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A copper coordinated L-ascorbic acid (Cu@AACP) metal–organic framework was synthesized and characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), wavelength dispersive X-ray spectroscopy (WDX), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). The BET method was used to investigate the textural characteristics of Cu@AACP, including surface area, pore diameter and total pore volume. The SEM analysis was used to investigate the morphology and size of Cu@AACP particles. AAS, WDX and EDS techniques were used to investigate the elemental content of Cu@AACP. The TGA analysis was used to investigate the presence of solvents or moisture, thermal stability and organic–inorganic content of catalyst. The FT-IR spectroscopy was used to the characterization of functional groups in the structure of the materials. The XRD pattern was used to investigate the crystalline phase of the catalyst. The results of the analyses confirmed the successful synthesis of copper MOF of L-ascorbic acid (Cu@AACP). The catalytic performance of Cu@AACP was examined in synthesizing of 2, 3-dihydroquinazolin-4(1H)-ones (through condensation of aldehydes and anthranilamide in ethanol at 80 °C) and polyhydroquinolines (through condensation of aldehydes, dimedone, ammonium acetate and ethyl acetoacetate in ethanol at 80 °C). The reaction conditions for the synthesis of 2, 3-dihydroquinazolin-4(1H)-ones and polyhydroquinolines were optimized, where the best results were obtained in ethanol solvent at 80 °C in the presence of 6 mg of Cu@AACP as catalyst. The results show that an improved product yield is obtained between 84 and 95%. Recycle test of the catalyst confirmed that the heterogeneous catalyst exhibited good catalytic stability, efficiency and very high activity in successive runs because of its unique pore network. To show the stability of Cu@AACP nanocatalyst after recycling, the recovered catalyst was characterized by AAS, FE-SEM, EDS and FT-IR techniques. [ABSTRACT FROM AUTHOR]

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Terrestrial and aquatic environments contaminated with animal urine may contribute to the transmission of Leptospira, a causative agent of leptospirosis in humans and wild/domesticated animals. Although enormous amounts of work have been done decoding the ecophysiology, the factors governing the cell growth and virulence in Leptospires derived from environmental samples still remain elusive. Here, we show oxidation of a wide array of organic acids including acetoacetate by a new strain of Leptospira interrogans designated as KeTo, isolated from a sewage sample originating from a wildlife enclosure located at Mangalore, India. We further demonstrate the susceptibility of KeTo to ethyl ester of acetoacetate (ethyl acetoacetate, EA). A 4.7 Mbp genome of KeTo shared the highest relatedness to pathogenic L. interrogans RGAT (99.3%), followed by L. kirschneri 3522CT (91.3%) and other related species of Leptospira (80.8‒74.3%), and harbored genes encoding acetoacetyl-CoA synthetase and acetoacetate decarboxylase respectively involved in the acetoacetate utilization and acetone formation. In line with this, strain KeTo oxidized acetoacetate when supplied as a sole carbon. Aqueous EA suppressed biofilm formation (p < 0.0001) of KeTo in basal Ellinghausen–McCullough–Johnson–Harris (EMJH) medium. Similarly, significant inhibition in the growth/biofilm of Leptospira was recorded in semisolid EMJH with/without blood supplementation when exposed to volatile EA. The extent of ketone body oxidation and susceptibility to EA was found to vary with strain as evident through the analysis of L. interrogans serogroup Australis sv. Australis strain Ballico and L. interrogans serogroup Icterohaemorrhagiae sv. Lai Like strain AF61. In conclusion, our study demonstrated the ketone body metabolic ability and susceptibility to an esterified derivative of a major ketone body in the tested strains of L. interrogans. Molecular aspects governing EA-driven growth inhibition warrant further investigations to develop optimal therapeutics for leptospirosis. [ABSTRACT FROM AUTHOR]

The process of removing sulfur compounds and aromatic compounds to produce clean fuel is an important and effective contribution to the processes of mitigating and adapting to climate change. In contrast, it is necessary to find an innovative way to remove sulfur and carcinogenic aromatic compounds because clean, low-sulfur diesel is commonly used in all countries of the world at the present time. Therefore, in this work, we have studied the effect of the microwave radiation power and the irradiation time with the use of more than one type of organic solvent; methanol, acetonitrile and ethyl acetoacetate; as an extractant and solvent to feed ratio impact on the removal of sulfur and aromatic compounds of a real diesel fuel feed which has 450 ppm sulfur content and 16 wt% aromatic Content. The results showed that the best solvent used during this work was ethyl acetoacetate. According to the results, high sulfur removal (≈ 92%) was accomplished with microwave-assisted extractive desulfurization technique under the following ideal conditions: the irradiation time is 7 min, the solvent feed ratio is 3:1 and the microwave intensity is 180 W. To reveal the mechanism of microwave-assisted extractive desulfurization via different organic solvents, a theoretical study including structural examination and interaction energy analysis on the interaction between dibenzothiophene (DBT) or dimethyl dibenzothiophene (DMDBT) and the different organic solvents was also conducted. [ABSTRACT FROM AUTHOR]

An environmentally benign and expeditious protocol was developed for the one‐pot multicomponent synthesis of 4‐aryl‐3‐methylisoxazol‐5(4H)‐ones by the condensation of aldehyde, hydroxyl amine hydrochloride, and ethyl acetoacetate in 50% aq. ethanol at 50 °C. The reaction was catalyzed by magnetically separable carbon microspheres co‐decorated with nanosized iron sulfide and magnetite nanoparticles in 10 wt% amount. The FeS1‐x‐Fe3O4/C nanocatalyst was prepared from iron(III) sulfate loaded iminodiacetate group functionalized styrene‐divinylbenzene based ion exchanger by pyrolysis reaction performed at 600 °C for 4 h. The use of magnetically separable heterogeneous catalyst, aqueous ethanol, short reaction time (30 min), and nonchromatographic purification methods are the striking features of the developed protocol. The isolated yield of the condensation products varied between 81% and 96%. Furthermore, the protocol exhibits high functional group tolerance and includes the use of noncorrosive, nonhazardous reaction conditions affording the product in excellent yields and short reaction time. [ABSTRACT FROM AUTHOR]

