Synthesis, biological evaluation and in silico study of 4-(benzo[d]thiazole-2-yl) phenols based on 4-hydroxy coumarin as acetylcholinesterase inhibitors.

Alzheimer's disease, characterized by cognitive decline and memory loss, is associated with decreased acetylcholine levels due to acetylcholinesterase (AChE) activity. Compounds containing a coumarin heterocyclic core coupled with thiazole exhibit excellent acetylcholinesterase inhibitory activity. In this work, we designed and synthesized a series of 4-(benzo[d]thiazole-2-yl) phenols based on 4-hydroxycoumarin.

Carbon nanofiber/taurine-catalyzed synthesis of coumarin and 1,2,4,5-tetra-substituted imidazole derivatives under metal-free conditions.

The main subject of this research is the development of a suitable, efficient, and biocompatible carbon nanofiber-based catalytic system for the synthesis of coumarin and 1,2,4,5-tetra-substituted imidazoles. Brønsted acid carbon nanofiber/taurine catalyst was made during three steps: acid treatment, acylation, and then amination. The basic principles and general advantages of the synthesis method are elaborated.

Sb(iii)/Gum Arabic composite as a new natural-based environmentally green catalyst for the one-pot pseudo-four-component synthesis of 2-indazolo[2,1-] phthalazinetriones.

Sb(iii)-Gum Arabic composite as a unique natural-based and nontoxic catalyst was synthesized and characterized by FT-IR, XRD, TGA, ICP, BET, EDX and mapping. A four-component reaction of phthalic anhydride, hydrazinium hydroxide, aldehyde, and dimedone has been carried out in the presence of Sb(iii)/Gum Arabic composite to synthesise 2-indazolo[2,1-] phthalazine triones. The advantages of the present protocol are the appropriate reaction times, eco-friendly nature and high yields.

Synthesis of bis-spiro piperidines using nano γ-alumina supported Sb(v) under ultrasonic irradiation at room temperature conditions.

Group VA metalloid ion Lewis acids, Sb(v) was identified as a highly potent catalyst for the one-pot three-component synthesis of bis-spiro piperidine derivatives. The reaction was performed using amines, formaldehyde, and dimedone under ultrasonic irradiation at room temperature. The strong acidic property of the nano γ-alumina supported antimony(v) chloride plays a key role in accelerating the rate of the reaction and initiates the reaction smoothly.

FeO@nano-almond shell@OSi(CH)/DABCO: a novel magnetic nanocatalyst for the synthesis of chromenes.

In this work, we report the synthesis and characterization of FeO@nano-almond shell@OSi(CH)/DABCO as a novel magnetic natural-based basic nanocatalyst. The characterization of this catalyst was achieved using different spectroscopy and microscopy techniques, such as Fourier-transform infrared spectroscopy, X-ray diffractometry, field-emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy and mapping, vibrating-sample magnetometry, Brunauer-Emmett-Teller measurements, and thermogravimetric analysis. This catalyst was used for the one-pot synthesis of 2-amino-4-benzo[]chromenes-3-carbonitrile from the multicomponent reaction of aldehyde and malononitrile with α-naphthol or β-naphthol under solvent-free conditions at 90 °C.

FeO@nano-almondshell/Si(CH)/2-(1-piperazinyl)ethylamine as an effective magnetite almond shell-based nanocatalyst for the synthesis of dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyran derivatives.

The preparation and design of nano-catalysts based on magnetic biopolymers as green and biocompatible nano-catalysts have made many advances. This paper deals with the preparation of magnetite biopolymer-based Brønsted base nano-catalyst from a nano-almond (Prunus dulcis) shell. This magnetite biopolymer-based nano-catalyst was obtained through a simple process based on the core-shelling of nano-almond shell and FeO NPs and then the immobilization of 3-chloropropyltrimethoxysilane as linker and 2-aminoethylpiperazine as a basic section.

A green protocol ball milling synthesis of dihydropyrano[2,3-c]pyrazole using nano-silica/aminoethylpiperazine as a metal-free catalyst.

Background: Ball mill is an effective, and green method for the synthesis of heterocyclic compounds in very good yields. This method is a simple, economical, and environmentally friendly process. In this work, an efficient approach for the synthesis of pyranopyrazoles (PPzs) using ball milling and metal-free nano-catalyst (Nano-silica/aminoethylpiperazine), under solvent-free conditions was reported.

One-pot synthesis of chromenes in the presence of nano-cellulose/Ti/FeO as natural-based magnetic nano-catalysts under solvent free conditions.

