Preparation, characterization and use of new lignocellulose-based bio nanocomposite as a heterogeneous catalyst for sustainable synthesis of pyrimido benzazoles

<p>A sustainable combinatorial synthesis of densely substituted pyrimido [1,2-b] benzazole derivatives in water under microwave irradiation was performed using a new lignocellulose-based bio nanocomposite (BNC) as heterogeneous catalyst. The lignocellulosic waste peanut shells (LCWPS) were turned into a value-added product, a new BNC PS/ZnO, which was prepared <i>via in situ</i> hydrothermal synthesis. The as-prepared BNC was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction spectrum. PS/ZnO has been successfully used in a sustainable catalytic method for the synthesis of pyrimido [1, 2-b] benzazole derivatives in water under microwave irradiation. The time of this reaction was significantly reduced. This catalytic system has a very high turnover number (TON ∼ 10³) and turnover frequency (TOF ∼ 10⁵h⁻¹). This paper presents the benefit of sustainable management of LCWPS, a bio-sourced polymeric carbohydrate for production of new nanocatalyst.</p

Organocatalytic clean synthesis of densely functionalized 4<i>H</i>-pyrans by bifunctional tetraethylammonium 2-(carbamoyl)benzoate using ball milling technique under mild conditions

<p>A green and simple method has been developed for efficient preparation of diverse annulated 2-amino-3-cyano-4<i>H</i>-pyran derivatives in the presence of a low loading of tetraethylammonium 2-(carbamoyl)benzoate (TEACB), as a bifunctional organocatalyst, under solvent-free conditions using the ball milling technique. This procedure is a clean, transition-metal-free, and environmentally friendly approach that offers many advantages including short reaction times, high to quantitative yields, low cost, and straightforward work-up.</p

MOESM1 of An improved solvent-free synthesis of flunixin and 2-(arylamino) nicotinic acid derivatives using boric acid as catalyst

Additional file 1. Supporting Information

Ultrasonic-Assisted Preparation, Characterization, and Use of Novel Biocompatible Core/Shell Fe₃O₄@GA@Isinglass in the Synthesis of 1,4-Dihydropyridine and 4<i>H</i>‑Pyran Derivatives

This work focussed on the synthesis of a new catalytic material isinglass (IG)-based Fe₃O₄@GA@IG core/shell magnetic nanoparticles and the investigation of its catalytic activity in two important multicomponent reactions. Fe₃O₄ nanoparticles were prepared using a simple coprecipitation method and then coated with IG consisting predominantly of the protein collagen in the presence of glutaraldehyde as a cross-linking agent. The obtained hybrid material has been characterized by Fourier transform infrared analysis, scanning electron microscopy, transmission electron microscopy (TEM), vibrating sample magnetometry, energy-dispersive X-ray, X-ray diffraction (XRD), and Brunauer–Emmett–Teller analyses. The results of XRD analysis implied that the prepared nanocomposite consists of two compounds of crystalline magnetite and amorphous IG, and the formation of its core/shell structure had been confirmed by TEM images. The catalytic performance of the as-prepared core/shell bionanocatalyst was evaluated for the first time in the synthesis of 1,4-dihydropyridine and 4<i>H</i>-pyran derivatives under sonication in ethanol. This core/shell structure because of the superparamagnetic property of Fe₃O₄ and unique properties of IG as a bifunctional biocatalyst offers a high potential for many catalytic applications. Recycling study revealed that no significant decrease in the catalytic activity was observed even after six runs

Synthesis, Molecular Docking, Molecular Dynamics Studies, and Biological Evaluation of 4<i>H</i>‑Chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylate Derivatives as Potential Antileukemic Agents

A series of 4<i>H</i>-chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylates derivatives were synthesized via a three component one-pot condensation of chromone-3-carbaldehyde, alkyl acetoacetate, and urea or thiourea, using MCM-41-SO₃H as efficient nanocatalysts and evaluated for their anticancer activity using a combined in silico docking and molecular dynamics protocol to estimate the binding affinity of the title compounds with the Bcr-Abl oncogene. Two programs, AutoDock 4 and AutoDock Vina software were applied to dock the target protein with synthesized compounds and ATP. AutoDock runs resulted in binding energy scores from −7.8 to −10.16 kcal/mol for AutoDock 4 and −6.9 to −8.5 (kcal/mol) for AutoDock Vina. Furthermore, molecular dynamics (MD) simulations are performed using Gromacs for up to 20 ns simulation time investigating the stability of a ligand–protein complex. Finally, a theoretical experiment using MD simulation for 10 ns was performed without defining the initial coordinates, and the affinity binding of ligand to receptors was directly studied, which revealed that the ligand approaches the active sites. The relative free binding energy for the structure 06 (<b>S06</b>), which has the highest binding energy in Autodock 4 and Autodock Vina (−10.10 and −8.5 kcal/mol, respectively), was also evaluated by molecular mechanics (MM) with Poisson–Boltzmann (PB) and a surface area solvation (MM-PBSA) method using g_mmpbsa tools for the last 15 ns MD. On the basis of binding energy scores, a negative binding energy value of 73.6 kcal/mol, <b>S06</b>, was recognized as the dominant potential inhibitors. The cytotoxic properties of <b>S06</b> was evaluated against three cell lines, acute T cell leukemia (Jurkat), human chronic myelogenous leukemia, (K562) and human foreskin fibroblast (Hu02) using the microculture tetrazolium test MTT assay. Cisplatin was used as the reference agent. The results indicated that <b>S06</b> has a higher safety index (SI = 0.73, IC50 = 152.64 μg/mL for Jurkat and IC50 = 110.25 μg/mL for Hu02, <i>P</i> < 0.05 means ± SD for four independent experiments) compared to cisplatin (SI = 0.56, IC50 = 8.86 μg/mL for Jurkat and IC50 = 4.96 μg/mL for Hu02). The <i>in silico</i> results indicated that the proposed structures, which have no toxic effects, are potential tyrosine kinase inhibitors (TKIs) that target Bcr-Abl and thus prevent uncontrolled cell growth (proliferation) but not necessarily cell death (apoptosis) and might potentially constitute an interesting novel class of targeted antileukemic drugs, which deserve further studies