A highly efficient protocol was developed for the synthesis of fructone spice from the ketalization of ethyl acetoacetate with ethylene glycol utilizing the sulfonated polydivinylbenzene (PDVB-SO3H) solid acid catalyst. A comparative analysis revealed that PDVB-SO3H exhibited better catalytic activity and reusability than conventional H2SO4 and p-toluene sulfonic acid. The impact of reaction conditions, including temperature, reaction time, catalyst dosage, and molar ratio of reactants, was extensively investigated in order to optimize the reaction parameters. The results revealed the remarkable catalytic efficiency of PDVB-SO3H in synthesizing apple ester flavor, achieving a conversion rate exceeding 99% under reflux conditions with a ketone to alcohol ratio of 1.5. Furthermore, PDVB-SO3H solid acid demonstrated its versatility by enhancing the synthesis of a variety of fruit ketone flavors with high conversion rates. Notably, the catalyst displayed excellent recyclability, remaining active for up to six cycles without any noticeable decline in performance. Therefore, PDVB-SO3H solid acid exhibits immense potential for utilization in the chemical industry. [ABSTRACT FROM AUTHOR]

At first, 1,4-Bis(pyridinium bi-sulfonic acid)benzene dimethylsulfonate (BPBSBDM), as a new Brønsted acidic ionic liquid (BAIL), is efficiently synthesized and revealed utilizing FT-IR (Fourier-transform infrared spectroscopy), TGA (thermogravimetric analysis), 13C NMR, 1H NMR and Mass data. Subsequently, its catalytic activity was studied in preparing bis(pyrazolyl)methane derivatives through the one-pot multicomponent coupled domino reactions (MCDRs) among 1 mmol aldehydes (aryl, heteroaryl, or alkyl aldehydes), 2 mmol ethyl acetoacetate, and 2 mmol phenylhydrazine/hydrazine hydrate under optimal conditions (50 °C, solvent-free, and 4 mol% of BPBSBDM) in high yields (89–98%), and in short times (2–7 min). Our protocol has the advantages of reasonable turnover number (TON: 22.25 to 24.50) and turnover frequency (TOF: 3.17 to 12.25 min−1) values, high yields of products, non-metallic nature of the catalyst, short reaction times, eco-friendly and economy, easy recyclability and good reproducibility. In addition, three derivatives 8a, 9a and 10a were synthesized and fully identified for the first time. [ABSTRACT FROM AUTHOR]

Novel ultrathin Cd-Ag-MOF@ZnO composite nanoribbons (Ut-Nr Cd-Ag-MOF@ZnO C) were prepared and characterized in this research to serve as organocatalyst in Hantzsch condensation for selective synthesis of asymmetric polyhydroquinolines through a one-pot multi-component condensation reaction of various substituted arylaldehyde, 5,5-dimethyl-1,3-cyclohexanedione, ammonium acetate and ethyl acetoacetate under solvent-free conventional heating in relatively short reaction times. The developed catalysts were easily recycled and reutilized at least three times under optimized reaction conditions with no noticeable decline in their initial catalytic activities. Operational simplicity and environmental compatibility, combined with the application of a reusable and affordable heterogeneous catalyst, significant efficiency, relatively short reaction time, and good yield are among the main characteristics of the proposed synthetic approach. [ABSTRACT FROM AUTHOR]

3‐methyl‐4‐(hetero)arylmethylidene isoxazole‐5(4H)‐one derivatives (4a‐r) derivatives (4a‐r) were synthesized by the multi‐component reactions. The multi‐component reactions (MCRs) of hydroxylamine hydrochloride, ethyl acetoacetate and aromatic/ heteroaromatic aldehyde catalyzed by novel Glutamic acid (Glu) as a biodegradable and eco‐friendly organocatalyst in ethanol on oil bath stirring at 60 °C. The final product homogeneity was examined by various spectroscopic techniques. In this work prepared compounds 4 q and 4 r are novel derivatives. The molecular dynamics of total energy and energy gap was calculated using DFT/B3LYP/6–31G (dp) method. The selected derivatives (4 l–r) screened against in vitro MCF‐7 breast cancer cell line by MTT assay, derivatives 4 l and 4 o displayed very good activity with IC50 of 6.57±2.31, and 21.93±1.34 as compared to doxorubicin of IC50 (3.69±0.17). Molecular docking studies were performed to evaluate interaction of PDB id: 1 M17 with led molecules of MCF‐7. Later, 1 M17 and 4 l underwent 200 ns molecular dynamics and simulation within physiological conditions, the outcomes showed that during the simulation, the ligand stayed in the same form. Further, the selected derivatives drug like computed using swissADME, and derivatives 4 l–r obeyed rule of Lipinski's. Furthermore, selected derivatives tested for electrochemical behavior using cyclic voltammetry, and compound 4 l and 4 q showed strong oxidation and reduction potential, thus these derivatives can present better antioxidant properties. [ABSTRACT FROM AUTHOR]

This article discusses the use of phytic acid (PA) as a catalyst in the synthesis of coumarins through the Pechmann condensation reaction. PA is a naturally sourced and environmentally friendly catalyst that efficiently catalyzes the reaction with high yields. The article explores the scope of the reaction, demonstrating the synthesis of several substituted coumarins. Coumarins have significant biological activities, making this research valuable for the development of new drugs and treatments. The authors also provide detailed experimental procedures and characterization data for the synthesized compounds. The authors hope that this eco-friendly method can be used to create other important heterocyclic systems in a more environmentally friendly way. [Extracted from the article]

This article discusses a new method for synthesizing 4-arylideneisoxazolones, which are compounds with various biological and pharmacological properties. The authors present a three-component reaction using Na2SO3 as a catalyst in an aqueous medium, which is an environmentally friendly procedure. The optimal conditions for the synthesis are determined, and the results for different types of aldehydes are summarized. The authors also include DFT calculations to better understand the stability and reactivity of the compounds. The research was supported by the Algerian Ministry of Higher Education and Scientific Research. [Extracted from the article]

