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The rapid development in bacterial resistance to many groups of known antibiotics forces the researchers to discover antibacterial drug candidates with previously unknown mechanisms of action, one of the most relevant being the inhibition of tRNA (Guanine37-N1)-methyltransferase (TrmD). The discovery of selective TrmD inhibitors in the series of carboxamide derivatives of thienopyrimidines became a background for further modification of the similar structures aimed at the development of promising antibacterial agents. As part of this research, we carried out the construction of heterocyclic hybrids bearing the moieties of thieno[2,3-d]pyrimidine and benzimidazole starting from 3,5-dimethyl-4-oxo-2-thioxo-1H-thieno[2,3-d]pyrimidine-6-carboxylic acid, which was used as the pivotal intermediate. The hybrid molecule of 6-(1H-benzimidazol-2-yl)-3,5-dimethyl-2-thioxo-1H-thieno[2,3-d]pyrimidin-4-one prepared via condensation of the carboxylic acid with ortho-phenylenediamine was further alkylated with aryl/hetaryl chloroacetamides and benzyl chloride to produce the series of S-alkyl derivatives. The results of molecular docking studies for the obtained series of S-alkyl benzimidazole-thienopyrimidines showed their high affinity to the TrmD isolated from the P. aeruginosa. The results of antimicrobial activity screening revealed the antimicrobial properties for all of the studied molecules against both Gram-positive and Gram-negative bacteria and the Candida albicans fungal strain. The highest antimicrobial activity was determined for 2-{[6-(1H-benzimidazol-2-yl)-3,5-dimethyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidin-2-yl]thio}-N-(4-isopropylphenyl)acetamide, which also had the highest affinity to the TrmD inhibitor’s binding site according to the docking studies results. [ABSTRACT FROM AUTHOR]

In the present work, vinyl benzyl chloride (VBC) was polymerized by using free radical polymerization. The obtained PVBC was reacted with dibutyl amine to obtain tertiary amine modified polystyrene based polymer (PVBC-Dibutyl amine). The inverse gas chromatography (IGC) method was used to examine the thermodynamic properties of the polymer. Firstly, the retention diagrams of some polar and non-polar solvents on PVBC-Dibutyl amine were obtained over a temperature range from 135 to 160° C. Then, the thermodynamic parameters, including Flory-Huggins interaction parameter, weight fraction activity coefficient, partial molar heat of sorption, and partial molar heat of mixing were determined via interactions between the polymer and selected solvents at infinite dilution. The results reveal that the alkanes are poor solvents for the polymer whereas n-butyl acetate, i-butyl acetate, ethyl acetate, n-propylbenzene, i-propylbenzene, and ethylbenzene are moderately solvents in the studied temperature range. [ABSTRACT FROM AUTHOR]

Extreme conditions and the availability of determinate substrates in oil fields promote the growth of a specific microbiome. Sulfate-reducing bacteria (SRB) and acid-producing bacteria (APB) are usually found in these places and can harm important processes due to increases in corrosion rates, biofouling and reservoir biosouring. Biocides such as glutaraldehyde, dibromo-nitrilopropionamide (DBNPA), tetrakis (hydroxymethyl) phosphonium sulfate (THPS) and alkyl dimethyl benzyl ammonium chloride (ADBAC) are commonly used in oil fields to mitigate uncontrolled microbial growth. The aim of this work was to evaluate the differences among microbiome compositions and their resistance to standard biocides in four different Brazilian produced water samples, two from a Southeast Brazil offshore oil field and two from different Northeast Brazil onshore oil fields. Microbiome evaluations were carried out through 16S rRNA amplicon sequencing. To evaluate the biocidal resistance, the Minimum Inhibitory Concentration (MIC) of the standard biocides were analyzed using enriched consortia of SRB and APB from the produced water samples. The data showed important differences in terms of taxonomy but similar functional characterization, indicating the high diversity of the microbiomes. The APB and SRB consortia demonstrated varying resistance levels against the biocides. These results will help to customize biocidal treatments in oil fields. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She 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.)