In this study, the preparation of magnetic catalysts of titanium tetrachloride stabilized on nano-cellulose named cellulose/Ti/FeO was investigated. Various methods such as XRD, SEM, FT-IR, BET, EDX, TEM, TGA and VSM were used to characterize the catalysts. Then, the identified catalysts were used for the synthesis of various chromene skeletons reaction of malononitrile, aldehyde and dimedone, 4-hydroxycoumarine or 2-naphthole at 70 °C under solvent free conditions.

One-pot synthesis of naphtho[1,2-e][1,3]oxazines in the presence of FNAOSiPAMP*/Cu as an almond shell based nanocatalyst.

In the present research work, a novel catalyst based on natural material, namely, FeO@nano-almondshell@OSi(CH)/NHCHpyridine/Cu abbreviated (FNAOSiPAMP/Cu) was designed and prepared. The properties of the catalyst was identified by Fourier-transform infrared spectroscopy (FT-IR), Thermogravimetry ananlysis (TG), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), and Mapping. Furthermore, the evaluation of catalytic activity was done in the course of naphtho-1,3-oxazines synthesis.

Preparation and application of FNAOSiPPEA/Cu(II) as a novel magnetite almondshell based Lewis acid-Bronsted base nano-catalyst for the synthesis of pyrimidobenzothiazoles.

Background: The magnetic nano-catalysts improve the contact between substrates and catalyst considerably and simple isolation of catalyst from reaction mixture. In this study, FeO@nano-almondshell@OSi(CH)/2-(1-piperazinyl)ethylamine/Cu(II) abbreviated (FNAOSiPPEA/Cu(II)), was prepared, characterized and applied for the synthesis of 4H-pyrimido[2,1-b]benzothiazole.

Results: FNAOSiPPEA/Cu(II) as a bio-based nano-catalyst was prepared from the complexation of copper on 2-(1-piperazinyl)ethylamine, which was immobilized on FeO@nano-almondshell@OSi(CH) section.

Catalyst-free synthesis of tetrahydrodipyrazolopyridines via an one-pot tandem and green pseudo-six-component reaction in water.

Background: A new, green and environmentally friendly protocol has been developed for the synthesis of tetrahydrodipyrazolopyridine derivatives. The structures of these products were determined in terms of melting point, FTIR, NMR and Mass spectroscopy.

Results: The tetrahydrodipyrazolopyridine derivatives were synthesized in water through a catalyst-free pseudo-six-component reaction of hydrazine hydrate, ethyl acetoacetate, ammonium acetate and aldehyde at room temperature.

Nano-SiO/DBN: an efficacious and reusable catalyst for one-pot synthesis of tetrahydrobenzo[b]pyran derivatives.

Background: The nano-sized particles enhance the exposed surface area of the active part of the catalyst, thereby increasing the contact between precursors and catalyst considerably. In this study, nano-SiO/1,5-diazabicyclo[4.3.

Cancer Treatment by Caryophyllaceae-Type Cyclopeptides.

Cancer is one of the leading diseases, which, in the most cases, ends with death and, thus, continues to be a major concern in human beings worldwide. The conventional anticancer agents used in the clinic often face resistance among many cancer diseases. Moreover, heavy financial costs preclude patients from continuing treatment.

Rapid four-component synthesis of dihydropyrano[2,3-c]pyrazoles using nano-eggshell/Ti(IV) as a highly compatible natural based catalyst.

Nano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions.

Gum arabic-OPOH as a new natural-based green catalyst for the one-pot pseudo-four-component synthesis of naphtho[1,2-][1,3]oxazines.

Gum arabic-OPOH (GA-OPOH) as a unique natural-based green catalyst was synthesized by the reaction of phosphorus pentoxide with gum arabic. The structure and properties of the catalyst were studied several analysis methods such as FT-IR, MAPPING, EDS, SEM, XRD, and TGA. The efficiency of the above-mentioned catalyst was investigated for the synthesis of naphtho-1,3-oxazines a pseudo-four-component reaction of primary amines, formaldehyde, and 2-naphthol under the solvent-free grinding condition at room temperature using an electrical mortar-heater.

Docking, Synthesis and Evaluation of the Antifungal Activity of Pyrimido [4,5-b]quinolins.

In order to expand the application of FeO@SiO-SnCl in the synthesis of heterocyclic compounds, in this study, we wish to report the use of one-pot three component synthesis of pyrimido [4,5-]quinolone derivatives ( ) through reaction of 6-amino-2-(methylthio)pyrimidin-4 (3)-one, dimedone, or 1,3-cyclohexadione and aldehydes in the presence of FeO@SiO-SnCl as an efficient eco-friendly catalyst under ultrasound irradiation. The final aim of this study is evaluation of antifungal activity of resulted products. Synthesis of pyrimido [4,5-]quinolin derivatives were done three components coupling reaction of aldehyde, dimedone or 1,3-cyclohexadione and 6-amino-2-(methylthio)pyrimidin-4 (3)-one in the presence of FeO@SiO-SnCl under ultrasonic irradiation in water at 60 °C.