Abstract The process of removing sulfur compounds and aromatic compounds to produce clean fuel is an important and effective contribution to the processes of mitigating and adapting to climate change. In contrast, it is necessary to find an innovative way to remove sulfur and carcinogenic aromatic compounds because clean, low-sulfur diesel is commonly used in all countries of the world at the present time. Therefore, in this work, we have studied the effect of the microwave radiation power and the irradiation time with the use of more than one type of organic solvent; methanol, acetonitrile and ethyl acetoacetate; as an extractant and solvent to feed ratio impact on the removal of sulfur and aromatic compounds of a real diesel fuel feed which has 450 ppm sulfur content and 16 wt% aromatic Content. The results showed that the best solvent used during this work was ethyl acetoacetate. According to the results, high sulfur removal (≈ 92%) was accomplished with microwave-assisted extractive desulfurization technique under the following ideal conditions: the irradiation time is 7 min, the solvent feed ratio is 3:1 and the microwave intensity is 180 W. To reveal the mechanism of microwave-assisted extractive desulfurization via different organic solvents, a theoretical study including structural examination and interaction energy analysis on the interaction between dibenzothiophene (DBT) or dimethyl dibenzothiophene (DMDBT) and the different organic solvents was also conducted.

Currently, there is a growing interest in the synthesis of heterocyclic compounds containing hydroquinoline fragments. This surge can be attributed to the broad range of pharmaceutical and industrial applications that these compounds possess. In this study, the synthesis of both linear and fused heterocyclic systems that incorporate hydroquinoline fragments was described. Furthermore, the pharmacological activity spectra of the synthesized compounds were predicted using the in silico method, employing the Prediction of Activity Spectra of Substances (PASS) program. Hydroquinolines containing the nitrile functionality 7 and 8 were synthesized through the reaction of the corresponding hydroquinolinecarbaldehyde 5a, 6b with hydroxylamine hydrochloride and iodine in aqueous ammonia under ambient conditions, respectively. 2-Phenyl-1,3-oxazol-5(4 H)-ones 9a, b and 10a, b were synthesized via the condensation of compounds 5a, b and 6a, b with hippuric acid in acetic acid in 30–60% yield. When the methyl activated 7-methylazolopyrimidines 11a, b were reacted with N-alkyl-2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline-6-carbaldehydes 6a, b, 60–70% yield of triazolo/pyrazolo[1,5-a]pyrimidin-6-yl carboxylic acids 12a, b were obtained. The condensation of 7-hydroxy-1,2,3,4-tetramethyl-1,2-dihydroquinoline 3 h with dimethylacetylenedicarboxylate (DMAD) and ethyl acetoacetate afforded cyclic products 16 and 17, respectively. The condensation reaction of 6-formyl-7-hydroxy-1,2,2,4-tetramethyl-1,2-dihydroquinoline 5e with methylene-active compounds such as ethyl cyanoacetate/dimethyl-3-oxopentanedioate/ethyl acetoacetate/diethylmalonate/Meldrum's acid afforded 3-substituted coumarins 19 and 21 containing dihydroquinoline moiety. The pentacyclic coumarin 22 was obtained via the tandom condensation reaction of malononitrile with 5e in the presence of a catalytic amount of piperidine in ethanol. The biological activities of the synthesized compounds were predicted using the PASS program. Based on the prognosis, compounds 13a, b, and 14 exhibited a high likelihood of being active as inhibitors of gluconate 2-dehydrogenase, as well as possessing antiallergic, antiasthmatic, and antiarthritic properties, with a probability value (Pa) ranging from 0.849 to 0.870. Furthermore, it was discovered that compounds 7 and 8 tended to act as effective progesterone antagonists and displayed antiallergic, antiasthmatic, and antiarthritic effects (Pa = 0.276–0.827). Among the hydroquinolines containing coumarin moieties, compounds 17, 19a, and 19c were predicted to be potent progesterone antagonists, with Pa values of 0.710, 0.630, and 0.615, respectively. [ABSTRACT FROM AUTHOR]

In this research, a novel and efficient nanocatalyst, namely, palladium immobilized onto 1,4-bis(pyrid-4-yl)benzene grafted to n-propyl-functionalized Fe3O4@MCM-41 nanoparticles (PBPBPMF), was synthesized and introduced. Then, its catalytic activity was tested in the synthesis of bis(pyrazolyl)methane (14 examples, 90–97%, 9–25 min, solvent-free, 60 °C) and biphenyl (13 examples, 80–98%, 10–120 min, PEG-400, 70 °C) derivatives. Bis(pyrazolyl)methane derivatives were synthesized via a one-pot pseudo-five-component reaction of aldehydes, ethyl acetoacetate, and phenylhydrazine, and biphenyl derivatives were obtained by a Stille coupling reaction. Transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), N2 sorption isotherms, vibrating sample magnetometer (VSM), inductively coupled plasma atomic emission spectrometer (ICP-OES), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and elemental mapping analyses were used to identify the catalyst. The PBPBPMF is a heterogeneous catalyst with several advantages, including a large specific surface area, ease of purification, and separation from the reaction mixture; furthermore, the nanocatalyst was recycled six times without appreciably altering its catalytic properties. [ABSTRACT FROM AUTHOR]

MOF supported on the red soil was synthesized thru simple method by Cu˗MOF and red soil with ratio of 1 : 5. The structure and morphology of MOF supported on the red soil was considered by FTIR and Raman spectroscopy, FESEM, TGA and BET methods. The results showed MOF supported on the red soil have mesoporous nanostructure (20–25 nm). A simple and efficient synthesis of tetrazolo[1,5-a]pyrimidines was accomplished by three-component reaction of a mixture of aromatic aldehyde, 5-aminotetrazole and ethyl acetoacetate or methyl acetoacetate using MOF supported on the red soil as heterogenic catalyst. The reactions were carried out in water and ethanol at 70°C. MOF supported on the red soil operated as a sufficient recyclable, effective, low cost and eco-friendly catalyst for synthesis of tetrazolo [1,5-a] pyrimidines. [ABSTRACT FROM AUTHOR]

