Journal of the Iranian Chemical Society最新文献

By considering the importance of heterogeneous catalysts with separation and recycling ability from the reaction environment and ring opening of epoxide as a regularly essential conversion in organic synthesis, tetraaza macrocyclic complexes of Cu(П), Fe(IП) and Cr(Ш) were grafted on the acylated multiwalled carbon nanotubes (MWCNTs) to produce new nanocomposites as heterogeneous catalysts. Then the nanocomposites were applied in the regioselective ring-opening reaction of epoxystyrene with different alcohols to obtain β-alkoxy compounds. For the characterization of tetraazamacrocycle and nanocomposites, FT-IR, TGA, XRD, FE-SEM and Raman were employed. Results showed that the complexes were successfully grafted on the functionalized MWCNTs. Ring-opening reactions took place at high yield and favorite time, especially for the shorter chain alcohols. In the best case, nanocomposite containing Fe(Ш) (MWCNTs-C (=O)–TAM·Fe^III) accomplished the ring opening of epoxystyrene by methanol (100%) within 15 min at 50 °C, and after 3 recycling test, there are negligible changes in its catalytic performance.

Until now, there have been many reports on the regulation of inorganic metal ions on the catalytic activity of nanozymes, but few reports on the regulation of anions (such as NO₂⁻) on enzyme activity. In this work, a copper-molybdenum doped carbon dots (Cu, Mo-CDs) with peroxidase-like (POD) activity was synthesized by simple one-step microwave digestion method. The Cu, Mo-CDs + NO₂⁻ system can promote 3,3′,5,5′-tetramethylbenzidine (TMB) oxidizing to blue oxidative product (oxTMB) due to the formation of ∙NO₂ free radical. While Hg²⁺ was introduced into the system, the POD-like activity of Cu, Mo-CDs + NO₂⁻ system was inhibited due to the strong interaction and the electron transfer between Cu, Mo-CDs and Hg²⁺. The formation of ∙NO₂ and the electron transfer capability of Cu, Mo-CDs + Hg²⁺ were confirmed through ESR spectra and FMN experiments. The bioenzyme-free colorimetric assay based on Cu, Mo-CDs nanozyme is used for detection of NO₂⁻ and Hg²⁺, showing lower detection limit (LOD) of 1.63 µg/L for NO₂⁻, 0.13 µg/L for Hg²⁺, respectively and good recovery from 90.79 to 108.90%. The work paves a new way to design a nanozyme-based colorimetric protocol for traces NO₂⁻ and Hg²⁺ residues in food analysis.

A novel 2-(2,3,4-trimethoxyphenyl)-1H-phenanthro[9,10-d]imidazole crystal has been reported and characterized by FT-IR, ¹H NMR, and ¹³C NMR spectral techniques. Single-crystal XRD studies reveal that the compound crystallizes into orthorhombic crystal system with Pbcn space group, and crystallographic data have been deposited in the Cambridge crystallographic data centre with CCDC number: 2244532. Various computational analyses such as hydrogen bond analysis, molecular electrostatic potential analysis, natural population analysis, Hirshfeld surface, and Frontier molecular orbital analysis were performed to elucidate the structure of the crystal. The calculation of reorganization energy and coupling constant using DFT methods reveals that the compound could be investigated as a hole transport material.

In recent years, “sulfate-free” products have become increasingly common for most cosmetics and personal care products. With a boom in the number of sulfate-free claims, an analytical method for determining sulfate is certainly needed. Analysis of sulfate in cosmetic products can be difficult due to matrix interference and the complex nature of the ingredients used in the formulation. A simple and novel modified method for the determination of sulfate was developed by using UV–Vis spectroscopy. The procedure involved the precipitation of sulfate as barium sulfate and the removal of interference under controlled conditions, using different reagents such as acid, glycerol and ethanol. The method was optimized for the best conditions using response surface methodology. According to the experimental design, nitric acid and glycerol at 2% concentration yielded the maximum absorbance and the optimized method was validated in terms of linearity, accuracy, precision, limit of detection and limit of quantification. Fifteen market samples belonging to the shampoo and conditioner product types were analyzed to evaluate the performance of the optimized method. The results obtained were found to be satisfactory, and the proposed method is linear (R²—0.9971), accurate (89 to 92%), precise (%RSD < 4) and robust (% deviation < 5) with limit of detection (4.2 mg/l), limit of quantification (12.59 mg/l) and can be employed for the analysis of sulfate in cosmetics and personal care products.

