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ABSTRACT The syntheses and bioevaluation of 3‐acyl‐2‐pyridones have garnered significant interest in recent years as a novel class of compounds with diverse biological activities. The bioactivities cover a wide range of therapeutic areas including antimicrobial, antitumor, anti‐inflammatory, antifungal, antibiotic, neuritogenic, cytotoxic, and antiviral activities. Therefore, 3‐acyl‐2‐pyridone scaffold offers a versatile platform for the development of new molecules with potential applications in medicinal chemistry. The recent exploration on synthesis and bioevaluation of 3‐acyl‐2‐pyridones has yielded promising results, making them attractive targets for further optimization and development of new therapeutic agents. This review summarizes the available information on total synthesis of 3‐acyl‐2‐pyridone containing natural products, and the other synthetic strategies developed for accessing the 3‐acyl pyridones such as multicomponent synthesis, condensation reaction, microwave‐assisted synthesis, catalytic hydrogenation reactions, metalation reaction, Michael addition, and formylation reactions. The presented information may serve as a valuable resource for researchers working in the field of medicinal chemistry and drug discovery, stimulating further exploration and development of this intriguing scaffold. [ABSTRACT FROM AUTHOR]

In the present study a library of five (2‐(amino)‐1,3‐thiazin‐6‐one) compounds was synthesized and investigated as against glioblastoma cells in vitro and in vivo in the mice model. The results revealed that all of the five 1,3‐thiazin‐6‐one compounds (4a, 4b, 4c, 4d and 4e) exhibited cytotoxicity against U87MG and 9 L brain cancer cell lines. Moreover, it was found that 9 L cells showed slightly higher sensitivity towards the compounds 4a, 4b, 4c, 4d and 4e compared to U87MG cells. It was observed that the compounds 4a, 4b, 4c, 4d and 4e showed a time‐dependent increase in uptake efficiency by U87MG and 9 L cells. Furthermore, the data revealed that uptake of the compounds and therefore internalization was maximum during initial 1 h of the treatment. Among the synthesized compounds, compound 4c containing trifluoromethyl moiety showed higher uptake efficiency compared to the compound 4a, 4b, 4d and 4e. Treatment of U87MG and 9 L cell tumor spheroids with compound 4c significantly (P<0.05) inhibited the tumor growth compared to the control spheroids. In vivo data revealed that treatment with compound 4c led to a significant (P<0.05) decrease in glioblastoma growth in mice in dose‐dependent manner. Growth of glioblastoma in mice was almost completely inhibited after 28 days of treatment with 2 mg/kg dose of compound 4c. Pharmacokinetic studies showed that compound 4c remained in circulation for longer duration in mice and its terminal half‐life was found to be 6.5 h. Treatment of U87MG and 9 L cells with compound 4c led to a prominent decrease in expression of CYR61 protein. In conclusion, findings of the present study suggest that compound 4c acts as a potential therapeutic agent for the treatment of advanced brain cancer through activation of Hippo pathway. Therefore, more studies need to be performed to investigate the detailed mechanism underlying the inhibitory effect of compound 4c against the glioblastoma. [ABSTRACT FROM AUTHOR]

Targeted radionuclide therapy (TRT) is an effective treatment for tumors. Self-condensation strategies can enhance the retention of radionuclides in tumors and enhance the anti-tumor effect. Considering legumain is overexpressed in multiple types of human cancers, a 131I-labeled radiopharmaceutical ([ 131 I]MAAN) based on the self-condensation reaction between 2-cyanobenzothiazole (CBT) and cysteine (Cys) was developed by us recently for treating legumain-overexpressed tumors. However, liver enrichment limits its application. In this study, a new radiopharmaceutical [ 131 I]IM(HE) 3 AAN was designed and synthesized by introducing a hydrophilic peptide sequence His-Glu-His-Glu-His-Glu ((HE) 3) into [ 131 I]MAAN to optimize the pharmacokinetics. Upon activation by legumain under a reducing environment, hydrophilic [ 131 I]IM(HE) 3 AAN could react with its precursor to form heterologous dimer [ 131 I]H-Dimer that is highly hydrophobic. Cerenkov imaging revealed that [ 131 I]IM(HE) 3 AAN displayed superior tumor selectivity and longer tumor retention time as compared with [ 131 I]MAAN , with a significant reduction in the liver uptake. After an 18-day treatment with [ 131 I]IM(HE) 3 AAN , the tumor proliferation was obviously inhibited, while no obvious injury was observed in the normal organs. These findings suggest that [ 131 I]IM(HE) 3 AAN could serve as a promising drug candidate for treating legumain-overexpressed tumors. [Display omitted] [ABSTRACT FROM AUTHOR]