Nano-FeO@walnut shell/Cu(ii) as a highly effective environmentally friendly catalyst for the one-pot three-component synthesis of 1,3-oxazine derivatives under solvent-free conditions.

FeO@walnut shell/Cu(ii) as an eco-friendly bio-based magnetic nano-catalyst was prepared by adding CuCl to FeO@walnut shell in alkaline medium. A series of 2-aryl/alkyl-2,3-dihydro-1-naphtho[1,2-][1,3]oxazines were synthesized by the one-pot three-component reaction of β-naphthol, formaldehyde and various amines using nano-FeO@walnut shell/Cu(ii) at 60 °C under solvent-free conditions. The catalyst was removed from the reaction mixture by an external magnet and was reusable several times without any considerable loss of its activity.

Nano-SnCl.SiO, an efficient catalyst for synthesis of benzimidazole drivatives as antifungal and cytotoxic agents.

The concept of green chemistry has made significant impact on many frontages including the use of green solvents or sustainable catalyst materials. Benzimidazole ring is an important nitrogen-containing heterocyclic, which exhibits a broad spectrum of bioactivities and are widely utilized by the medicinal chemists for drug discovery. A simple and efficient method was developed for the synthesis of some benzimidazole derivatives reaction of -phenylenediamine and substituted aldehydes in the presence of nano-SnCl/SiO as a mild catalyst.

Structure-activity relationship studies of Longicalcynin A analogues, as anticancer cyclopeptides.

Cancer has emerged as the main cause of the highest rate of mortality in the world. Drugs used in cancer, although, show some beneficial effects on cancerous organs, demonstrate side effects on other normal tissues. On the other hand, anticancer peptides, being effective on target tissues, should be safe and less harmful on healthy organs, since peptides have several advantages, i.

Nano-kaolin/Ti/FeO: a magnetic reusable nano-catalyst for the synthesis of pyrimido[2,1-]benzothiazoles.

Herein, nano-kaolin/Ti/FeO as a new magnetic nano-catalyst was synthesized, and its structural properties were characterized using various techniques such as Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), a vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA) and energy-dispersive X-ray spectroscopy (EDX). This catalyst was used for the synthesis of pyrimido[2,1-]benzothiazoles the one-pot condensation of 2-aminobenzothiazole, an aldehyde and β-keto ester under solvent-free conditions at 100 °C. This simple protocol has many advantages such as easy workup, high product yields, short reaction times and reusability of the catalyst.

Synthesis and biological evaluation of new N-benzylpyridinium-based benzoheterocycles as potential anti-Alzheimer's agents.

A novel series of benzylpyridinium-based benzoheterocycles (benzimidazole, benzoxazole or benzothiazole) were designed as potent acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors. The title compounds 4a-q were conveniently synthesized via condensation reaction of 1,2-phenylenediamine, 2-aminophenol or 2-aminothiophenol with pyridin-4-carbalehyde, followed by N-benzylation using various benzyl halides. The results of in vitro biological assays revealed that most of them, especially 4c and 4g, had potent anticholinesterase activity comparable or more potent than reference drug, donepezil.

One-pot solvent-free synthesis of 2,3-dihydro-2-substituted-1H-naphtho[1,2-e][1,3]oxazine derivatives using FeO@nano-cellulose/TiCl as a bio-based and recyclable magnetic nano-catalyst.

The present study describes an efficient and environmentally benign protocol for the synthesis of 2,3-dihydro-2-substituted-1H-naphtho[1,2-e][1,3]oxazine derivatives. Synthesis is done by one-pot three-component condensation of 2-naphthol, formaldehyde, and primary amines in the presence of FeO@nano-cellulose/TiCl as a bio-based magnetic nano-catalyst under solvent-free conditions at room temperature grinding. This green procedure offers the advantages of high yield, short reaction time, environmental friendliness, easy workup, simple magnetic recovery of the catalyst and its reusability up to ten times without significant loss of catalytic activity.

Synthesis of Linear and Cyclic Disulfide Heptapeptides of Longicalycinin A and Evaluation of Toxicity on Cancerous Cells HepG2 and HT-29.

In this work, linear and cyclic disulfide heptapeptides of Longicalycinin A have been successfully synthesized by solid phase methodology with Fmoc /t-Bu and solution phase, respectively. 2-Chlorotrityl chloride resin (2-CTC) was used as a solid support. The synthesized linear disulfide analogue of Longicalycinin A was cleaved from the resin as a protected peptide.