of the monosubstituted C- and N-arylated products. Kojic acid was also treated with some aryl halides at the same conditions, to afford C-6 arylated derivatives.

The three component Biginelli condensation of various aryl aldehydes, 1,3-dicarbonyls and urea was investigated in the presence of free or MCM-41 supported ZnNO3. The pyrimidone products, which were obtained under solvent-free conditions, were evaluated for antibacterial and antifungal activities as well as their cytotoxicities.

A series of mono- and bis-benzimidazolium and imidazolium salts of 4-pyrone derivatives has been synthe- sized in good yields, by various quaternization reactions of halomethyl derivatives of 4H-pyran-4-ones. These salts can be used as novel precursors of functionalized N-heterocyclic carbenes and some of them as novel ionic liquids.

Nucleophilic substitution reactions of N -heterocycles such as imidazole, benzimidazole, indole and pyrazole as well as NH2 or OH containing heterocycles, with electron-deficient aryl halides in the presence of t-BuOK or K2CO3 as base and DMSO as solvent are reported. A series of N -aryl azoles, unsymmetric diaryl ethers and diaryl amines were obtained in good yields.

A series of fused pyrimidone derivatives of 4-pyrones was synthesized by conversion of the acetates of Baylis−Hillman adducts obtained from 2-formyl-4-pyrones with 2-aminopyridine and 2-aminothiazole.

A series of mono- and bis-benzimidazolium and imidazolium salts of 4-pyrone derivatives has been synthe- sized in good yields, by various quaternization reactions of halomethyl derivatives of 4H-pyran-4-ones. These salts can be used as novel precursors of functionalized N-heterocyclic carbenes and some of them as novel ionic liquids.

Title compounds (VII) and (IX) are synthesized starting by Baylis—Hillman reaction of formylpyrones (I) under convenient conditions.

2,6-Bis(1H-indole-6-yl)-4H-pyran-4-one was synthesized via Leimgruber–Batcho methodology starting from 2,6-bis(4-methyl-3-nitrophenyl)-4H-pyran-4-one . Enamine intermediate in this reaction, , reacts with aroyl chlorides in the presence of 1,4-diazabicyclo[2.2.2]octane in dioxane to give the substituted enamines . Enamines undergo reductive cyclization with Fe/AcOH to the corresponding 3-aroylindoles 10a ,10b. J. Heterocyclic Chem., 46, 273 (2009).