An approach for the preparation and stabilization of primary phosphine oxides is presented complementing previous methods of in situ generation. Specifically, RP(O)H2 where R=benzyl (Bn), cyclohexyl (Cy), 2‐naphthyl (2‐Naph), phenyl (Ph), tert‐butyl (t‐Bu) was prepared by controlled oxidation of the corresponding primary phosphine in presence of ferrocene as stabilizing reagent. The primary phosphine oxides were characterized using NMR and MS and studied in twofold hydrophosphorylation of diketones. The domino‐phospha‐aldol reaction catalysed with 5 mol% of sodium methoxide yielded five‐, six‐ and seven‐membered heterocyclic tertiary phosphine oxides with a high degree of stereoselectivity, as confirmed by single X‐ray diffraction. [ABSTRACT FROM AUTHOR]

By using amino sulfonic acid salts, formaldehyde, and glyoxal as starting materials, an optimized synthesis process for 2,4,6, 8-tetrachitro-2,4,6, 8-tetraazabicyclic [3.3.0] octane(BCHMX) without purification of the intermediate (2,4, 6,8-tetraazabicyclo[3. 3.0]octane sulfonate) was developed. The molecular structure, crystal structure, and thermal stability of the target product were analyzed and characterized using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), carbon-13 nuclear magnetic resonance spectroscopy (13C NMR), and thermo-gravimetric analysis combined with differential scanning calorimetry (TC-DSC). Results show that, the optimal process conditions are as follows: 1. 07 mole of potassium amino sulfonate per mole of formaldehyde, 1. 77 mole of glyoxal, 8.4 mole of water as the solvent, and 0. 023 mole of formic acid as the acid catalyst. The condensation reaction is carried out for 12 hours. The nitration reaction is performed using fuming nitric acid and acetic anhydride in a molar ratio of 1. 3 ' 1 as nitrating agent at 40°C . By the condensation and nitration reactions, BCHMX with a purity of 97.8% is obtained with a total yield of 65. 29% . BCHMX belongs to the monoclinic crystal system with space group of P2(1)/c, and the theraml decomposition temperature is 223 °C . [ABSTRACT FROM AUTHOR]

Hydrocarboxylation of methyl 2‐octynoate, a chemical commercially available at a low cost, with N‐protected amino acids was developed with a gold‐zinc cooperative catalyst constructed with a 5‐[(2,2′‐bipyridin)‐5‐yl]imidazo[1,5‐a]pyridin‐3‐ylidene to prepare α‐methoxycarbonyl enol esters as acylating reagents. The α‐methoxycarbonyl enol esters were isolable through silica‐gel column chromatography and storable without precautions regarding moisture. Acylation of free amines with the α‐methoxycarbonyl enol esters proceeded without epimerization of the stereogenic center derived from the enol esters, affording analytically pure dipeptide compounds through filtration and hexane‐washing. [ABSTRACT FROM AUTHOR]

A combination of swelling in imidazolium ionic liquids and beta-irradiation – both common pretreatments in biomass processing on their own – leads to unexpected effects, with beta-irradiation causing degradation of the pure ionic liquid and also modification of cellulose suspended in the ionic liquid. The underlying chemistry was investigated in a series of model compound experiments. Here, we report that beta-irradiation of the ionic liquid EMIM-OAc containing equimolar amounts of benzaldehyde and d-glucose affords an unexpected condensation product C17H20O7, of which the structure was elucidated as 5-[(1S,2R,3R)-1,2,3,4-tetrahydroxybutyl]-2-phenyl-3-furoic acid, applying a combination of analytical techniques, mainly NMR spectroscopy, after conversion into the ethyl ester derivative for purification. No reaction at all occurred without beta-irradiation under otherwise identical conditions. Intriguingly, the acetate – the IL´s anion – was incorporated into the condensation product, which can formally be regarded as the condensation product of benzoylacetic acid (from benzaldehyde and the IL´s acetate) and d-glucose. The reaction occurred only when all three components – acetate-type IL, glucose and PhCHO – were irradiated simultaneously. The structure elucidation of the compound is presented, along with a discussion of possible formation mechanisms. Future experiments need to address the generality of the reaction for conversion of other aldehydes and aldoses, and the question of whether a similar process occurs with the reducing end of celluloses or other polysaccharides. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are typical porous organic polymers with crystalline porous architectures, which are provided with the merits of high surface area, low density, and high structural as well as functional adjustability. In comparison to conventional COFs with single-stranded linkages, ladder-type COFs are a very unique class of COFs which are usually connected by rings (conjugated or non-conjugated). Given the structural characteristics of ladder-type COFs, they overcome the shortcomings of conventional COFs and possess the advantages of rigid backbone, extended π-conjugation length, extraordinary chemical/thermal stability, and high conductivity. However, compared to the well-investigated conventional COFs, ladder-type COFs are paid little attention. Gaining ladder-type COFs quickly and efficiently encounters great challenges. Ladder-type COFs, containing a wide array of structures and functionalities, have recently come into focus. Especially for energy conversion and storage, they show great potential with excellent performances. Accordingly, this article systematically summarizes the recent developments in constructing ladder-type COFs. Initially, the topology design is generally introduced. Subsequently, the synthesis of ladder-type COFs is discussed in detail. It shows how to rationally select organic reactions and monomers and how to manipulate experimental conditions to construct ladder-type COFs bearing different functional groups and different conjugation lengths. Ultimately, this paper offers a concise outlook on the prospective advancements in the synthesis of ladder-type COFs.