Herein, the classic organic chemistry experiment titled "Determination of Ethyl Acetoacetate Tautomers by 1H Nuclear Magnetic Resonance" was redesigned to enhance its scope and depth. This new experiment goes beyond simply recognizing the keto-enol tautomeric phenomenon. It delves into the kinetics, the impact of substituents, and the influence of solvents on the keto-enol tautomerization. It's worth noting that the hydrogen-deuterium exchange phenomenon can be observed, providing valuable insights into the ketone-enol tautomeric mechanism. This wellcrafted experiment is designed for senior undergraduate students pursuing chemistry-related majors. It not only deepens their comprehension of ketone properties but also fosters expertise in utilizing nuclear magnetic resonance spectroscopy in the field of organic chemistry. This, in turn, solidifies their theoretical knowledge in organic chemistry and instrumental analysis and hones their problem-solving and analytical skills. [ABSTRACT FROM AUTHOR]

This article explores the use of ketone-derived pro-aromatic reagents for radical group transfer reactions and deconstructive functionalizations. It discusses the recent advancements in using ketones as synthetic handles for sp3-rich radicals, specifically focusing on the use of ketone-derived pro-aromatic reagents for C-C bond activation. The article highlights the synthesis and utilization of these reagents in both photochemical and non-photochemical reactions, showcasing their potential in organic radical chemistry. The authors also discuss the applications of DHQZ derivatives as radical precursors in various photoredox reactions, demonstrating their effectiveness in generating different types of alkyl and acyl radicals. The article emphasizes the versatility and potential of ketones as valuable tools in synthetic chemistry, while acknowledging the contributions of researchers from different institutions and expressing gratitude to Prof. Evelyn Creencia on her retirement. [Extracted from the article]

This document provides information on the synthesis and characterization of 1,4-dihydropyridine (1,4-DHP) compounds using N,N-dimethylenaminones, arylamines, and dimethylethanolamine (DMEA) as reactants. The reaction is catalyzed by FeCl3 and proceeds through a four-component cyclization. The protocol demonstrates good functional group tolerance and offers a diverse range of 1,4-DHP derivatives. The synthesized products also exhibit promising photophysical properties. The document includes data such as nuclear magnetic resonance (NMR) spectra, melting points, and mass spectrometry results for each compound, which can be useful for researchers studying the synthesis and properties of these compounds. [Extracted from the article]

ω-Transaminases (ω-TAs) are significant candidate enzymes in the biosynthesis of chiral amines for the pharmaceutical and chemical industries. Novel thermostable ω-TAs for potential use in these industries can be discovered using homologous sequence alignment. In this study, we used well-studied B3-TA from hot spring metagenomes, the Sbv333-TA from Streptomyces sp., and TATR from Thermomicrobium roseum as starting templates to BLAST search, and found a yet unidentified thermostable ω-TA (TATP) from Thermorudis peleae. We cloned TATP into vector pET28a, leading to pET28a-TATP, and overexpressed it in Escherichia coli. The enzyme showed the highest activity at pH 8.8 and 73.6 °C, with remarkable thermostability and tolerance toward organic solvents methanol and ethanol. Substrate specificity analysis showed that TATP enzyme is active toward a broad range of substrates including glyoxylate, pyruvate, 2-phenylpropionaldehyde, 2-oxobutyrate, propionaldehyde, acetaldehyde, ethyl acetoacetate, etc. Especially, TATP enzyme presented relatively good activity toward pyruvate and glyoxylate. In addition, the active sites of TATP were analyzed via the approaches of protein sequence alignment, three-dimensional structure simulation, and coenzyme pyridoxamine phosphate docking, which provided a guideline for further enzyme engineering and suggested a potential industrial thermostable ω-TA for chiral amines synthesis. [ABSTRACT FROM AUTHOR]

Dienamine 2 was synthesized by reacting 5‐aminopyrazole 1 with two moles of (DMF DMA). Enamine 2 underwent subsequent reactions with various reagents in different reaction media, leading to the formation of distinct compounds. In an acidic environment, enamine 2 reacted with acetyl acetone, benzoyl acetone, dimedone, and ethyl acetoacetate, resulting in the synthesis of compounds 9a, 9b, 13, and 17, respectively. Conversely, in a basic medium, dienamine 2 combined with malononitrile, ethyl cyanoacetate, and malononitrile dimer, yielding compounds 21a, 21b, and 25. Moreover, by reacting with ammonium acetate in acetic acid, dienamine 2 produced compounds 28. The synthesized compounds underwent in vitro testing against various bacterial and fungal strains, revealing significant antibacterial activity against hazardous bacterial strains. To identify potential bacterial targets, an in‐silico study was initiated. Molecular docking investigations indicated that compound 25 exhibited the highest binding affinity toward dihydrofolate reductase and penicillin‐binding proteins. Furthermore, compound 25 demonstrated robust physiochemical properties, bioavailability, and drug‐like characteristics. These results collectively suggest the potential of compound 25 as a promising antibacterial agent with favorable drug properties. [ABSTRACT FROM AUTHOR]

An expedient, green, practical, and vastly efficient three-component cyclo-condensation is catalyzed by triphenylphosphine. The 4-arylideneisoxazol-5(4H)-one heterocycles are generated in good to excellent isolated reaction yields. Experiments show that the best results were obtained using 15 mol% of the catalyst under aqueous conditions at room temperature. The sonochemical synthesis of 4-arylideneisoxazol-5(4H)-one derivatives were also performed by using 10 mol% of triphenylphosphine in water as an eco-friendly reaction medium. In the comparative method, ultrasonication showed shorter reaction times and also requires smaller amounts of catalyst. While aryl/heteroaryl aldehydes were used, the variation of β-keto-ester was also explored. The β-keto-esters (ethyl acetoacetate/ethyl 4-chloro-3-oxobutanoate/ethyl 3-oxohexanoate) under optimized reaction conditions reacted well and afforded the corresponding 4-arylideneisoxazol-5(4H)-ones in shorter reaction times. The approach is simple, approximately compatible with the pot-, atom-, and step-economy. [ABSTRACT FROM AUTHOR]

