Journal of the Iranian Chemical Society最新文献

Six lanthanide complexes with substituted fenamic acid ligands {[La(L¹)₃].2H₂O (C1), [La(L²)₃].2H₂O (C2), [Ce(L¹)₃] (C3), [Ce(L²)₃].2H₂O (C4), [Pr(L¹)₃].3H₂O (C5) and [Eu(L²)₃] (C6); HL¹ = 2-(4-chlorophenylamino)benzoic acid and HL²= 2-(4-methoxyphenylamino)benzoic acid} were isolated and characterized by elemental CHN microanalyses, DMF solution electrical conductivities and spectral (FTIR and UV–Visible) data. These analyses assigned the monoanionic character of the ligands and their bidentate chelation mode through the carboxylate group oxygen atoms. In addition, the complexes dissolve in dichloromethane, dimethylformamide and dimethyl sulfoxide, and are nonelectrolytes. Thermo-analytical techniques (TG/DTA) analyzed the complexes in the air and revealed that all water contained in them is lattice-based (uncoordinated), while complexes C3 and C6 are anhydrous. Moreover, all complexes, during heating up to 700 °C, decomposed to the respective oxides (Ln₂O₃). The complexes were tested for potential activity against human MDA-MB-231 breast cancer cells and the results uncovered low cytotoxic effect with high IC₅₀ doses, comparing to paclitaxel, on these cells.

A new single crystal of p-aminomethylbenzoicdichloride hydrate C₈H₁₀NO₂·Cl·H₂O (Compound1) was obtained by slow evaporation. The structure was investigated by single-crystal X-ray diffraction which revealed that they crystallize in monoclinic, P2/c system space group and unit cell parameters: (a = 15.957(5) Å, b = 4.823(5) Å, c = 12.154(5) Å, β = 107.562(5)° and Z = 4). The asymmetric unit consisted of a combination of a chlorine ion⁻anion, one structural water molecule H₂O and an organic cation [⁺NH₃–CH₂–C₆H₄CO₂H]. The structural integrity is upheld through an intricate three-dimensional hydrogen network, serving as a stabilizing force for the crystal lattice. The cohesion between organic chain and chlorine Cl⁻ anion and H₂O molecule is assured by π-stacking and hydrogen bonds interactions N–H…Cl, N–H…OH₂ and C=O…H–O–C. The interaction has been thoroughly examined using Hirschfeld surface analysis. Furthermore, we employed density functional theory calculations to optimize the molecular structure. The micro-Raman spectroscopy measurements were taken to elucidate the vibration modes exhibited by the compound. Additionally, the material characteristic was probed using a deferential scanning calorimetry.

Electrochemical oxidation of o-tolidine has been assessed in a mixture (70/30) of buffer/acetonitrile and various pHs. The electrochemical results corroborate that the mechanism of electrooxidation of o-tolidine acidic, neutral, and alkaline solutions are different, and three pH zones with different oxidation mechanisms were obtained: in the first region, a reversible oxidation reaction under the E mechanism, in the second region, observing the two one-electron oxidation–reduction under the EC_DispE mechanism, and observation of the evidence of the ECE mechanism in the third region. In the continuation, electrosynthesis of a new azo compound has been reported in the third region. This process involves the electrochemical oxidation of o-tolidine in an aqueous phosphate buffer (pH = 7.2) in a divided cell using a carbon anode.