Fabrication of ceramic bodies with complex structures via photopolymerization-based 3D printing with minimal deformation during the inevitable heat treatment necessitates the development of a photopolymerizable ceramic slurry. This study prepared a photocurable slurry using a photocurable resin and particles coated with an inorganic binder. The condensation efficiency of the inorganic binder was improved by applying an aging process to the green bodies, which in turn improved the fracture strength and enhanced the glass conversion efficiency of the particles during the subsequent firing process. The exceptional mechanical properties of the fired bodies fabricated using inorganic binder-coated starting particles can be attributed to the glass matrix formed between the particles rather than the particle-to-particle interfaces. We believe this study demonstrates the feasibility of fabricating ceramic bodies with minimal shrinkage and distortion compared to conventionally sintered bodies. • A photopolymerizable ceramic slurry using inorganic binder-coated particles was developed. • The aging process promoted siloxane bonding and vitrification, which improved the fracture strength. • Excellent mechanical properties are achieved due to the glass matrix formed between the particles. • Shrinkage and distortion are minimized, demonstrating the potential for complex 3D printed ceramics. [ABSTRACT FROM AUTHOR]

Over the last few years, benzimidazole-heterocycle hybrid compounds have received considerable attention due to the wide spectrum of their biological property and many important chemical and pharmacological applications. These compounds have revealed antibacterial, antimicrobial, anticoagulant, antidiabetic and other activities, and they have been used as drugs in the market to treat several diseases. Furthermore, hybrid heterocyclic compounds possessing a benzimidazole skeleton exhibit significant complexing and anticorrosive properties. All of these applications have favored the development of a large number of synthetic strategies to prepare these heterocyclic systems in different reaction conditions. Many research articles on the synthesis of benzimidazole-heterocycle hybrid compounds have been reported in the literature. In this review, we present and discuss the synthetic routes of several benzimidazole-heterocycle hybrid compounds. [ABSTRACT FROM AUTHOR]

Abstract Schiff bases are a diverse group of organic compounds with great pharmaceutical importance due to the presence of carbon–nitrogen double bonds (–C=N–). These compounds are synthesized by the condensation reaction between a primary amine and an aldehyde or ketone in a suitable solvent such as methanol. These compounds have shown antibacterial, antifungal, antiviral, anti-inflammatory, and antioxidant activities, which have garnered the attention of organic chemists in synthesizing these compounds. Recent advances have been summarized in this review paper mainly including compounds with potential antibacterial, antifungal, and antiviral activities. Synthetic schemes are included to provide a better understanding of the Schiff base synthesis mechanism. This review paper will provide a way forward for the pharmaceutical chemist to synthesize new compounds with potential biological activities. Graphical abstract

Anabolic metabolism of carbon in mammals is mediated via the one- and two-carbon carriers S-adenosyl methionine and acetyl-coenzyme A. In contrast, anabolic metabolism of three-carbon units via propionate has not been shown to extensively occur. Mammals are primarily thought to oxidize the three-carbon short chain fatty acid propionate by shunting propionyl-CoA to succinyl-CoA for entry into the TCA cycle. Here, we found that this may not be absolute as, in mammals, one nonoxidative fate of propionyl-CoA is to condense to two three-carbon units into a six-carbon trans-2-methyl-2-pentenoyl-CoA (2M2PE-CoA). We confirmed this reaction pathway using purified protein extracts provided limited substrates and verified the product via LC-MS using a synthetic standard. In whole-body in vivo stable isotope tracing following infusion of 13C-labeled valine at steady state, 2M2PE-CoA was found to form via propionyl-CoA in multiple murine tissues, including heart, kidney, and to a lesser degree, in brown adipose tissue, liver, and tibialis anterior muscle. Using ex vivo isotope tracing, we found that 2M2PE-CoA also formed in human myocardial tissue incubated with propionate to a limited extent. While the complete enzymology of this pathway remains to be elucidated, these results confirm the in vivo existence of at least one anabolic three- to six-carbon reaction conserved in humans and mice that utilizes propionate.

Ester compounds, widely found in pharmaceutical and natural products, play a crucial role in organic synthesis, prompting the development of numerous methods for their synthesis. An important chemical approach in synthesizing esters from carboxylic acids involves the activation of the carboxyl function, requiring the conversion of the hydroxyl group into a suitable leaving group. This paper presents the findings of our investigations into an efficient method for producing esters from carboxylic acids and alcohols, using the Lewis acid titanium tetrachloride. Titanium tetrachloride has proven highly effective as a coupling reagent for the one-pot formation of esters from carboxylic acids and alcohols operating under mild and neutral conditions. Notably, the reaction eliminates the need for bases, yielding carboxylic esters in high purity and yields. The method is efficient, even with long-chain carboxylic acids, and operates well with primary alcohols in dichloromethane. Steric hindrance, potentially present in carboxylic acids, has a moderate effect on the reaction. Alcohol substrates that easily form stable carbocations require, instead, the use of non-polar solvents like hexane for the reaction. [ABSTRACT FROM AUTHOR]