Condensation of chloromethyl chlorosulfate (1) with alkyl 1,3‐keto esters under phase‐transfer catalysis (PTC) conditions led to methylene bridged bis‐acetoacetates through a sequential chloromethylation‐β‐elimination‐Michael addition process. The latter compounds further evolved towards polyfunctional dihydrofuran and tetrahydropyran derivatives by competitive chloromethylation/chlorination reaction. In aprotic organic solvent, chlorination of the methylene active group is the main process and proceeded by reaction of the enolate of acetoacetate with the chlorine atom bound to the sulfonyl group of 1. The reactivity of some other active methylene compounds under PTC conditions was investigated. Acetylacetone reacted similarly to ethyl acetoacetate providing O‐heterocycles while ethyl cyanoacetate gave diethyl 2,4‐dicyanoglutaric acid diethyl ester together with 2‐diethyl 1,2‐dicyanocyclopropane‐1,2‐dicarboxylate. A plausible reaction mechanism is proposed whose the key feature is the competitive halogenation/chloromethylation of the intermediate methylene bridge dimeric active methylene compounds followed by intramolecular cyclization. [ABSTRACT FROM AUTHOR]

The pursuit of advanced multifunctional compounds has gained significant momentum in recent scientific endeavours. This study is dedicated to elucidating the synthesis, rigorous characterization, and multifaceted applications—encompassing anti-corrosion, antimicrobial, and antioxidant properties—of Diethyl 4-(5-bromo-1H-indol-3-yl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate. The 1,4-dihydropyridine derivative was meticulously synthesized through a strategic reaction of ethyl acetoacetate, ammonium acetate, and 5-bromoindole-3-carboxaldehydein the ethanol medium at 60 C. Subsequent spectral validations were conducted using sophisticated techniques, namely FTIR, NMR, and Mass spectrometry, resulting in data that perfectly resonated with the hypothesized chemical structure of the compound. Its anti-corrosive potential was assessed on mild steel subjected to an aggressive acidic environment, employing comprehensive methodologies like gravimetric analysis, Tafel polarization, and EIS. Concurrently, its antimicrobial prowess was ascertained against a spectrum of bacterial and fungal pathogens viz., Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas, Candida albicansandAspergillusniger, leveraging the disc diffusion method and using Gentamicin as a reference standard.The empirical results illustrated a substantial decrement in corrosion rates with ascending concentrations of the organic compound, achieving an apex of anti-corrosive efficacy at 81.89% for a concentration of 2 × 103 M. Furthermore, the compound outperformed Gentamicin in antimicrobial screenings, manifesting superior efficacy against all tested pathogens. The antioxidant potential, quantified using the DPPH free radical scavenging assay against ascorbic acid as a benchmark, was found to have an IC50 value of 113.964 ± 0.076 µg/ml.This comprehensive investigation accentuates the paramount potential of the synthesized dihydropyridine derivative in diverse domains—from industrial applications as a corrosion inhibitor to therapeutic avenues given its pronounced antimicrobial and antioxidant capabilities. The compelling results obtained pave the way for expansive research and development initiatives cantered around this multifaceted compound. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the anticancer potential of the novel 5,6,7,8-tetrahydro-4H-chromenes against selected six cancer cell lines together with the prostate cancer cell line PC-3. A novel series of substituted 5,6,7,8-tetrahydro-4H-chromenes were synthesized through feasible synthetic strategy. The synthetic schemes involve firstly the multi-component reactions of dimedone with the aromatic aldehydes and ethyl acetoacetate to produce the 5,6,7,8-tetrahydro-4H-chromenes derivatives. On the other hand, carrying the same reactions using NH4OAc produced the hexahydroquinoline compounds. Anti-proliferative evaluations and inhibitions for all synthesized compounds toward selected cancer cell lines were carried out and the results revealed that many of them exhibited high inhibitions. Morphology of A549 cell line by the effect of compounds 14f and 16c was performed. [ABSTRACT FROM AUTHOR]

The immobilization of homogeneous catalytic material over suitable heterogeneous support is amongst the recent strategies to minimize the shortcomings and unite the merits of homogeneous and heterogeneous catalysts. However, the physisorption-based immobilization does not serve the purpose because of its temperature as well as solvent dependent highly reversible nature. In the present work, a new catalytic material silica bonded bis(hydrogensulphato)benzene (SiO2-BHSB) was developed through the chemisorption of benzene-1,3-disulfonic acid as an active catalytic material over the surface of micro-sized silica. The synthesis, structure, purity, thermal stability and acid strength of the newly synthesized catalytic material were confirmed by appropriate analytical techniques such as solid-state CP-MAS 13C-NMR, CP-MAS 29Si-NMR, FT-IR, EDX, TGA, DSC and volumetric studies. An efficient and environmentally benign catalytic protocol for the synthesis of highly substituted 4H-pyran scaffolds was developed, in which a small amount of SiO2-BHSB (3 mol%) was observed sufficient to promote a tandem reaction between alkyl acetoacetate, malononitrile and structurally diverse aldehydes to offer good to excellent yields of 4H-pyran derivatives in aqueous based solvent. Structures of the synthesized 4H-pyran derivatives were confirmed by suitable characterization techniques. The catalytic material was observed to have enough catalytic potential to exhibit sustained catalytic activity even after five cycles of its reuse. Features such as presence of two -SO3H groups, strong acidic character, organo–inorganic hybrid nature, highly stable and chemically inert silica base, high heat of adsorption, large surface area and effective pore volume make SiO2-BHSB a versatile and convenient catalytic material. Herein described catalytic protocol stood better in terms of convenient recovery and reuse of catalyst, waste minimization, environment safety, aqueous based solvent, normal energy conditions and operational simplicity than majority of the cited protocols. [ABSTRACT FROM AUTHOR]

Discovered in the 19th century, ethyl acetoacetate has been central to the development of organic chemistry, including its pedagogy and applications. In this study, we present borylated derivatives of this venerable molecule. A boron handle has been installed at either α ${{\rm \alpha }}$ ‐ or β ${\beta }$ ‐position of acetoacetate by homologation of acyl‐MIDA (N‐methyliminodiacetic acid) boronates with diazoacetates. Either alkyl or boryl groups were found to migrate with regiochemistry being a function of the steric bulk of the diazo species. Boryl β ${{\rm \beta }}$ ‐ketoesters can be further modified into borylated pyrazolones and oximes, thereby expanding the synthetic toolkit and offering opportunities for additional modifications. [ABSTRACT FROM AUTHOR]