[Display omitted] • Environmentally friendly D-Mt composite is prepared. • The adsorption of AMP and AMX by D-Mt-1.4 under different conditions was studied. • DFT was applied to quantitatively analyze the molecular surface of AMP and AMX. • Multiwfn program was applied to quantitatively analyze the molecule surface. The quaternary ammonium surfactant-dodecyl benzyl ammonium chloride (DDBAC) was applied to modify Ca-montmorillonite (Ca-Mt) to obtain organo D-Mt that was used as the adsorbent for micropollutants-ampicillin (AMP) and amoxicillin (AMX). The XRD characterization indicated that DDBAC intercalated the interlayer space of Ca-Mt. When the amount of modifier was 1.4 CEC, the basal spacing enlarged from 1.53 nm to 2.97 nm, and the arrangement of modifier molecules were sloped in the interlayer of Ca-Mt along the longest axis. The saturated adsorption capacity of D-Mt-1.4 for AMP and AMX was 30.86 mg/g and 13.29 mg/g, respectively, while the saturated adsorption capacity of Ca-Mt for two contaminants was only 0.36 mg/g and 0.16 mg/g, respectively. The adsorption of the two pollutants was more consistent with Freundlich adsorption isotherm second-order kinetic model, and the thermodynamic study suggested that adsorption was more likely to occur at higher temperatures, which means that the adsorption of two pollutants was a spontaneous endothermic process. Moreover, Multiwfn wavefunction program based on Density Functional Theory (DFT) was applied to reveal the microadsorption mechanism of D-Mt to two pollutant molecules. This work confirmed that Ca-Mt functionalized by DDBAC was promising adsorbents for micro-contaminants of antibiotics and the insight of the adsorption mechanism from the atomic level, providing theoretical guidance for architecting high performance adsorbent. [ABSTRACT FROM AUTHOR]

A novel sulfated-group-riched sulfonated carbonaceous catalyst with high acidic strength and adjustable ratio of acidic groups was designed in the paper, where glucose and benzyl chloride were hydrothermally carbonized first followed by sulfonation treatment. Various physicochemical techniques were used to characterize the catalyst such as IR, 13C MAS NMR and XPS spectra, NH3-TPD, XRD patterns and TG curve. Then, it was applied in the esterification of succinic acid and fructose dehydration to form HMF. Compared to commercial Amberlyst-15 catalyst, such carbonaceous solid acid exhibited excellent catalytic activity and thermal stability, which was attributed to its higher amount of sulfonic acid group. [ABSTRACT FROM AUTHOR]

• The variation Characteristics of ambient VOCs on haze days and non-haze days were discussed in Zhengzhou. • Five sources of VOCs were identified by the PMF model. • Vehicle exhaust and industrial production were the largest sources of VOCs in winter. • Healthy risk of VOCs during different pollution episodes were estimated. Zhengzhou is one of the most haze-polluted cities in Central China with high organic carbon emission, which accounts for 15%-20% of particulate matter (PM 2.5) in winter and causes significantly adverse health effects. Volatile organic compounds (VOCs) are the precursors of secondary PM 2.5 and O 3 formation. An investigation of characteristics, sources and health risks assessment of VOCs was carried out at the urban area of Zhengzhou from 1st to 31st December, 2019. The mean concentrations of total detected VOCs were 48.8 ± 23.0 ppbv. Alkanes (22.0 ± 10.4 ppbv), halocarbons (8.1 ± 3.9 ppbv) and aromatics (6.5 ± 3.9 ppbv) were the predominant VOC species, followed by alkenes (5.1 ± 3.3 ppbv), oxygenated VOCs (3.6 ± 1.8 ppbv), alkyne (3.5 ± 1.9, ppbv) and sulfide (0.5 ± 0.9 ppbv). The Positive Matrix Factorization model was used to identify and apportion VOCs sources. Five major sources of VOCs were identified as vehicular exhaust, industrial processes, combustion, fuel evaporation, and solvent use. The carcinogenic and non-carcinogenic risk values of species were calculated. The carcinogenic and non-carcinogenic risks of almost all air toxics increased during haze days. The total non-carcinogenic risks exceeded the acceptable ranges. Most VOC species posed no non-carcinogenic risk during three haze events. The carcinogenic risks of chloroform, 1,2-dichloroethane, 1,2-dibromoethane, benzyl chloride, hexachloro-1,3-butadiene, benzene and naphthalene were above the acceptable level (1.0 × 10−6) but below the tolerable risk level (1.0 × 10−4). Industrial emission was the major contributor to non-carcinogenic, and solvent use was the major contributor to carcinogenic risks. [Display omitted] [ABSTRACT FROM AUTHOR]