A convenient and efficient method for the synthesis of benzimidazoles, and benzothiazoles have been developed using recyclable magnetite polydopamine-supported copper nanoparticles (Fe3O4@PDA/CuCl2) under green and mild conditions. This catalytic system enables the one-pot synthesis of benzazoles by employing available, and easy to-handle aldehydes and o-phenylenediamine/o-aminothiophenol. Utilizing sustainable and mild conditions, a variety of functionalized benzazoles has been prepared in nearly quantitative yields (79–97%) within 5–30 min at 40 °C. The method offers advantages such as high yield, short reaction time, use of air as oxidant, ease of workup, avoiding toxic organic solvents, and a simple workup protocol. The catalyst could be recycled and reused up to five times without any loss of significant catalytic activity. The catalyst's great effectiveness can be seen in the fact that the TON reaches 2633–3233 and the TOF reaches 5266–38,800 h−1. [ABSTRACT FROM AUTHOR]

The chemistry of 3-acetylquinoline has attracted increased attention in both synthetic organic and medicinal chemistry. The present review summarizes the published data on the synthesis of 3-acetylquinoline derivatives and their reactions, including reactions involving and not involving the acetyl group. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the largest concerns to global health in recent decades has been identified as the growth of bacteria resistance to antibiotics. The Schiff base (SBs) and the zinc(II) SBs complex compounds category have attracted a lot of interest because of their function in chemical syntheses and their potential for bioactive and pharmacological effects. The present study includes the synthesis of various SBs with different substituents. Equimolar mixtures of benzaldehyde derivatives (1, 2) and aniline derivatives (3, 4) are used to carry out a series of condensation reactions to get compounds (5-7). By stoichiometrically combining Zn (II) acetate and ZnCl2 separately with the SBs ligand (7) in ethanol, it has been possible to prepare the SBs zinc(II) complex (8). The structure of the ligand and its metal complex are analyzed using (Fouriertransform infrared spectroscopy, 1H-NMR, 13C-NMR) spectroscopy, scanning electron microscopy, and liquid chromatography–mass spectrometry. Moreover, the synthesized compounds are verified in vitro against Escherichia coli Gram negative, Staphylococcus aureus Gram positive, and fungi (Candida albicans). Compounds (5, 7, and 8) indicated significant growth inhibition against E. coli Gram negative and fungi (C. albicans) with different inhibition zones starting from 7 to 17.5 mm. [ABSTRACT FROM AUTHOR]

The organic compound category known as azomethine oxides has garnered significant attention due to its potential for bioactive and pharmacological effects, as well as its role in organic syntheses. Existing literature offers various methods for producing derivatives of these compounds. This study, in particular, concentrates on the creation of several aromatic oximes through the reduction of corresponding aldehydes. Furthermore, these oximes are employed in the generation of new azomethine oxides through a condensation reaction with selected aldehydes. The molecular structure of the synthesized azomethine oxides is determined using techniques such as Fourier-transform infrared spectroscopy, ¹H-NMR, and 13C-NMR. Finally, the antimicrobial effectiveness of these compounds was assessed against Escherichia coli (gram-negative bacteria), Staphylococcus aureus (gram-positive bacteria), and Candida albicans (fungus). The synthesized compounds were obtained with high purity and yielded excellent results. Furthermore, the data demonstrates that these azomethine oxides exhibit significant antimicrobial activity when compared to standard drugs. [ABSTRACT FROM AUTHOR]

The solvent-free condensation reaction of various aliphatic aldehydes, cycloalkanones, and benzaldehydes with rhodanines catalyzed by Amberlyst 26 has been reported. The catalyst's efficiency, simple work-up, simple recycling procedure, and high catalyst recyclability without any considerable change of yields several times were found to be interesting. Furthermore, the drastic acceleration of ultrasound irradiation was realized to be efficient for the formation of alkylidenerhodanine, cycloalkylidene-rhodanine, and arylidenerhodanine in moderate to good yields within a short time. [ABSTRACT FROM AUTHOR]

One of the largest concerns to global health in recent decades has been identified as the growth of bacteria resistance to antibiotics. The Schiff base (SBs) and the zinc(II) SBs complex compounds category have attracted a lot of interest because of their function in chemical syntheses and their potential for bioactive and pharmacological effects. The present study includes the synthesis of various SBs with different substituents. Equimolar mixtures of benzaldehyde derivatives (1, 2) and aniline derivatives (3, 4) are used to carry out a series of condensation reactions to get compounds (5-7). By stoichiometrically combining Zn (II) acetate and ZnCl2 separately with the SBs ligand (7) in ethanol, it has been possible to prepare the SBs zinc(II) complex (8). The structure of the ligand and its metal complex are analyzed using (Fourier transform infrared spectroscopy, 1H-NMR, 13C-NMR) spectroscopy, scanning electron microscopy, and liquid chromatography–mass spectrometry. Moreover, the synthesized compounds are verified in vitro against Escherichia coli Gram negative, Staphylococcus aureus Gram positive, and fungi (Candida albicans). Compounds (5, 7, and 8) indicated significant growth inhibition against E. coli Gram negative and fungi (C. albicans) with different inhibition zones starting from 7 to 17.5 mm.