Vitamins are not only essential for normal cell function but also important in organic transformations, specifically in the field of organocatalysis. Due to the increasing importance of sustainable and ecofriendly organic reaction protocols, there has been growing attention in organocatalysis owing to easy access, biocompatibility, and excellent reactivity. As vitamins are environmentally benign, nontoxic, and economic organocatalyst, VB₁, VB₂, and VB₁₂ have been employed successfully in variety of organic transformations. The catalysts exhibited very high efficacy in various C–C bond-forming reactions from multicomponent reaction to cross-coupling reactions. This review concisely demonstrates catalytic performance of natural organocatalyst VB₁, VB₂, and VB₁₂ and also provides basic knowledge about this important synthetic tool for the preparation of organic compounds in a greener manner. The review explores the versatile application of vitamins where vitamins acted as the principal catalyst (Lewis acidic catalyst, photocatalyst), co-catalyst, organometallic catalyst, and ligand of metal ion catalysts. Utilization of vitamin-functionalized nanocatalysts in cross-coupling, A³-coupling, oxidation reaction, etc. has been demonstrated thoroughly. Additionally, the mechanistic details illuminating the roles of vitamins in important organic transformations are meticulously explained, providing insights into reaction pathways and empowering the described organcatalysis approaches.

In the present study, a modified carbon nano-onion and β–cyclodextrin composite was utilized in micro-solid phase extraction of atenolol and metoprolol from human plasma samples. The synthesized sorbent structure and morphology were evaluated. In this method, a proper amount of the sorbent was contacted with the diluted plasma sample under vortexing (to promote the sorbent contact area with the solution). The separated particles by centrifugation were contacted with a proper eluent to desorb the target analytes. After that, the eluent was separated by centrifugation and used during analysis of the analytes by high-performance liquid chromatograph. Several effective extraction parameters such as the sorbent amount, type and elution solvent volume, and extraction time were evaluated and optimized. The validated factors showed that detection and quantification were 0.09 and 0.01 and 0.29 and 0.03 ng mL^–1, for metoprolol and atenolol, respectively. The method precision, considered as relative standard deviation, was ≤ 2.5 and ≤ 3.6% for intra- (n = 5) and inter-day (n = 4) precisions, respectively. The extraction recovery values were obtained 84 and 63% for metoprolol and atenolol, respectively. Lastly, the developed method was utilized successfully on the plasma samples of patients treated with metoprolol and atenolol.

In this study, β-diketone derivative new carboxamide Eu(III) and Tb(III) lanthanide complexes were synthesized and characterized by FT-IR, elemental analysis, UV–Vis, and molar conductivity techniques. There is no electrolytic conductivity in the compounds. Moreover, the photoluminescence properties and thermal behavior of the synthesized lanthanide complexes were investigated. Photoluminescence data revealed that the Tb(III) complex showed metal-based f-f transitions. The β-diketone derivative carboxamide ligand exhibited as antenna that transmitted the excited energy to the emission energy levels of the Tb(III) ion. These metal complexes were screened in two different common cancer cell lines and a human normal embryonic kidney cell line for 48 h. The results showed that these complexes have more antiproliferative activities in the colon cancer cell line compared to the lung cancer cell line.

In order to improve the activity of copper (Cu) towards electrolytic reduction of nitrate, thin films of magnesium hydroxide (Mg(OH)₂) were deposited on Cu substrate. For the first time, these films were synthesized by electrochemical deposition in a potassium sulfate bath containing Mg²⁺ at 70 °C. The effect of various experimental parameters, such as deposition time and potential, on the electrocatalytic activity for the nitrate reduction was investigated. Surface analysis techniques (SEM, EDX and XRD) were used to get information on the morphology, the composition and the structure of the deposits. The activity of the modified electrode was studied by cyclic voltammetry, and amperometric method. The modified Mg(OH)₂/Cu sensor exhibited a good electrocatalytic behavior towards the reduction of nitrates with high reproducible reduction peak currents. In addition, the sensor exhibits a linear answer for concentration in nitrate between 0.125 to 7 mM, combined with high sensitivity (24.6 µA mM⁻¹ cm⁻²) and limit of detection (225.35 µM) values. When common interfering molecules were added to the solution, Mg(OH)₂/Cu electrodes have kept their good selectivity. They demonstrated acceptable detection levels for nitrates in tap water.

An unexpected route for the synthesis of pyrano [3,4-c] pyrrole derivatives has been reported via catalyst-free, three-component reaction of 1,3-dicarbonyl pyrazole, aromatic primary amines and fumaryl chloride. This novel cascade reaction sequence led to create two new rings and four new σ bonds containing two C–N, one C–C, and one C–O bond. The newly synthesized compounds were elucidated on the basis of their spectroscopic data (¹H, ¹³C, 2D NMR, HRMS, IR) and additionally confirmed by single-crystal X-ray diffraction analysis. The molecular docking simulation was performed utilizing the AutoDock 4.2 program to predict the binding affinity of one derivative of the synthesized compounds to the target mitogen-activated protein kinase P38 (MAPK P38) and mitogen-activated protein kinase 14 (MAPK 14).

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