This article introduces a highly proficient and environmentally friendly process for producing pyranopyrazole-5-carbonitriles with outstanding yields. This involves a multicomponent synthesis using commonly available aldehydes, malononitrile, ethyl acetoacetate, and phenylhydrazine, conducted in ethanol with perchloric acid supported on silica (HClO4-SiO2) as a solid catalyst. Utilizing HClO4-SiO2 as a reusable catalyst underscores the sustainability of this approach, offering a valuable green chemical strategy for pyranopyrazole synthesis. Characterization of the synthesized compounds was achieved using FTIR, 1H NMR, 13C NMR, and Mass spectrometry. Additionally, molecular docking studies revealed significant binding energies of the compounds to receptor-active sites, further validating their potential pharmacological relevance. [ABSTRACT FROM AUTHOR]

The significant medicinal and pharmacological facts about chromenes (benzopyran) nucleus prompted us to focus on constructing unique chromenes with biological value. New chromene derivatives 2–15 were synthesized, and their antibacterial effectiveness was studied. The reaction of the 2-amino-4H-chromene derivative 1 with a variety of reagents such as acetic anhydride, formic acid, chloroacetyl chloride, cyclopentanone, ethyl acetoacetate, diethyl malonate, aldehydes, and isatin produced derivatives 2–13. Compound 1 was also treated with aromatic amines such as p-toluidine and/or benzene-1,4-diamine with formaldehyde, yielding derivatives 14 and 15, respectively; spectral techniques were used to confirm the predicted structures of all compounds. The antibacterial activity of the recently synthesized compounds was assessed against two types of bacteria, Bacillus subtilis and Escherichia coli. There is encouraging antibacterial activity in compounds 5 and 7. [ABSTRACT FROM AUTHOR]

In this work, an efficient and expeditious synthesis of a series of new benzo[d]thiazole derivatives has been reported starting from the reaction of 2-aminothiophenol with different esters such as ethyl cyanoacetate, diethylmalonate or ethyl acetoacetate to produce benzo[d]thiazole derivatives. The latter compounds underwent multi-component reactions with aromatic aldehydes and cyclohexan-1,3-dione using two different conditions first the use of solvent and regular catalyst and secondly using solvent free ionic liquids immobilized multi-component was studied. Comparison between the yields in the two methods was recorded. The benzo[d]thiazole derivatives were characterized by extensive analytical and spectral studies and were further used as starting materials for some heterocyclic transformations to produce biologically active compounds. Most of the tested compounds exhibited high cytotoxicity except few compounds. All tested compounds exhibited greater inhibitory action than the reference drug Doxorubicin against HeLa cell line except six compounds. The most cytotoxic compounds were 8h, 10e, 12b, 12i, 14b, 14h, 14i and 15i with IC50's 0.21, 0.26, 0.32, 0.19, 0.32, 0.27, 0.25 and 0.18 µM, respectively against HepG2 cell line. In addition, the majority of the tested compounds emerged as c-MET kinase and PC-3 cell inhibitors which revealed that most of the tested compounds showed from moderate to good inhibitions. [ABSTRACT FROM AUTHOR]

Potentially biologically active functionally substituted thiadiazolopyrimidines were obtained via three-component condensation of 5-amino-1,3,4-thiadiazole-2-thiol with aromatic aldehydes and CH-acids (acetoacetic ester and malononitrile). Probable mechanisms for the formation of products are suggested. Quantum-chemical calculation of the aminating reagent molecule 5-amino-1,3,4-thiadiazole-2-thiol showed the preference of the amino group as the most active nucleophilic center. The study of molecular docking shows the potential for binding one of the representatives of the thiadizolopyrimidine series and cytidine deaminase. The structure of the new compounds was established using IR and 1H NMR spectroscopies. [ABSTRACT FROM AUTHOR]

In the present research, the design and synthesis of polyfunctionalized pyrrole derivatives using one-pot, multi-component reactions including aromatic aldehydes, ethyl acetoacetate, thiadiazole derivatives, and nitromethane in the presence of 3-sulfonic acid 1-imidazolopyridinium hydrogen sulfate ([Simp]HSO4]) ionic liquid and under solvent-free conditions were discussed. Since pyrrole derivatives have various medicinal properties such as antibacterial, antiviral, anti-inflammatory, and antioxidant activity, and they are very important from biological and medicinal points of view, therefore, it is very important to provide efficient and green methods for preparing these compounds.On the other hand, considering the environmental pollution and the development of the green chemistry approach, and the recommendation to reduce the use of toxic solvents in chemical reactions, extensive research to find new synthetic methods based on the use of environmentally friendly solvents and catalysts that lead to the reduction of waste materials and products. This method used the ionic liquid 3-sulfonic acid 1-imidazolopyridinium hydrogen sulfate ([Simp]HSO4]) as a recoverable catalyst in the green synthesis of pyrrole derivatives.This method has some advantages such as high yield, no use of organic solvents, mild reaction conditions, short reaction time, and easy separation without using chromatography. The structure of all products was characterized using physical data as well as ¹HNMR, 13CNMR and IR spectrum. [ABSTRACT FROM AUTHOR]

Pristine magnesium spinel ferrite nanoparticles (MgFe2O4, MNPs) were fabricated via sol–gel auto combustion and elucidated by XRD, SEM, EDAX, TEM, FTIR, BET and VSM for structural and physical characteristics. Fabricated MgFe2O4 MNPs found to be an efficient, robust and magnetically separable reusable heterogeneous catalyst for one pot three component solvent free synthesis of biologically important 1,4-dihydropyridines (1, 4 DHP's) via Hantzsch condensation reaction. This convention was effectively appropriate to an extensive variety physically distinct aryl-aldehydes with ethyl acetoacetate and ammonium acetate to manage the required 1,4-dihydropyridines (1, 4 DHP's) derivatives. The structural investigations approved the sustainability and reusability of the MgFe2O4, MNPs towards current organic reactions. The novelties of this protocol are operational cleanness, short reaction time, nontoxic, inexpensive and magnetically separable heterogeneous catalyst may perhaps easily be recycled deprived of remarkable decline in catalytic performance. [ABSTRACT FROM AUTHOR]