The organic compound category known as azomethine oxides has garnered significant attention due to its potential for bioactive and pharmacological effects, as well as its role in organic syntheses. Existing literature offers various methods for producing derivatives of these compounds. This study, in particular, concentrates on the creation of several aromatic oximes through the reduction of corresponding aldehydes. Furthermore, these oximes are employed in the generation of new azomethine oxides through a condensation reaction with selected aldehydes. The molecular structure of the synthesized azomethine oxides is determined using techniques such as Fourier-transform infrared spectroscopy, 1H-NMR, and 13C-NMR. Finally, the antimicrobial effectiveness of these compounds was assessed against Escherichia coli (gram-negative bacteria), Staphylococcus aureus (gram-positive bacteria), and Candida albicans (fungus). The synthesized compounds were obtained with high purity and yielded excellent results. Furthermore, the data demonstrates that these azomethine oxides exhibit significant antimicrobial activity when compared to standard drugs.

Xanthones comprise a large family of heterocycles displaying fascinating biological properties. Many synthetic protocols have been developed for the preparation of natural and nonnatural xanthone derivatives. Among them, condensation reactions between salicylic acid derivatives and phenol partners are highly desirable. Those reactions can be satisfactorily performed using Eaton's reagent (P2O5 in CH3SO3H). Despite being highly effective with a variety of substrates, this approach presents limitations that depend on the electronic nature of the reaction precursors. The scope and limitations of the Eaton's reagent-mediated preparation of xanthones are herein presented and discussed. In short, this approach is limited to the utilization of very electron-rich phenol substrates (like phloroglucinol compounds), or to electron-rich phenol precursors (like resorcinol derivatives) via the isolation of benzophenone intermediates in this latter case. Electron-poor phenols are not amenable to this transformation with Eaton's reagent. [ABSTRACT FROM AUTHOR]

An efficient synthesis of optically pure macrocyclic mono- and binuclear polylactones has been proposed. The synthesis is based on the condensation of natural triol, castor oil, with sebacoyl dichloride in 1 : 1 or 1 : 2 ratios in boiling carbon tetrachloride in the presence of triethylamine and N,N-dimethylaminopyridine as a catalyst. [ABSTRACT FROM AUTHOR]

The reaction of alicyclic oximes and dioximes with epichlorohydrin in the presence of a BF3O(C2H5)2 catalyst to obtain chlorohydrin ethers of the corresponding dioximes was studied. A probable mechanism for the reaction is proposed. Epoxy ethers of dioximes were synthesized by dehydrochlorination of chlorohydrin ethers with alkali. The physico-chemical parameters of the synthesized compounds were determined. The composition and structure of chlorohydrin and epoxy ethers were proven by ¹H, 13C NMR, IR-spectroscopy and the hydroxyl, chlorine and epoxy numbers of the synthesized compounds were determined. The synthesized epoxy compounds can be used as synthetic fibers in the textile industry. [ABSTRACT FROM AUTHOR]

The Z-scan instrument was used to study the nonlinear optical (NLO) properties of the derivatives of 3,3′-biindole 2,2′(1H,1′H)-dione, with different substitutions such as bromine, methyl, and phenyl groups. Specifically, the nonlinear absorption coefficient, β, nonlinear refraction index, n 2 , have been extracted and reverse saturation absorption and self-defocusing phenomena were investigated. It is observed that the presence of bromine in the compound structure can reduce the NLO properties. The reduction of dipole moment with bromine substitutions in the compound structure was confirmed with the quantum calculation. The NLO properties of the biindole derivatives related to the thermo-optic coefficient and dipole moment of the compound. Overall, our findings indicate that the biindole derivatives are promising candidates for NLO absorption materials. [ABSTRACT FROM AUTHOR]

Two-dimensional covalent organic frameworks (2D COFs) are ideal heterogeneous catalysts, and have been widely used in photocatalysis and electrocatalysis, owing to their high specific surface area, tunable porosity, facile functionalization, highly accessible and dispersed catalytic active sites. Starting from the rational design strategy of the structure and functionalization of COFs, synthetic methods for 2D COFs were reviewed, including solvothermal synthesis, mechanochemical synthesis, microwave synthesis, ionothermal synthesis, sonochemical synthesis, interfacial synthesis, and room temperature synthesis. Furthermore, recent progress of 2D COFs applications in photocatalysis and electrocatalysis was summarized, including hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, and photo/electrocatalytic organic conversion. Finally, the challenges of 2D COFs in photocatalysis and electrocatalysis were summarized, including high cost of organic ligands, difficulty of industrialization, the use of sacrificial agents, and a cooperative coupling reaction strategy was proposed based on photo/electroorganic synthesis and hydrogen evolution or oxygen evolution reactions.