Vehicular emissions have become a primary anthropogenic source of urban atmospheric volatile halogenated hydrocarbons (VHCs) with the rapid increase of vehicle population, while characteristics of the VHC emissions from different vehicles were rarely systematically investigated. In this study, the on-road tailpipe emissions were sampled from seven in-use vehicles, including two light-duty gasoline vehicles (LDGV), three light-duty diesel trucks (LDDT), one heavy-duty diesel truck (HDDT), and a liquefied petroleum gas-electric hybrid bus (LPGB), using a portable emission measurement system (PEMS) combined with summa canisters, and 35 individual VHC species were identified by a gas chromatography mass spectrometry detector (GC-MSD). Results showed that VHC emissions under urban driving conditions were much higher than those on the suburban roads and highways. The VHC emission factors of LDGV were 1.2 ± 0.34 mg/km and 3.6 ± 1.5, 6.8 ± 0.89, and 1.6 ± 0.28 mg/km for LDDT, HDDT, and LPGB, respectively. For the LDGV, chlorobenzene, 1,2-dichloroethane, and hexachlorobutadiene were the top three VHC species. 1,2-Dichloroethane, trichloromethane, and methyl chloride were the main VHC constituents in the LDDT. Chlorobenzene was the most abundant VOC species for the HDDT, followed by 1,2-dichloroethane and 1,4-dichlorobenzene. The major species for LPGB were 1,2,4-trichlorobenzene, carbon tetrachloride, and benzyl chloride. The major tailpipe VHC species obtained in this study were partial consistent with previous studies with different test methods. The results provide an initial evaluation of the tailpipe VHC emissions, which may provide experimental data support for the refined source apportionment of atmospheric VHCs and the control of vehicular VHCs. [ABSTRACT FROM AUTHOR]

A photoredox/nickel dual catalyzed reductive hydrobenzylation of alkynes and benzyl chlorides by employing alkyl amines as a stoichiometric reductant is described. This synergistic protocol proceeds via Markovnikov-selective migratory insertion of an alkyne into nickel hydride, followed by cross-coupling with benzyl chloride, providing facile access to important 1,1-disubstituted olefins. This reaction enables the generation of nickel hydride by utilizing readily available alkyl amines as the hydrogen source. The mild conditions are compatible with a wide range of aryl and alkyl alkynes as well as chlorides. [ABSTRACT FROM AUTHOR]

1,2,4‐Triazole‐3‐one (3), acquired from cinnamaldehyde was converted to the corresponding carbox(thio)amides via several steps (6 a–c). Their reaction with sodium hydroxide gave the 1,2,4‐triazole derivatives (7 a–c). Compound 3 treatment with 2‐bromo‐1‐(4‐chlorophenyl) ethanone or 2‐chloro‐1‐(2,4‐dichlorophenyl)ethanone afforded the compounds 8 a,b and by reducing these compounds reduction products were obtained (9 a,b). The synthesis of (10 a–e) was carried out by the reaction compounds 9 a,b with different benzyl chlorides. Then oxadiazole derivative (12) was obtained by ring closure from hydrazide compound 5. Subsequently compounds 3, 7 a–c, and 12 were treated with various amines in the presence of formaldehyde to yield Mannich bases (11 a–e, 14 a–e, 13 a,b). Microwave‐assisted and conventional techniques were utilized for the syntheses. The structures of newly synthesized compounds were illuminated by spectroscopic methods. Their antimicrobial (MIC method), and anticancer activities (Abay's method) were examined. Results showed that most of the compounds exhibited good antimicrobial activities. Especially compounds 14 a–e which is a mannich base showed very good antitubercular activity against Mycobacterium smegmatis compared with Streptomycin standard drug. Also compounds 8 a and 9 b have been found to have strong antiproliferative effects on the HeLa cervical cancer cells and also these compounds did not have a cytotoxic effects on a normal cells. [ABSTRACT FROM AUTHOR]

An efficient and metal‐free methodology for the oxidation of benzyl halides to benzoic acids using an inexpensive and green oxidant (TBHP) in aqueous basic medium has been developed. This protocol offers an excellent way to avoid adding catalysts and involves the use of an in‐situ generated halide ion as catalyst. It is also the first report on the oxidation of benzyl iodides to benzoic acids. A series of carboxylic acids were prepared from benzyl halides in high yields under mild reaction conditions by this method which does not require chromatographic purification. Gram scale reactions for the synthesis of the carboxylic acids in good yields have been successfully carried out using benzyl chloride, bromide and iodide. As an industrial application, the synthesis of a key monomer used for the synthesis of polyethylene terephthalate (PET), i. e. terephthalic acid (PTA), has also been accomplished in good yields. [ABSTRACT FROM AUTHOR]

