جستجوی مقالات مرتبط با کلیدواژه "4-hydroxycoumarin" در نشریات گروه "شیمی"

Initially, a novel magnetic catalyst namely [Fe3O4@SiO2@Si-(CH2)3-Bipyr][ZnxCly] (FSCBZ) was fabricated, and its structure was corroborated using energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric (TG), and vibrating-sample magnetometery (VSM) analyses. In continue, it was employed to catalyze the solvent-free construction of bis-coumarins (from aryl aldehydes and 4-hydroxycoumarin) and bis(pyrazolyl)methanes (from aryl aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one). The coumarin and pyrazole derivatives were attained in short times (10-20 min) and high yields (89-98%). FSCBZ was reusable for two times with retaining its catalytic performance.

The strategic synthesis of 4-((4-Phenyl-5-Thioxo-1,2,4-Triazol-3-yl)methoxy)coumarin (PTTC) derived from 4-hydroxycoumarin is imperative, given its industrial, therapeutic relevance, and structural adaptability. This investigation delves into its multifaceted potential, particularly focusing on its anticorrosion, antibacterial, and antioxidant properties. Antibacterial efficacy against a spectrum of bacterial strains including Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, and Staphylococcus aureus was evaluated via the disk diffusion method, revealing robust microbiological activity with inhibition zones ranging from 11 to 28 mm. Furthermore, PTTC exhibited notable antioxidant prowess, demonstrating a maximum scavenging capacity of 95% in the DPPH radical scavenging assay. These results underscore PTTC's versatility as a therapeutic agent with promising applications. Its corrosion resistance potential for mild steel in 1.0 M hydrochloric acid was studied using weight loss methods. Parameters that influence corrosion inhibition such as PTTC concentration, which is a structural parameter, environmental temperature and immersion duration were all studied systematically. Particularly, the PTTC achieved high inhibition efficiencies that were at 96% at a 1.0mM concentration at 303K. The adsorption process on the metal surface was in accordance with the Langmuir adsorption isotherm, and both the experimental and theoretical results were in good agreement. The study presented discusses the PTTC's various functions and thereby, making it a good choice for different therapeutic purposes, corrosion prevention, and antioxidative activities.

A convenient and efficient procedure for synthesis of Bis(4-HydroxyCoumarin) derivatives has been developed by a simple one-pot, one step ultrasonic-assisted reaction to produce Bis(4-HydroxyCoumarins) in room temperature. The present methodology offers several advantages, such as a simple procedure with an easy work-up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.

In this research, a high efficient, simply and rapid method was applied for the synthesis of dihydropyrano[3,2-c]chromene derivatives by one-pot, three-component condensation of aldehydes, malononitrile and 4-hydroxycoumarin in H2O/ethanol (1:1 v/v) under reflux conditions. This reaction was run by using nano-silica supported 1,5-Diazabicyclo(4.3.0)non-5-en (DBN) which has been abbreviated as nano-SiO2/DBN under aqueous condition. The nano-SiO2/DBN catalyst was synthesized by reaction between silica chloride and DBN. The main advantages of this procedure are high yields, short reaction times and easy work-up. Furthermore, the catalyst could be reused for five times.

In this work, a rapid and highly effectual protocol for the synthesis of bis-coumarins has been developed. The one-pot quasi three-component reaction of aromatic aldehydes (1 eq.) with 4-hydroxycoumarin (2 eq.) in the presence of catalytic amount of protic acidic ionic liquid triethylaminium-N-sulfonic acid tetrachloroaluminate (TSAT) under solvent-free conditions afforded the mentioned compounds in high yields and short reaction times.

At first, potassium 2-oxoimidazolidine-1,3-diide (POImD) was prepared of stirring a mixture of imidazolidin-2-one, KOH and H2O overnight. Then, Potassium 2-oxoimidazolidine-1,3-diide was used as a green, novel, fast, efficient and mild catalyst for the synthesis of bis coumarinyl methanes via a one-pot reaction of one equivalent of various aromatic aldehydes and two equivalents of 4-hydroxycoumarin at room temperature in aqueous media. All reactions are performed in the absence of organic solvent in high to excellent yield during short reaction time. The procedure was readily conducted and affords remarkable advantages such as simple work-up, green media and eco-friendly procedure. The catalyst was recovered and reused. Apart from the mild conditions of the process and its excellent results, the simplicity of product isolation and the possibility to recycle the catalyst offer a significant advantage. To the best of our knowledge this is the first report on synthesis of POImD. All of synthesized compounds were characterized by IR, 1H and 13C NMR spectroscopy and elemental analyses.

In this study, we synthesized the benzopyrano[3,2-c]chromene-6,8-dione derivativesby one-pot multi-component reaction of 1,3-cyclohexanedione, arylaldehydes, and 4-hydroxycoumarin under the solventless condition using Cu(II)-Schiff base/SBA-15 as a reusable heterogeneous catalyst in high yields. These kinds of catalysts are built from mesoporous silica SBA-15 which is covalently anchored with Cu(II)-Schiff base complex. The high yields, simple work-up procedure, reuseability of the catalyst, and environmentally friendly conditions are the main advantages of this method compared to the other techniques. The products were identified by using 1H NMR, mass and IR spectra, which were compared to those reported previously.

Silica sodium carbonate (SSC) has been used as a valuable silica-supported catalyst for the preparation of a range of known and novel pyrano coumarins via the three-component reactions of aryl aldehydes, active methylene compound (malononitrile or ethyl cyanoacetate), and hydroxycoumarin (5,7-dihydroxy-4-substituted coumarins or 4-hydroxycoumarin). The heterogeneous catalyst showed much the same efficiency when employed in following reaction runs.

An efficient synthesis of chromenylphenylpropanone derivatives as warfarine-like analogues was developed by the Michael addition of 4-hydroxycoumarin to α,β-unsaturated compounds in the presence of polyvinylpolypyrrolidone supported antimony(III) chloride (PVPP-SbCl3) as a new polymeric Lewis acid catalyst in chloroform at reflux conditions without formation of 2,4-diarylpyrano[3,2-c]chromen-5(4H)-ones. The synthesized compounds were identified by FT-IR, 1HNMR and 13CNMR spectroscopic techniques and elemental analysis. Polyvinylpolypyrrolidone supported antimony(III) chloride was characterized via Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Clean methodologies, simple preparation of the catalyst, good yields, environmentally friendly and reusable catalyst are some advantages of this work.