This work focuses on porous organic polymers (POPs), which have gained significant global attention for their potential in energy storage and carbon dioxide (CO2) capture. The study introduces the development of two novel porous organic polymers, namely FEC-Mel and FEC-PBDT POPs, constructed using a simple method based on the ferrocene unit (FEC) combined with melamine (Mel) and 6,6′-(1,4-phenylene)bis(1,3,5-triazine-2,4-diamine) (PBDT). The synthesis involved the condensation reaction between ferrocenecarboxaldehyde monomer (FEC-CHO) and the respective aryl amines. Several analytical methods were employed to investigate the physical characteristics, chemical structure, morphology, and potential applications of these porous materials. Through thermogravimetric analysis (TGA), it was observed that both FEC-Mel and FEC-PBDT POPs exhibited exceptional thermal stability. FEC-Mel POP displayed a higher surface area and porosity, measuring 556 m2 g−1 and 1.26 cm3 g−1, respectively. These FEC-POPs possess large surface areas, making them promising materials for applications such as supercapacitor (SC) electrodes and gas adsorption. With 82 F g−1 of specific capacitance at 0.5 A g−1, the FEC-PBDT POP electrode has exceptional electrochemical characteristics. In addition, the FEC-Mel POP showed remarkable CO2 absorption capabilities, with 1.34 and 1.75 mmol g−1 (determined at 298 and 273 K; respectively). The potential of the FEC-POPs created in this work for CO2 capacity and electrical testing are highlighted by these results. [ABSTRACT FROM AUTHOR]

In order to study the synergistic effect of imidazole based ionic liquids in nitric acid, the coal samples were firstly treated with nitric acid(HNO3) solution, 1-butyl-3-methylimidazoletetrafluoroborate([Bmim][BF4]) solution and its mixed solution respectively. Then the wettability of each solution was tested by contact angle experiment. Finally, the pore-crack damage of coal samples after each solution treatment was observed by scanning electron microscope experiment. The results found that single solution and composite solution have a great influence on the wettability and pore structure of coal samples, and the synergistic effect of composite solution increases the oxygen-containing functional groups in coal and makes the aromatic structure of coal samples more compact. This result is the same as the experimental result of contact angle, and the contact angle of coal dust in composite solution is the smallest. In addition, through the observation of coal sample surface by scanning electron microscope, it is found that the seepage network channel of coal sample under the synergistic effect is more developed than that of coal sample treated with single solution. In the engineering practice of Yuwu Coal Mine, the gas volume fraction of the borehole is increased by more than 20%, the gas flow rate increased by more than one times.

A metal‐free, straightforward, non‐hazardous reagent‐added, one‐pot approach for the efficient synthesis of 2‐arylimino‐2H‐chromenes with high yields was developed for the first time in this report through the coupling of salicylaldehydes with β‐ketothioamides, which was catalyzed by lipase in water. This green strategy provides an efficient method to obtain various 2‐arylimino‐2H‐chromenes and enriches the practical application of biocatalysis. [ABSTRACT FROM AUTHOR]

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The effectiveness of corrosion inhibition based on the organic compound 2,7-dimethyl-2,7-dicyanide-3,6-diazaoctan (MAD-20) was studied on low-carbon steel in 15% H2SO4 solution. The samples were exposed in a 15% H2SO4 solution without an inhibitor and with different concentrations of MAD-20 inhibitors. Weight loss measurements, scanning electron microscope (SEM) were used to study the inhibitory effects of MAD-20. It has been shown that the MAD-20 inhibitor is an effective inhibitor of acid corrosion. [ABSTRACT FROM AUTHOR]

Two aminobenzoic acid based crystalline imines (HMBA and DHBA) were synthesized through a condensation reaction of 4-aminobenzoic acid and substituted benzaldehydes. Single-crystal X-ray diffraction was employed for the determination of structures of prepared Schiff bases. The stability of super molecular structures of both molecules was achieved by intramolecular H-bonding accompanied by strong, as well as comparatively weak, intermolecular attractive forces. The comparative analysis of the non-covalent forces in HMBA and DHBA was performed by Hirshfeld surface analysis and an interaction energy study between the molecular pairs. Along with the synthesis, quantum chemical calculations were also accomplished at M06/6-311G (d, p) functional of density functional theory (DFT). The frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), natural bond orbitals (NBOs), global reactivity parameters (GRPs) and natural population (NPA) analyses were also carried out. The findings of FMOs found that Egap for HMBA was examined to be smaller (3.477 eV) than that of DHBA (3.7933 eV), which indicated a greater charge transference rate in HMBA. Further, the NBO analysis showed the efficient intramolecular charge transfer (ICT), as studied by Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

A Green, efficient and clean route for synthesis of biologically potent pyrano[2,3-c]pyrazole derivatives has been developed in excellent yield, by using biodegradable ionic liquid 1-ethyl 3-methyl imidazolium acetate [(EMIM)Ac)] as a green catalyst via one-pot four-component condensation reaction of ethyl-acetoacetate, hydrazine-hydrate, malononitrile and carbonyl compounds at reflux condition in ethanol. The striking features of the protocol are a cleaner reaction profile, mild experimental procedure, applicable to extensive range of substrates and short reaction time. [ABSTRACT FROM AUTHOR]

