Journal of Sulfur Chemistry最新文献

Herein, we performed grafting of thiol groups to the surface of multi-walled carbon nanotubes. Then, using them (CNTS), zinc oxide (ZnO), ethylene dichloride, and sodium trisulfide (Na₂S₃), poly(ethylene trisulfide) (PETS) nanocomposites were synthesized via in situ polymerization. After that, the samples were cured at 170°C using a rheometer. The structural characteristics of CNTS were identified by Fourier transform infrared (FTIR), Raman spectroscopies, and X-ray diffraction (XRD). The PETS characteristics were investigated by FT-IR, Raman, X-ray diffraction (XRD), and proton nuclear magnetic resonance (¹H NMR). Also, the samples were studied using scanning electron microscopy (SEM), Shore A, tensile tests, and differential scanning calorimetry (DSC). The results showed that CNTS has a significant effect on the curing time of the nanocomposites, so that the curing time decreases with increasing CNTS content. Moreover, the nanocomposites had improved mechanical properties, indicating that they are more resistant to deformation and fracture. In addition, after the curing process, the melting temperature (T m) was not observed, and by increasing CNTS in composites, the glass transition temperature (T g) occurs at higher temperatures. Furthermore, the hardness of the samples showed a slight increase with higher CNTS content.

This study describes the synthesis of novel chalconethiocarbohydrazones derived from 2′-hydroxychalcone and thiocarbohydrazide as potential drugs. The monothiocarbohydrazone (M1) and bisthiocarbohydrazone (M2) compounds were obtained by condensing thiocarbohydrazide with 2′-hydroxychalcone [1-(2-hydroxyphenyl)−3-phenyl-2-propen-1-one] at 1/1 and 1/2 mol ratios. The synthesized compounds were characterized by elemental analysis, ¹H NMR, FT-IR and UV-Vis spectroscopic techniques. The crystal structures of M1 and M2 were solved using single crystal X-ray diffraction method. The total antioxidant capacities of synthesized thiocarbohydrazones were determined by Cupric Reducing Antioxidant Capacity (CUPRAC) method. It was investigated also the radical scavenging activities of these compounds with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. When compared to standard compound Trolox, both of the compounds showed good antioxidant activity. For the new compounds, Conceptual Density Functional Theory (CDFT) computations were performed to compute important quantum chemical reactivity descriptors. The chemical reactivities of the studied chemical systems were compared via well-known electronic structure rules of CDFT. Experimentally determined antioxidant activities of the synthesized compounds were supported with Molecular Docking analyses.

Hydrofunctionalization is one of the most important transformation reactions of alkenes which allows for rapid increase in molecular complexity by installing functional groups across the carbon–carbon double bonds. In this context, over the past few years, the experimental synthesis of biologically important aliphatic sulfones through the hydrosulfonylation of olefinic double bonds has attracted tremendous attention due to its straightforward manner with high atom- and step-economy, and also easily accessible starting materials. The aim of the present paper is to perform a review of recent advances made on this research topic, with special emphasis on the mechanistic aspect of the reactions.

DMSO (dimethyl sulfoxide) plays an increasingly significant role in various synthetic processes by generating diverse active intermediates in situ, which actively participate in reactions. It is crucial to control the formation of these active intermediates to prevent their mutual interference during utilization. Our previous research identified methyl methanethiosulfonate (MMTS) as a major decomposition product of DMSO when catalyzed by small amounts of (COCl)₂ in CH₃CN. In the current study, we investigated how different solvents and additives can mediate the formation of MMTS. Complete avoidance of MMTS formation was achieved in 1,4-dioxane, while only trace amounts were observed in toluene, MTHF, or CHCl₃. Moreover, the decomposition pathway of DMSO in these solvents was effectively mediated through the addition of strong acids (HX, where X = TfO, ClO₄, I, Br, or Cl) or in the presence of LiI, CH₃I, or Br₂. The effects of solvents and additives on the decomposition of DMSO were explored. The possible mechanisms for the decomposition of DMSO under different conditions were proposed and discussed.

In this study, the residue of toxic 2-mercaptobenzothiazole, a semi-volatile heteroaromatic, was extracted from wastewater using a new spectrofluorometric method. The method is based on measuring 2-Mercaptobenzothiazole the quenching effect on the fluorescence intensity of ZnS quantum dot–gelatin nanocomposite in (pH 4, λ_ex 310 and λ_em 345 nm, in time 60 s). Different factors affecting the reaction were studied and optimized. The calibration plot is linear in the concentration range of (0.05–10.0 µgL⁻¹). The relative standard deviations and the detection limit of the method were ±1.0% and 0.05 μgL⁻¹, respectively. Observed, outcomes confirmed the suitability recovery and a meager detection limit for analyzing toxic 2-Mercaptobenzothiazole in water samples. The preliminary results from this study demonstrate that this new method can be used to analyze 2-mercaptobenzothiazole in wastewater.