It is desirable for a simple and universal method to synthesize stimuli‐responsive nanocarriers to targeted delivery of pesticides. In this study, a novel pH‐value and laccase dual‐responsive nanopesticide system loaded with lambda‐cyhalothrin (LC) is established by iron mineralization after electrostatic self‐assembly between sodium lignosulphonate (SL) and dodecyl dimethyl benzyl ammonium chloride (DDBAC). These nanoparticles are core–shell structures in which iron mineralization plays a key role in stabilizing the nanoparticles. This synthesis strategy is suitable for encapsulating hydrophobic and low‐volatility compounds. The encapsulation of the nanocarriers prolongs the half‐life of the LC under UV irradiation by 4.4‐fold. After irradiation, the mortality of Agrotis ipsilon treated by the LC@SL/DDBAC/Fe is approximately 39% higher than that treated by emulsifiable concentrate (EC) at the concentration of 1 mg L−1. The dual‐responsive property of lignin‐based nanoplatform to alkalinity and laccase enable cargo release on demand. Although the toxicity of EC and LC@SL/DDBAC/Fe to A. ipsilon is similar, that of LC@SL/DDBAC/Fe to Brachydanio rerio is decreased by 11.57‐fold, and the toxicity selective pressure is enhanced by 11‐fold compared with EC. The SL/DDBAC/Fe nanocarriers represent a simple preparation procedure, excellent environmental safety, and dual‐responsive release profiles and can offer a promising nanoplatform for precise pesticide delivery. [ABSTRACT FROM AUTHOR]

This work reports an extension of Menshutkin reaction and involves the studies on kinetics of quaternization reaction between N,N-Dimethylaniline and benzyl chloride in acetone and in other various solvents at 300 K. The progress of the reaction was followed by measuring the conductance of the product formed at regular intervals of time. The effect of [benzyl chloride] and [N,N-Dimethylaniline] on reaction rate was studied under pseudo-first order condition and the rate showed first order dependence on both [benzyl chloride] and [N,N-Dimethylaniline]. The effect of dielectric constant of the medium on reaction rate was studied by employing various solvents such as methyl ethyl ketone, isopropyl alcohol, ethyl alcohol, methyl alcohol and acetonitrile and the rate is found to increase with increase in dielectric constant of the medium. The linear plot with a negative slope on plotting log k2 against 1/D where D is the dielectric constant of the medium indicates the existence of a highly charged or a polar transition state during the progress of the reaction. The quaternization reaction was also carried out at different temperatures so as to compute the various thermodynamic parameters like activation energy, enthalpy of activation, entropy of activation and Gibb’s free energy change. The higher value of activation energy is attributed for a slower reaction which is sterically controlled rather than thermodynamically controlled. The negative value of entropy of activation (∆S*) indicates some sort of surrendering of disorder in the transition state on its formation which proves that it is highly ordered with sufficient charge separation and polar in character. The product after purification was analysed by melting point and infra-red spectral analysis and is proved to be N-Benzyl-N,N-dimethylphenylmethanaminium chloride. A plausible mechanism in accordance with the obtained experimental results is reported. [ABSTRACT FROM AUTHOR]

VUV/UV photodegradation technology, which is free of catalysts or oxidants, has been regarded as an efficient method to decompose gaseous VOCs. However, the mineralization of gaseous VOCs by VUV/UV photodegradation has seldom been discussed systematically. In this work, the mineralization of benzyl chloride in humid air is comprehensively investigated and the potential contributors in the system (i.e., light wavelength, O2 and H2O) are discussed. As a result, more than 95.0% benzyl chloride is mineralized at 40 min in humid air with 80% relative humidity (RH) despite its initial concentrations (i.e., ranging from 4 to 20 ppm). It is found that both 185-nm VUV light and H2O significant contribute to the efficient mineralization of benzyl chloride in humid air, while O2 only has a limited effect to the efficient mineralization of benzyl chloride in humid air. The introduction of H2O into the VUV/UV photodegradation can reduce the emission of ozone obviously. These findings are significant inspiration to application of the VUV/UV photodegradation technology on the treatment of gaseous VOCs in the actual air atmosphere. [ABSTRACT FROM AUTHOR]

Reaction of thiols with α‐(trifluoromethyl)styrenes under photocatalytic conditions leading to desulfurative allylic fluorine substitution is described. The reaction is performed by treatment of thiols with benzyl zinc chloride to generate zinc thiolates followed by visible light induced desulfurization by means of triphenylphosphine. Radicals formed after the C−S bond cleavage react with the double bond affording gem‐difluorostyrenes. [ABSTRACT FROM AUTHOR]