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chromium is an important industrial raw material. As far as China is concerned, chromium is in great demand, which is dependent on imports and large emissions. So recovery of chromium has important economic and environmental protection value. The extraction and back extraction of Cr(III) from solution by the extractant diisooctyl phosphate (di‐2‐ethylhexylphosphoric acid [D2EHPA]) with n‐octanol as assistant and sulphonated kerosene as diluent was studied. The effects of saponification rate, phase ratio, temperature, condensation of extract, aging of extractant, and pH of aqueous phase on extraction equilibrium were discussed, and the formulation of extractant was optimized. The coordination number of the extraction reaction under specific conditions was discussed by the saturation capacity method. The extraction reaction kinetics were mathematically characterized by binary linear regression. The advantages and disadvantages of back extraction with H2SO4 or NaOH were compared. At last, a process to realize the recycling of extractant was obtained. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 3‐methyl‐4‐(arylmethylene)isoxazol‐5(4H)‐ones are developed via cyclocondensation in 84–94 % yields starting from aromatic aldehydes, hydroxylamine with ethyl acetoacetate vitamin B1 is catalyzed under ultrasound radiation, and are characterized by HR‐MS, FT‐IR and 1H and 13C NMR spectroscopy. The reaction has simple operation, metal‐free catalysis, acid or base free catalysis. As a green catalyst, vitamin B1 is found to possess favorable catalytic activity and reusability for the condensation reaction. 5‐(2‐Hydroxy‐3‐methoxybenzylidene)‐3‐methylisoxazol‐5(4H)‐one as a metal ion fluorescent probe, has excellent selectivity to Sr2+ and exhibits obvious discoloration. Fe2+ quenches the fluorescence of the ligand 3‐methyl‐4‐(2,3,4‐trihydroxybenzylidene)isoxazol‐5(4H)‐one, and exhibits an obvious color change. [ABSTRACT FROM AUTHOR]

A heteroleptic binuclear manganese complex was obtained and characterized by single-crystal X-ray diffraction. Manganese ions coordinate with the target product and by-product of the condensation reaction between 2-picolylamine and acenaphthenequinone are characterized by different geometries in the resulting complex. [ABSTRACT FROM AUTHOR]

Ester compounds, widely found in pharmaceutical and natural products, play a crucial role in organic synthesis, prompting the development of numerous methods for their synthesis. An important chemical approach in synthesizing esters from carboxylic acids involves the activation of the carboxyl function, requiring the conversion of the hydroxyl group into a suitable leaving group. This paper presents the findings of our investigations into an efficient method for producing esters from carboxylic acids and alcohols, using the Lewis acid titanium tetrachloride. Titanium tetrachloride has proven highly effective as a coupling reagent for the one-pot formation of esters from carboxylic acids and alcohols operating under mild and neutral conditions. Notably, the reaction eliminates the need for bases, yielding carboxylic esters in high purity and yields. The method is efficient, even with long-chain carboxylic acids, and operates well with primary alcohols in dichloromethane. Steric hindrance, potentially present in carboxylic acids, has a moderate effect on the reaction. Alcohol substrates that easily form stable carbocations require, instead, the use of non-polar solvents like hexane for the reaction.

A heteroleptic binuclear manganese complex was obtained and characterized by single-crystal X-ray diffraction. Manganese ions coordinate with the target product and by-product of the condensation reaction between 2-picolylamine and acenaphthenequinone are characterized by different geometries in the resulting complex.

The condensation of 2-alkylsulfanyl-substituted 2-en-4-ynals with N,N- and N,O-binucleophiles gives the corresponding 1,3-perhydrodiazines, 1,3-imidazolidines, and 1,3-oxazolidines with the original combination of substituents. [ABSTRACT FROM AUTHOR]

A novel catalytic approach for the synthesis of symmetric and asymmetric azines has been developed. The environmentally benign protocol was achieved via condensation of 1-[(2-thienyl)ethylidene]hydrazine (1) with different aromatic aldehydes 2a–h and acetyl heterocyclic compounds (4, 6, 8, 10, and 12) in the presence of cellulose sulfuric acid (CSA) as the green catalyst. These procedures offer an interesting method for the large-scale industrial manufacture of azines due to their high percentage yield, mild reaction conditions, broad substrate range, and utilization of an economical and environmentally acceptable catalyst. Additionally, the molecular docking of the products to the monoamine oxidase (MAO-A) target protein was achieved to highlight the possible binding interaction with the amino acid residues Arg51, Glu43, Gly22, Gly49, Gly443, Ala272, Ile335, and Tyr407 at the point of binding. The binding interaction energy was discovered to be (− 6.48 kcal/mol) for the protein MAO-A (PDB ID: 2Z5X). The most effective azine derivatives 7 and 13 revealed some major conserved interactions between the MAO-A protein's binding site amino acid residues and the PDB co-crystal ligand 2Z5X. Moreover, azine derivatives 3a and 3f showed the lowest binding activity with the target MAO-A. [ABSTRACT FROM AUTHOR]