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Supercapacitors, thanks to their unique properties, are considered among the main future energy storage systems. However, problems such as low energy density relative to batteries, spontaneous discharge, and low cell voltage have limited their widespread use. In this regard, the development of active and efficient materials is known as a viable solution. Thus, in this study, a hybrid supercapacitor made of nickel oxide and graphene was investigated. Nickel oxide and graphene were synthesized by calcination of nickel hydroxide and electrochemical exfoliation of graphite, respectively. Nickel oxide–graphene composites were synthesized at three levels, including 10, 20 and 30%wt of graphene by a facile hydrothermal-calcination route. The samples were characterized by XRD, FE-SEM, elemental mapping and FTIR tests, and their electrochemical performance was evaluated by electrochemical measurements including CV and EIS tests. The result of the characterization tests confirmed the successful synthesis of nickel oxide, graphene and composites. The results of the electrochemical measurements also showed that the addition of graphene to nickel oxide improved the supercapacitive properties of pure nickel oxide. Improved performance of the composites was attributed to the less aggregation of graphene sheets and their greater conductivity. Based on the results of electrochemical tests, the optimum level of graphene addition was 20%wt and NiO@G20 supercapacitor in 2.0 M KOH medium and a scan rate of 5 (frac{{text{mV}}}{{text{s}}}) showed a specific capacitance of 915.40 (frac{{text{F}}}{{text{g}}}), energy density of 31.78 (frac{{text{Wh}}}{{text{kg}}}) and power density of 2.29 (frac{{text{kW}}}{{text{kg}}}). Also, NiO@G20 supercapacitor was able to maintain 96.7% of its initial capacitance after 5000 cycles, which shows its high cycle stability. The high and stable activity of NiO@G20 introduces it as a promising and high-performance material for supercapacitor.

A simple and efficient protocol for direct synthesis of multisubstituted 6-alkyl-4-chromenyl-1-aryl-3,4-dihydro-1H-pyrrolo[3,4-b]pyridine-2,5,7(6H)-trione derivatives is presented by a cascade reaction of 3-formylchromones, Meldrum’s acid and α-aminomaleimides as readily accessible starting materials. In this chemoselective, metal catalyst-free approach Michael addition/intramolecular cyclization and elimination of acetone and carbon dioxide occur consecutively. The significant advantages of this strategy are creating a C–N and a C–C bond, short reaction times, excellent yields (68–80%), and a metal-free catalyst.

Graphical Abstract

A simple and efficient protocol for direct synthesis of multisubstituted 6-alkyl-4-chromenyl-1-aryl-3,4-dihydro-1H-pyrrolo[3,4-b]pyridine-2,5,7(6H)-trione derivatives is presented by a cascade reaction of 3-formylchromones, Meldrum’s acid and α-aminomaleimides as readily accessible starting materials.

A new series of hybrids of α-tocopherol and aryl/heterocyclic moieties through 1,2,3-triazole linker were made by rationally combining a biologically active α-tocopherol and substituted aromatic or heterocyclic moieties in single molecular frame using the click chemistry method. In a nutshell, the novel compounds (3a-h) were made by O-alkylating α-tocopherol, proceeded by copper (I)-catalyzed click reaction and the Huisgen [3 + 2] cycloaddition using various aromatic and heterocyclic azides (2a-h). By using ¹H, ¹³C NMR, and mass spectroscopy techniques, all of the recently synthesized compounds were characterized and their antibacterial and antioxidant capabilities were assessed. Among the synthesized compounds, the most effective synthetic molecule against all bacterial strains was 3e with a naphthyl moiety, whereas 3d with a phenolic moiety showed potent antioxidant activity. To better understand the binding interactions, exploratory molecular docking investigation was conducted against the faBH enzyme of E. coli.

Formaldehyde (HCHO), a common industrial compound, presents major health hazards to people, underscoring the importance of HCHO sensor development in public health surveillance. This review encapsulates the advancements made in HCHO sensors over the last 3 years. An explanation is provided for the fundamental aspects of HCHO detection methods, which depend on resistive sensors, quartz crystal microbalance sensors, and fluorescence sensors, along with an exploration of the various sensing materials employed. Discussions also encompass prospective research pathways and obstacles. Creating HCHO sensors holds significant promise for enhancing both public health and environmental safeguarding.