In this work, poly(glycidyl methacrylate) (PGMA, G) homopolymers with different molecular weights (5600–21,000 gmol−1) were synthesized by atom transfer radical polymerization (ATRP) method. Epoxy groups of PGMA homopolymers were converted to hydroxyl and 1‐methyl piperazin residues by reacting with 1‐methyl piperazine via ring‐opening reaction. The obtained poly(2‐hydroxy‐3‐methyl piperazinepropyl methacrylate) (PHMPPMA, G‐P) homopolymers (from 9450 to 35,900 gmol−1) were reacted with alkyl halides of different carbon chain lengths (methyl‐, ethyl‐, propyl‐, butyl‐, pentyl‐iodides, hexyl bromide) and benzyl chloride (arylhalide) to form quaternary PHMPPMA homopolymers (G‐QP). MIC values varied from 0.125 mg/ml to 5 mg/ml. It was found that homopolymer (1G‐6QP) produced by the modification of PHMPPMA with hexyl iodide with low molecular weight had highest quorum‐sensing inhibition zone ranging from 14.5 ± 0.5 mm (MIC) and 10.0 ± 0.5 mm (MIC/4) as well as best violacein inhibition 61.0 ± 2.2% (MIC) to 17.3 ± 0.6% (MIC/8). Homopolymer (1G‐BzQP) produced by the modification of PHMPPMA with benzyl chloride with the lowest molecular weight had best biofilm inhibition ranging from 77.83 ± 1.60% (MIC) to 18.23 ± 0.87% (MIC/8) on S. aureus, 75.70 ± 5.20% (MIC) to 14.25 ± 1.10% (MIC/8) on E. coli and from 86.16 ± 0.83% (MIC) to 12.41 ± 0.76% (MIC/8) on C. albicans. The synthesized homopolymers can be used to combat microbial resistance and severity of infections. [ABSTRACT FROM AUTHOR]

The Pd complex immobilized on the functionalized polymeric support was prepared by the functionalization of the 4‐(benzyloxy)benzyl chloride polymer with 5‐phenyl‐1‐H‐tetrazole and the subsequent complexation with PdCl2. Then, it was characterized with different methods and used as catalyst in the green benzylation reaction of various aryl cyanamides with benzyl bromide and K2CO3 in EtOH at 60°C for the appropriate times. Also, the antibacterial properties of the Pd polymer‐supported complex were studied against a number of gram‐positive and gram‐negative bacteria, and in some cases, it has the same effect as a tetracycline standard antibiotic against Bacillus thuringiensis (a gram‐positive bacterium) and Serratia marcescens (a gram‐negative bacterium). [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics 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.)

Non‐leaching antibacterial coatings through quaternary ammonium salts containing polymers were successfully produced in a facile way to provide infection resistant surfaces against multi drug resistant bacteria such as B. licheniformis. In order to do so, a series of random copolymers of styrene (S) and vinyl benzyl chloride (VBC) were synthesized by free radical polymerization technique and subsequently, VBC (V) was functionalized with N,N‐dimethylhexadecylamine to introduce quaternary ammonium (QA) salts in the backbone of the copolymers. The copolymers showed an excellent film forming ability, thereby providing an ultrathin coating on various substrates such as metal (stainless steel), glass, polyethylene and polystyrene, as observed by SEM.The coatings were found to be uniform, non leachable in aqueous medium and exhibit good adhesion to various substrates. The antibacterial and antibiofilm activity of the non‐leachable coating of random copolymers were screened against B. licheniformis. Among, the copolymer containing 75% quaternized VBC (75VSQA) having 16‐C long alkyl chain was found to show maximum antibacterial and antibiofilm activity owing to an appropriate hydrophobic /hydrophilic balance. Their non‐leachable antibacterial and antibiofim activity make these coatings suitable for many applications, e.g. marine paints, textile/hospital coatings etc. [ABSTRACT FROM AUTHOR]

A convenient procedure for the synthesis of thioesters has been developed via a palladium‐catalyzed thiocarbonylation of benzyl chlorides with sulfonyl chlorides. Various arylacetyl thioesters were produced in good yields by using sulfonyl chlorides as an odorless sulfur source. Furthermore, W(CO)6 exhibited dual roles as both a solid CO surrogate and reductant here. [ABSTRACT FROM AUTHOR]