A facile synthetic strategy for the synthesis of a new series of β,β'‐fused 2‐arylpyrimido[4,5‐b]porphyrins has been developed by using condensation cyclization reaction with ammonia. 2‐Aroylamino‐3‐formylporphyrins were synthesized from 2‐aroylaminoporphyrins under Vilsmeier–Haack reaction conditions, which were then efficiently converted to the corresponding 2‐arylpyrimido[4,5‐b]‐5,10,15,20‐tetrakis(4‐chlorophenyl)‐porphyrins via a condensation cyclization reaction. The nickel(II), copper(II), free‐base and zinc(II) analogues of 2‐arylpyrimido[4,5‐b]porphyrins were successfully synthesized in 65–72 % yields and structurally characterized on the basis of spectral data analysis. On photophysical evaluation, 2‐arylpyrimido[4,5‐b]porphyrins demonstrated a 12–19 nm bathochromic shift in their electronic absorption spectra and up to 10 nm red shift in their emission spectra as compared to the simple meso‐(tetrakis(4‐chlorophenyl))porphyrins due to the extended π‐conjugation. [ABSTRACT FROM AUTHOR]

This paper is intended to prepare new antimicrobial complexes with proven efficiency. The Schiff base, through the condensation process of salicylaldehyde and p-toludine, and its Cu and Zn complexes were successfully synthesized. The Schiff base and its complexes were characterized using molar conductivity, Ultraviolet-visible (UV-Vis), atomic absorption spectroscopy (AAS), and Fourier transform infrared (FTIR) techniques. Accordingly, these characterizations not only confirmed that the synthesized Schiff base acted as N,O bidentate ligand (through azomethine nitrogen and phenoxide oxygen) and chelated with Cu(II) and Zn(II) in the metal-to-ligand ratio of 1:2 but also revealed the characteristic electronic-transition of π→π*/n→π* of the ligand, and ligand-metal charge transfer and d-d of the metal complexes. Moreover, both Cu and Zn complexes recorded weak molar conductance of 54.12 and 51.41 S cm² mol-1, respectively. Further, their antibacterial activities were evaluated by disc diffusion assay against Staphylococcus aureus (gram-positive), Escherichia coli (gram-negative), and Bacillus cereus (gram-negative) bacteria. For all microbial, the metal complexes recorded higher activities than the parent ligand; such increased activity of the complexes may be due to the chelation of the metal ion in the complexes, which enhances the lipophylic character favoring its permeation through the lipid layer of the cell membrane. Such metal complexes can therefore be explored in the future as an option for decreasing the pathogenic potential of infecting bacteria. [ABSTRACT FROM AUTHOR]

Coal fly ash was transformed into a bifunctional catalyst bearing strong Lewis–Bronsted acid sites to catalyze the condensation of 2-naphthol and aromatic aldehydes under microwave irradiation. Due to the high thermal stability of its component, fly ash was employed as support for the incorporation of sulfated tin oxide to enhance Lewis–Bronsted acid sites for organic reactions. Fly ash was first mechanically activated for 15 h to enhance its reactivity followed by loading of sulfated tin oxide as an active species in varying amounts (4.6–13.4 wt%) and analyzed by various surface characterization techniques. The Bronsted acid sites were developed from the surface hydroxyl groups associated with metal oxides that existed in the fly ash skeleton. In contrast, Lewis acid centers were generated due to the sulfated tin oxide bonded with the fly ash matrix. The prepared catalyst promoted the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes with a high yield of > 90%, which is attributed due to high crystallinity (> 70%) and evenly distributed Bronsted–Lewis acid sites. The catalyst was stable and successfully recycled five times without any significant leaching of Sn and other elements of fly ash. The present study is of great significance in utilization of fly ash for the development of heterogeneous catalyst with high stability, activity and low cost. [ABSTRACT FROM AUTHOR]

A number of nitrones have been synthesized in three different procedures, starting with N-phenyl hydroxylamine, followed by the condensation reaction with some selected aldehydes. Furthermore, these nitrones were employed in the preparation of a number of new isoxazolidines. Cycloaddition reaction of nitrones to styrene produced the desired products. [ABSTRACT FROM AUTHOR]

A one-pot, sequential, three-component procedure is reported for the synthesis of poly-substituted dihydropyridines via the condensation reaction of diamines or aminophenoles, 1,1-bismethylmethio-2-nitroethylene and α , β -unsaturated aromatic ketones in acetonitrile under reflux conditions. A range of fused and non-fused poly-substituted dihydropyridines were prepared in good to high yields with short reaction times. [Display omitted] • Synthesis of 16 new derivatives with potential biological activity from the family poly-substituted dihydropyridine. • Development a new synthetic method in the absence of any base and catalyst. • Taking advantage of multicomponent reactions for the synthesis of new compounds. • Operational simplicity with no column chromatography to purify products. [ABSTRACT FROM AUTHOR]