Reactive oxygen species are known to have a harmful activity in living systems. It attracts the attention of researchers due to their capability of damaging crucial biomolecules such as nucleic acids, lipids, proteins, polyunsaturated fatty acids, and carbohydrates and which results many human ailments: atherosclerosis, cancer, diabetes, inflammation, cardiovascular diseases, and neurological disorders. Hence, the investigation of the already known compounds exhibiting antioxidant properties is still an important scientific challenge. So reaction with Co(II)-bound superoxo complex, [(NH₃)₅Co(O₂)Co(NH₃)₅]⁵⁺ (MBSC) and Popofol (PPF), Ferulic Acid (FA) is chosen to study the antioxidant activity of PPF and FA. Redox properties of Popofol (PPF) and Ferulic Acid (FA) which are two phenolic antioxidants are studied through the reduction of Co(II)-bound superoxo complex, [(NH₃)₅Co(O₂)Co(NH₃)₅]⁵⁺ (MBSC) in aqueous acidic media ([H⁺] = 0.02–0.70 M) under pseudo-first-order condition. For both the PPF and FA, the observed rate increase with the increase in [PPF] and [FA] and the decrease with media [H⁺] and ionic strength, I. The kinetic analysis reveals that the deprotonated conjugate bases from PPF and FA reduces MBSC with the diffusion-controlled rate of ~ 10⁸ and ~ 10¹¹ M⁻¹ s⁻¹. Since, the decrease in k_o values with increase in V/V D₂O were not significant, we can propose for a simple electron-transfer (ET) mechanism, rather than proton-coupled electron transfer (PCET) or hydrogen-atom transfer (HAT) mechanism for the reduction in bound superoxide by PPF and FA. The antioxidant property of propofol and ferulic acid has been evaluated by various methods but in our study, the novelty lies on the exploration of the real insight of their antioxidant property by studying the chemical mechanism of their redox properties with MBSC.

Due to their structural arrangements, coordination complexes have shown potential to combat various human diseases. Nitrogen heteroatoms are a fascinating class of coordination compounds with many applications in synthesis and medicine. Herein, four Co(II), Zn(II), Cu(II), and Ni(II) complexes (I–IV) such as [CoC₁₀H₁₄Cl₂N₆O₂] (I), [ZnC₆H₁₀Cl₂N₆O₂] (II), [Cu₂C₁₆H₃₄N₂O₁₂] (III), and [Ni₄C₈₀H₁₀₀N₁₆O₂₂] (IV) bearing aza-heterocyclic ligands have been synthesized under one-pot self-assembly conditions. The reaction of 2-amino-4-hydroxy-6-methylpyrimidine and 3-amino-5-hydroxypyrazole with CoCl₂·6H₂O and ZnCl₂, respectively, produced two mononuclear complexes (I)–(II) while two binuclear complexes (III)–(IV) (complex IV are in two halves) were synthesized using Cu (OAC)2·H₂O and NiCl₂·6H₂O, respectively, with salicylidene salicylhydrazide. Then, the complexes were characterized using NMR, FTIR UV–Vis, X-ray diffraction, TGA, and elemental analysis techniques to confirm their structures. The synthesis complexes were employed against different human tumour cell lines (SMMC-7721, A549, MDA-MB-231, and SW480). The best activity was demonstrated by complex (II) against human tumour cell lines SMMC-7721 (liver cancer cell) with an IC50 value of (6.356 µM).

Graphical Abstract

Lewis acid heterogeneous catalyst, ZnAl₂O₄/SiO₂ nanocomposite, was determined as a strong catalyst for the green and safe three-component reactions by the one-pot procedure. The effect of factors, such as the amount of catalyst, the molar ratio of reactants, reflux time and temperature on the three-component reactions were investigated. Also, the parameters of green chemistry were studied. These reactions under solvent-free conditions in the presence of ZnAl₂O₄/SiO₂ dramatically increased the yield of the formation of dihydropyrimidinones derivatives in a very short time. The results showed that ZnAl₂O₄/SiO₂ under solvent-free conditions greatly accelerate the three-component reactions with the advance of imine pathway and preventing the formation of unwanted side-products. Also, aromatic aldehydes with low electron density had the best outcomes. Lower reaction yield was produced by β-ketoesters with more steric hindrance. Without noticeably altering reaction time or yield, this catalyst employed six times. The technique is environmentally friendly, as shown by its low E-factor of 0.218–0.570 and high atom economy of 90.025–87.237.