The syntheses of pyrimidinone derivatives by the Biginelli reaction in N-methylpyridinium methyl sulfate [mPyrMeSO4] as an ionic liquid medium have been reported. This protocol provides a highly efficient and selective route for the synthesis of structurally diverse pyrimidinones under milder reaction conditions. The proposed conditions tolerate differently substituted aldehydes and ketones and afford products in synthetically useful yields. Furthermore, camphor, benzil, benzoin, and ethyl acetoacetate were utilized for the Biginelli reaction for the first time, and the resulting pyrimidinones were obtained in excellent yields. [ABSTRACT FROM AUTHOR]

Zinc alumotitanate sorbents with various compositions were prepared through sol-gel synthesis with the use of ethyl acetoacetate as a chelating agent. The formation and decomposition of chelates, providing insight into sol-gel process advancement, have been successfully monitored via 1H NMR, 13C NMR, and FTIR spectroscopy. It has been established that Al(OBus)3 and Ti(OBun)4 react completely with Eaa, forming chelates after 1 h, while after 24 h hydrolysis is already advanced. Hydrolysis is accelerated in the presence of Zn(NO2)3·6H2O, supplying the water needed for hydrolysis. In dried gels, the amount of ethyl acetoacetate is greatly reduced, and it is mainly present unbound. According to XRD analysis, samples with none or less titania are composed of layered double hydroxide, while in samples with greater amounts of titania, crystal nitrates are present. In all samples except those without Al, the spinel phase with variable composition crystallizes. [ABSTRACT FROM AUTHOR]

A fast and environmentally benign procedure for the preparing of polyhydroquinolines using graphene quantum dots immobilized papain as an efficient catalyst was introduced. Papain, as a suitable known catalyst in organic synthetic chemistry, was immobilized onto nitrogen graphene quantum dots and used as a very powerful heterogeneous catalyst for the MW-assisted synthesis of various polyhydroquinoline derivatives. The Fourier transform infrared spectroscopy, X-ray diffraction pattern, scanning electron microscopy, and field emission scanning electron microscopy analysis were used for the characterization of the structure of newly prepared catalyst. These important organic compounds were prepared through the four-component fusion of dimedone, ethyl acetoacetate, and ammonia with different chosen arylaldehydes, under rapid, simple, and mild solvent-free conditions. This protocol offers some interesting benefits such as excellent yields (98–100%), very easy handling, simple workup procedure, economy, cleaner reaction profile, and shorter reaction times (2–3 min). All the products were characterized with 1H-NMR, 13C-NMR, and FT‐IR spectroscopy techniques. [ABSTRACT FROM AUTHOR]

This article explores the use of melamine as a catalyst for synthesizing dihydropyrano[2,3-c]pyrazole derivatives. The authors compare melamine to other catalysts and emphasize its benefits of being reusable, readily available, and cost-effective. The article provides a detailed procedure for the synthesis and notes that the melamine catalyst can be recycled multiple times without significant decreases in product yields. The authors also suggest that melamine may have potential applications in the synthesis of other heterocycles. [Extracted from the article]

This article explores the use of uric acid as a catalyst for synthesizing important heterocyclic compounds. The researchers optimized the reaction conditions and found that uric acid was an effective catalyst, producing desired products in good to excellent yields. The study highlights the potential of uric acid as a natural and reusable catalyst for synthesizing biologically significant compounds. The article provides detailed tables summarizing the reaction conditions and yields, and the experimental section offers information on the synthesis process and compound characterization. The study was supported by the Research Council of the University of Sistan and Baluchestan. [Extracted from the article]

Recent Synthesis of Mono‐ & Bis‐Pyranopyrazole Derivatives. Pyranopyrazole is an important structural unit in heterocyclic chemistry and is useful in pharmaceutical and agrochemical industries. The pyranopyrazole‐based compounds are known in the agricultural industry as herbicides, fungicides, and insecticide agents and in medicinal fields as antimicrobial, anticancer, and antiHIV agents. Despite its wide range of applications, the synthesis of pyranopyrazole has several limitations such as the cost of reagents, potential environmental risks, harsh reaction conditions, longer reaction times, laborious workup procedures, and unsatisfactory yields. However, many studies have been recently reported on the synthesis of pyranopyrazoles using mild, green, and environmentally friendly methods that also give higher yields. Different catalysts and conditions have been reported for the synthesis of pyranopyrazole using four, three, and two components. Among these, four‐component synthesis is commonly reported by using benzaldehyde, hydrazine derivatives, ethyl acetoacetate and malononitrile due to the commercial availability and stability of the reagents. This review summarized the recent synthesis of pyranopyrazole i. e., mono‐ and bis‐pyranopyrazole derivatives via four‐, three‐ and two‐component‐based reactions. Mono‐ and bis‐pyranopyrazole derivatives varied due to the number of pyranopyrazole units that contributed to play an important role in increasing the binding interaction and biological activities beneficial for pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The esters of substituted 1,4-dihydropyirdines (1,4-DHP) are formed in the reaction of an appropriate aldehyde and ethyl acetoacetate in the presence of concentrated water solution of ammonia. The esters form the amides by the reaction with primary amines. The series of the amides has been synthesized with the aim to analyze their chemical characteristics, antioxidant and antimicrobial activity. The amine used in this research is 2-aminothiazole. The antioxidant activity is analysed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) methods and the antimicrobial activity screening was performed by broth microdilution method, using different microbial strains. The characterization of the obtained amides was done by melting points, FTIR, NMR and elemental analysis. The possibilities for further research was suggested, which could lead to the application of selected compounds. [ABSTRACT FROM AUTHOR]

Inulin, a natural polysaccharide has been utilized as a novel biodegradable, efficient, and environmentally benign catalyst for the ultrasound‐assisted one‐pot, single‐step multicomponent formation of a library of pyrazolopyrano[2,3‐d]pyrimidine‐diones 5(a‐k) from the reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehydes, and barbituric/ thiobarbituric acid in aqueous ethanol (1 : 1) at 50 °C. This facile methodology offers a metal‐free, sustainable, selective synthesis of pyrazolopyrano[2,3‐d]pyrimidine‐diones with no by‐product having excellent product yield (≥90 %) in a shorter reaction time. Additionally, the biocompatible inulin is recyclable for up to five consecutive runs without much decrease in its catalytic potential. Inulin has been characterized by spectral techniques such as XRD, FTIR, Raman, and SEM. It shows remarkable stability in the reaction medium as evident from the zeta potential value of −21.39 mV and hydrodynamic diameter of 459.5 nm. Novel pyrazolopyrano[2,3‐d]pyrimidine‐diones (5g, 5h, 5j, and 5k) were also synthesized using this protocol and the synthesized compounds were examined for their antimicrobial activity. [ABSTRACT FROM AUTHOR]

