Journal of the Iranian Chemical Society最新文献

An unexpected and selective synthetic technique was devised for 3-bromo-2-arylimidazo[1,2-a]pyridine and 3-formyl-2-arylimidazo[1,2-a]pyridine derivatives synthesis, utilizing DMSO and copper(II) bromide under time-controlled settings. Initially, the imidazopyridines underwent bromination, followed by the subsequent conversion of the brominated imidazopyridines into formylated imidazopyridines. This innovative technique has various advantages over previous ones, such as sequential synthesis of brominated and formylated imidazo[1,2-a]pyridines and, for the first time, utilizing CuBr₂ and DMSO as dual active agents simultaneously. This practical process can moreover produce two widely used products in the medical and pharmaceutical realm which increases its efficiency and adaptability.

Heavy metal pollution has become an increasingly prominent problem. Consequently, adsorbents with high heavy metal removal efficiency using a convenient synthesis method have to be developed urgently. The magnesium carbonate hydroxide microsheets modified activated carbon fiber (MCH@ACF) was prepared by a facile in situ hydrothermal method. The results of the characteristic of MCH@ACF indicated that a large amount of magnesium carbonate hydroxide porous microsheets is densely arranged on the surface of ACF. The Mn²⁺, Cu²⁺, Pb²⁺, and Cr₂O₇²⁻ ions adsorption kinetics of the MCH@ACF could be fitted with the pseudo-second-order model, and the results indicate the fast adsorption rate. The Mn²⁺, Cu²⁺, and Pb²⁺ ions adsorption on the MCH@ACF follow the Langmuir model, while the Cr₂O₇²⁻ adsorption on the MCH@ACF follows the Freundlich model. The theoretical adsorption capacity of the Mn²⁺, Cu²⁺, Pb²⁺, and Cr₂O₇²⁻ ions on the MCH@ACF is 558.6 mg/g, 1591.7 mg/g, 1802.8 mg/g, and 125.7 mg/g, respectively. The heavy metal ions removal performance of MCH@ACF under different pH conditions has been studied. Furthermore, the adsorption mechanism could be ascribed to the binding of heavy metal ions with carbonate or hydroxyl group. The results indicated that the MCH@ACF can be used as the potential suitable candidate for heavy metal removal.

Gold-coated magnetic iron oxide nanoparticles (ION) (Fe₃O₄@Au) were synthesized and utilized as catalyst for alcohol oxidation with tert-butyl hydroperoxide (TBHP). First, iron oxide magnetic nanoparticles (Fe₃O₄) were prepared and finally coated with a thin layer of gold. Structure and composition of Fe₃O₄@Au nanocatalyst were characterized by XRD, TGA, and FT-IR analysis. Size and morphology and size of particles were determined through TEM. Surface properties and topographies of coated nanoparticles were investigated by the AFM technique. The magnetic properties of Fe₃O₄ and Fe₃O₄@Au nanoparticles were measured by VSM technique. After confirming the structure of gold-coated magnetic ION, its performance for the oxidation of various aliphatic and aromatic alcohols with TBHP was studied in water. Finally, the reusability of Fe₃O₄@Au nanocatalyst was evaluated after five consecutive cycles in the 4-methoxybenzyl alcohol oxidation. The measured results revealed that the gold-coated iron oxide magnetic nanoparticles can be reused well in the oxidation processes of alcohols with high efficiency.

In this work, it is designed and synthesized therapeutically active anti-urease agents based on 3-bromosulfanilamide-based acyl thioureas (4a-j) through reaction of brominated sulfanilamide with aromatic acids via isothiocyanate formation and characterized by using FT-IR, 1HNMR, ¹³C NMR and MS analysis. The freshly prepared compounds were screened for in vitro urease inhibition assay. The derivative 4a with an un-substituted phenyl group showed IC₅₀ value of 17.02 ± 0.011 against urease as compared to the standard thiourea (IC₅₀ = 21 ± 0.12 µM). Structure activity relationship (SAR) revealed that the electronic and positional effects of substituents on phenyl ring play important role for the inhibition of clinically important enzymes. Additionally, in silico investigation was carried out which demonstrated that the compounds have exhibited polar and nonpolar interaction with the crucial residues in the binding site of urease. The in vitro and in silico studies are in agreement as per kinetics and docking results indicating that the synthesized 3-bromosulfanilamide-based acyl thiourea derivatives may serve as potential hits for the discovery of new urease inhibitors.

Numerous chemical and physical features of porous materials depend on the presence of metal ions in their structure. Metalated organic covalent frameworks (MCOFs), which are formed by combining organic covalent frameworks (COFs) with metal ions, integrate high-stability covalent bonds with flexible coordinate bonds and thus have the common characteristics of COFs and metal species such as extraordinary chemical stability, regular structure, and flexibility in design, high mechanical strength, low density, and permanent porosity. These characteristics have caused MCOFs to be used in various fields such as energy storage, measurement and analysis, biomedical applications, catalysis, molecular adsorption, and separation. Our review attempts to provide an overview of the recent research progress on the applications of MCOFs for the adsorption and separation of different pollutants. Strategies used for MCOF-based adsorption and separation applications, as well as existing challenges and future directions for research in this area, are summarized.