The methanesulfenylation of various mercaptans and β-dicarbonyls has been investigated using in-situ generated methyl methanethiosulfonate (MMTS) from DMSO, facilitated by a catalytic amount of (COCl)₂. Employing the MMTS solution alongside Et₃N led to the synthesis of a range of unsymmetrical disulfides with good yields. Furthermore, the introduction of [²H₆]-DMSO enabled the successful preparation of various [²H₃]-disulfides. In the case of most β-dicarbonyls, successful methanesulfenylation was accomplished using Et₃N and DBU, resulting in favorable yields.

The reaction products formed in the SO₂ – ROH – (HOCH₂)₃CNH₂ (where R – CH₃, C₂H₅, n-C₃H₇, i-C₃H₇, n-C₄H₉ and n-C₅H₁₁) systems were isolated and identified as: binary salt – ammonium O-methylsulfite [(HOCH₂)₃CNH₃]⁺ [CH₃OSO₂]⁻ (1); 1/1 charge transfer complex between diethyl sulfite (2) and tris(hydroxymethyl)aminomethane by S-N binding; polymorhps of zwitterionic internal salt – O-sulfite tris(hydroxymethyl)methylammonium (at R – n-C₄H₉ and n-C₅H₁₁); and its solvates with n-propanol 1/1 (3) and isopropanol 2/1. The structures of all synthesized products were confirmed by FT-IR, Raman, ¹H NMR and ¹³C NMR spectrometry, and the structure of 1 and 3 was characterized by crystal X-ray diffraction studies as well.

Modeling stages of the cascade reaction of thiopyrano[4,3-b]indole-3(5H)-thiones and dimethyl acetylenedicarboxylate were studied. Alkylation of thiones with alkyl halides or dimethyl sulfate affording to thiopyrano[4,3-b]indole-2-ium salts models the first stage of the process. The attack at the 3-position of the obtained salts by secondary amines can serve as a model for the second stage of the cascade transformation; it gives 3-benzoylindoles with thioamide-group. Reactions of thiopyrano[4,3-b]indole-2-ium salts with primary amines lead to a series of γ-carbolines with thione group. The action of ammonia on these salts causes dealkylation and gives thiopyrano[4,3-b]indole-3(5H)-thiones.

Regarding the importance of thiol-thione tautomer structure and the existence of hydrogen bonding in thione tautomer structure and its effect on geometric, physicochemical, and biological properties, mono-cyclopentyl-substituted bismuthiol was synthesized via a telescopic process in a green medium. The pure product was characterized by physical and spectroscopic techniques. The suitable crystals for single crystal study were obtained after trying different solvents and mixed solvents, and long clear needle-like crystals could be isolated from a mixture of n-hexane and ethyl acetate (volume ratio of 8:2). The FTIR spectra of bismuthiol, 2,5-bis-cyclopentylsulfanyl-[1,3,4]thiadiazole, and 5-cyclopentylsulfanyl-3H-[1,3,4]thiadiazole-2-thione were studied to define the characteristic wavenumbers of thiol and thione structures. A possible hyper-conjugative interaction between the S–H and π bond of C=N, the existence of C=S and C–N–H. and stability of thione structure was demonstrated for the new product, which supports our prediction of thione or thiol structure using the study of IR spectra. Furthermore, the influence of change in 1,3,4-thiadiazol ring and the presence N–H functional group of thione structure on the transition phases and thermal stability of bismuthiol, bis-cyclopentyl-substituted, and mono-cyclopentyl-substituted bismuthiol were investigated using TGA/DTA and DSC profile analysis. The SwissADME tool was employed to predict the biocheminformatic information of bismuthiol, bis- and mono-cyclopentyl-substituted bismuthiols, which displayed high potential of all 1,3,4-thiadizole derivatives in pharmaceutical and medicine areas. Finally, an in vitro antibacterial activity of the mono- and bis-cyclopentyl substituted bismuthiol against the gram-negative (Escherichia coli ATCC 25922) and gram-positive (Staphylococcus aureus ATCC 25923) bacterial species was conducted by the disk diffusion method with cefazolin as a blank antibiotic. The results showed superior antibacterial efficiency of both derivatives.

Sulfonic acid-supported vanillin/bis indolylmethane-functionalized Fe₃O₄@SiO₂-Propyl NPs were prepared and characterized by FT-IR, XRD, FE-SEM, TEM, VSM, EDX, DLS, and TGA-DTG. The catalytic efficiency of the prepared nanoparticles was subsequently investigated for the effective synthesis of imidazoquinazolines via the one-pot condensation of 2-aminobenzimidazole, aryl aldehydes, and cyclohexanone or dimedone under solvent-free condition. Some thiazoquinazolines also were prepared via the multicomponent reaction of aldehydes, dimedone, and 2-aminobenzothiazol under solvent-free condition,. This avenue is really suitable because it makes a high yield of product, doesn’t take too long, doesn’t need harmful materials and solvents, its work-up is easy and the catalyst is reusable.