This article discusses a new method for synthesizing homoallylic diene halides, which are important compounds used in the preparation of the taxane A-ring system. Taxol, a compound with anticancer properties, has been synthesized using various methods, including a type II intramolecular Diels-Alder reaction. The authors of this article report a new synthesis method for homoallylic halides, which are important precursors for the taxane ring system. The synthesis of these compounds was achieved using readily available and inexpensive starting materials, and the reactions are potentially scalable for large-scale production. The article provides technical information about the synthesis and characterization of various chemical compounds, including data such as nuclear magnetic resonance (NMR) spectra, mass spectrometry (MS) results, and experimental procedures. The authors acknowledge Prof. Joaquín Tamariz for HRMS analysis, and supporting information for the article is available online. [Extracted from the article]

The reaction of (1,2-dibromoethyl)(diphenyl)phosphine oxide with CH-acids (acetylacetone, acetoacetic ester, and malonic ester) in the presence of sodium hydroxide has afforded diphenylphosphoryl-substituted cyclopropanes in high yield. It has been shown that the reaction of (1,2-dibromoethyl)(diphenyl)phosphine oxide with primary arylamines leads to the formation of bis(phosphine oxides), in contrast to alkylamines which lead to phosphoryl-substituted aziridines. [ABSTRACT FROM AUTHOR]

This article provides a review of recent advances in the synthesis and biological activities of functionalized pyrimidines. It discusses the synthesis and pharmacological activities of pyrimidines in the areas of anticancer, antidiabetes, and antioxidant properties. The article also highlights the potential applications of novel pyrimidine compounds in various fields, including their antioxidant, anti-inflammatory, antibacterial, and antiviral activities. The authors acknowledge the support of Mohanlal Sukhadia University in India. [Extracted from the article]

This document discusses the synthesis and characterization of novel cyclopenta[b]indole derivatives and their potential biological activities. The compounds were synthesized using a simple method and their structures were determined through analysis. The document provides information on the antibacterial and antioxidant activities of the compounds, as well as their drug-likeness. The authors hope that these compounds will inspire further research in this area. The document also acknowledges the institutions that supported the study. [Extracted from the article]

The eco-friendly techniques were utilized for the straightforward synthesis of new heterocyclic compounds bearing the sulfadiazine moiety by employing ultrasound irradiation techniques. Initially, sulfadiazine (1) was subjected to diazotization, followed by a coupling reaction with an activated methylene group (ethyl acetoacetate) to yield a hydrazone compound (3). Subsequently, the coupling adducts (3) were reacted with ethyl benzoylacetate, benzyl hydrazine, thiosemicarbazide, and guanidine under ultrasound irradiation, leading to the formation of pyridazine (4), pyrazolines (5, 6), and pyrimidine (7), respectively. Furthermore, when pyrazoline compound (6) was treated with chloroacetone and bromoaceophenone under ultrasound conditions, thiazole compounds (6a) and (6b) were formed, respectively. Additionally, new derivatives (10) and (11) were synthesized through diazotizing compound (7), followed by coupling reactions with an activated methylene group (acetylacetone) and reactions with urea and thiourea, respectively, all under ultrasound conditions. All the synthesized compounds were characterized using spectroscopic techniques such as FT IR, ¹H-NMR, and 13C-NMR spectra. The synthesized chemicals exhibited promising antimicrobial activities against human pathogenic bacteria strains (Escherichia coli and Staphylococcus aureus) and Candida albicans fungi, as assessed through the broth microdilution technique. [ABSTRACT FROM AUTHOR]

A selective reaction of bridged ozonides with Fe(II) salts proceeds through the sequence of O−O, C−C scissions and halogenation to form α‐halogen substituted δ‐ketoesters and δ‐diketones in 15–72% yields. The overall sequence shows how a temporary installation of a peroxide functionality can be used to replace the acyl group within an acetoacetic ester unit with a halogen. [ABSTRACT FROM AUTHOR]

The Hantzsch reaction created a new series comprising 1,4-dihydropyridine pyrazoles and oxa diazoles (DHP) by initially synthesizing DHP esters, then its carbohydrates, and subsequent treatment with hydrazine. Pyrazole derivatives (Am1 and Am2) were obtained via the reaction of hydrazines with acetylacetone or ethyl acetoacetate, whereas the oxadiazole derivative (Am3) was prepared via reaction with carbon disulfide in an alkaline medium. The prepared compounds were identified using spectroscopic techniques (FTIR, ¹H and 13C NMR, and mass spectrometry). The anti-breast cancer activity of new compounds was evaluated. This cytotoxicity activity afforded that compound (AS) was the strongest in this group together with an IC50 = 100.24µg mL-1, whereas compound (AT) demonstrated the lowest potency, with an IC50 value of 300 µg mL-1. The Hantzsch reaction was used in the synthesis of a new 1,4-dihydropyridine that has pyrazole and oxadiazole moieties. The activity of in vitro cytotoxicity (MTT cell viability assay) was determined. In vitro MCF7 cells were used in the evaluation of the cytotoxicity activity (MTT cell viability assay) of new compounds. This cytotoxicity activity meant that compound (AS) was the strongest in this group, with an IC50 of 100.24 µg mL-1, while compound (AT) had the least potency, with an IC50 value of 300 µg mL-1. Based on our findings, we can infer that 1,4-dihydropyridine derivatives (DHPs) are noteworthy heterocyclic compounds with pharmacological potential.  This cytotoxicity activity meant that compound (AS) was the strongest in this group, with an IC50 of 100.24 µg mL-1, while compound (AT) had the least potency, with an IC50 value of 300 µg mL-1.  [ABSTRACT FROM AUTHOR]