Adatoms on metallic surfaces appear to be inexpensive reversible surface alloys. Platinum nanostructured electrode (PtNPs) opens up new avenues in electrochemistry. The prepared platinum nanostructured on a tantalum substrate using a square wave potential regime was permitted to maintain an open circuit via a 1 × 10^–3 M solution that included an ion of one element Sb, Sn, As, or Pb. As a result, the closeness of the permanently adsorbed adatoms on the previously described Pt-nanostructured electrodes was proved by energy-dispersive X-ray spectroscopy, cyclic voltammetry and scanning electron microscopy. The electrocatalytic properties of prepared adatoms on new platinum nanostructures deposited on tantalum supporting structures were tested by the examination of electrooxidation of formic acid and methanol in 0.5 M H₂SO₄. The results of the previously mentioned tools showed the electrocatalytic characteristics of the nanoparticles ready exterior were improved by the adatoms of the four systems with varying levels of progress. The optimum conditions were set at 100 Hz frequency,  − 0.4 V, and 0.0 V below the square wave limits in addition, above at amplitude 0.4 V, to prepare nanostructured platinum deposits. The current peak (I_p) and the current of chronoamperometric (I_CA) of HCOOH solution oxidation on Pt-nanostructured Sn_ad (47 mAcm⁻², 130 µAcm⁻²) have higher values than As_ad (20 mAcm⁻², 55 µAcm⁻²), Sb_ad (34 mAcm⁻², 100 µAcm⁻²) and Pb_ad (24 mAcm⁻², 30µAcm⁻²)-Pt electrode.

The study utilizes the colorimetric method (involving 1,5-diphenylcarbazide and potassium thiocyanate as complexing agents), computer vision, and machine learning (ML) regression algorithms to determine the content of Cr (VI) and Fe (III) in water samples. To process digital images of water samples, the integration technique utilized a flatbed scanner known as the CanoScan LiDE 100, operating as a digital image capture device, and its performance was compared to that of conventional instruments. The study reveals that PolyReg and SVR-Poly are the most reliable ML regression algorithms for processing color space data (G and B of RGB, c* of CIELch, and b* of CIELab) of digital images of water samples that contain Cr (VI) and Fe (III). The mean absolute percentage error (MAPE) of the ML regression algorithms PolyReg and SVR-Poly for determining the content of Cr (VI) and Fe (III) is < 10% (with 8.48% error for Cr (VI) determination using PolyReg G of RGB and 6.78% error for Fe (III) determination using PolyReg B of RGB) in the estimation algorithm model. The Mean Absolute Percentage Error (MAPE) indicates that the prediction method is highly accurate. The Limit of Detection (LOD) value of the flatbed scanner colorimetric method integrated with PolyReg G of Red–Green–Blue (RGB) for Chromium (VI) and Blue of RGB for Iron (III) is approximately 0.02 mg/L. The Limit of Detection (LOD) for Chromium (VI) and Iron (III) is 0.0209 mg/L and 0.0257 mg/L, respectively. The limit of detection (LOD) values from this technique are superior to those obtained from certain UV–vis spectrometric and colorimetric methods. The low LOD values demonstrate that this technique is suitable for estimating the concentration of Cr (VI) and Fe (III) in water samples for quality assessment purposes, as these values are below the maximum concentration levels established by various regulations, including US-EPA, ASEAN, and EECCA.

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The magnetic biocompatible Fe₃O₄@Agar-Ag catalyst was designed and prepared based on a natural macromolecule (agar) through a convenient method using inexpensive, nontoxic, and easily available substances. Following synthesis, the catalyst underwent characterization using various techniques such as FT-IR, XRD, FE-SEM, EDX, VSM, TGA, and ICP. Subsequently, its efficacy was evaluated in treating breast cancer, in vitro. The results demonstrated the catalyst's effectiveness in reducing the proliferation of MCF-7 cells, suggesting its potential as an anticancer agent. Furthermore, our findings highlighted the biocompatibility of the synthesized nanoparticle and its lower toxicity toward normal cells.

A highly selective biosensor for glycine betaine (GB) based on the curcumin derivative (1BHD) is described, which displays a significant visual change and a lower detection limit (76 nM). The GB sensor displays a 1:1 binding ratio and a binding constant of 9.042 × 10⁷ M⁻¹. The binding mechanism of 1BHD for glycine betaine was confirmed by ¹H NMR titration, mass spectrometry, and DFT calculation. The fluorescence intensity of 1BHD was selectively quenched by GB, and an obvious color change from yellow to orange was observed by the naked eye. The above results have been utilized to detect GB sensitively in blood and urine samples.

Graphical Abstract

This research aimed to establish the quantification profiling of monosaccharides, sugar acids, stable carbon isotopes, and volatile organic compounds in stingless bee honey produced by Heterotrigona itama (H. itama) bee species employed with geographical discrimination study using chemometrics. In the present study, glucose (730.46–1948.99 µM) was detected in all honey samples; however, mannose (113.78 µM) and fucose (26.38 µM) were detected in only one sample (B2). On the other hand, glucuronic acid, galacturonic acid, ribose, rhamnose, galactose, xylose, and arabinose were absent in all the samples. δ¹³C values demonstrated that nectar composition in samples of this study originated from C-3 plants and no possible adulteration was deduced. Besides, a wide range of fifty-three volatile organic compounds (VOCs) was detected across the samples. The partial least square–discriminant analysis (PLS-DA) model illustrated an excellent geographical discrimination pattern of samples based on the studied variables. The PLS-DA model was validated using 10-fold cross-validation (R² = 0.84, Q²= 0.95, and accuracy = 0.93) and permutation test (p = 0.008). Variable importance of projection (VIP) exemplified thirteen VOCs (VIP > 1.4, p < 0.01) significant in the discrimination pattern and can be used as potent chemical markers. However, monosaccharides, sugar acids, and carbon isotopes were insignificant (VIP < 1.4, p < 0.01) in discriminating the stingless bee honey according to their geographical origins.