The increasing resistance of antibiotics and the global spread of pathogenic bacteria highlight the urgent need for novel antibacterial materials. In this study, a terpolymer (PVBA) with carboxyl (-COOH) and benzyl chloride (-C 7 H 6 Cl) groups was synthesized using acrylic acid (AA), butyl acrylate (BA), and 4-vinyl benzyl chloride (VBC) as monomers. The -C 7 H 6 Cl groups in the PVBA terpolymer was then reacted with N-N-dimethylhexadecane 1-amine (HAM) to prepare a more hydrophilic antibacterial (PVBA-N) terpolymer. Further, a synthetic/natural (PVBA-N/C) composite with quaternary ammonium (QA) groups was prepared by covalent crosslinking of the PVBA-N terpolymer and chitosan (CS). Finally, the AgCl-decorated PVBA-N/C (AgCl@PVBA-N/C) antibacterial composite was were constructed by anchoring silver chloride nanoparticles (AgClNPs) to the surface of the PVBA-N/C composite. Remarkably, the resulting AgCl@PVBA-N/C antibacterial composite had a porous network structure and exhibited favorable antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) based on both contact-typed and release-typed antibacterial modes, and low cytotoxicity against L929 cells. This research provides an effective strategy to combat the threat of bacterial resistance to human health relying on the advantage of the respective antibacterial mechanisms of various antibacterial ingredients. [Display omitted] • An organic/inorganic antibacterial (AgCl@PVBA-N/C) composite was prepared by a dual modification strategy. • The AgCl@PVBA-N/C composite combated bacteria via both contact-type and release-type mechanisms. • The AgCl@PVBA-N/C composite possessed good antibacterial activity and low cytotoxicity. • The AgCl@PVBA-N/C composite has a bright prospect against the threat of bacterial resistance. [ABSTRACT FROM AUTHOR]

This work provides a more favorable implementation of synergistic drag reduction strategies based on molecular simulations of the strength of polymer-surfactant interactions. The simulated preferred system identifies polyethylene oxide (PEO) and guar gum (GG) as polymers, and dodecyl dimethyl benzyl ammonium chloride (DDBAC) and dodecyl hydroxy sulfobetaine (DHSB). To forecast the drag reduction capability and identify the drag reduction process, important elements such as aggregation phenomena, charge distribution, shear deformation, and interfacial behavior were examined. Experimental measurements of viscosity, surface tension, and drag reduction validate the interactions. It was found that the compound system demonstrates enhanced viscosity, surface tension, and drag reduction efficiency compared to individual systems. The PEO-DHSB system achieves a drag reduction rate of 63.68% during initial flow, while the GG-DHSB system maintains a rate of 47.26% even after prolonged water circulation. This work visualizes the poly-surface aggregation phenomenon using the density distribution of surfactant hydrophobic tail chains, dynamically demonstrating the deformation of polymer and surfactant molecules during the shear process and interfacial behavior, and providing molecular-scale intuitive insights for understanding the drag reduction mechanism of poly-surface systems. Meanwhile, by comparing the effects of molecular type and structure on poly-surface interactions and drag reduction performance, it provides a theoretical foundation for the development and application of subsequent poly-surface drag reduction schemes, thereby broadening the application of drag reduction technology in the field of energy conservation and emission reduction. [Display omitted] [ABSTRACT FROM AUTHOR]

A phenolic hydroxyl-functionalized imidazolium ionic polymer (IP 1) with lower activation energy was designed and synthesized successfully via a one-pot quaternization, which exhibits excellent catalytic activities for CO 2 fixation under mild conditions. [Display omitted] • Phenolic imidazolium ionic polymers (IPs) are prepared via a one-pot method. • Excellent catalytic activities of IPs on CO 2 conversion are achieved. • IP 1 presents good recyclability and substrate universality. • IP 1 features low activation energy with the first-order reaction kinetics. • Synergistic catalytic mechanism involving H-bond and halogen anion is proposed. Developing a greener and efficient catalysts towards the direct fixation of atmospheric CO 2 and then being used to synthesize high-value chemicals is of great interest, but challenging. To achieve this aim, rational design of the catalyst is very important. Herein, three imidazolium-based ionic polymers (IPs), named as IP 1–IP 3 , are straightforwardly synthesized through a simple one-pot quaternization method by employing benzyl chloride linkers and tri-imidazole monomers (L 1 and L 2). These IPs are fully characterized using FTIR spectroscopy, 13C MAS NMR, XRD, elemental analysis, SEM with elemental mapping, HRTEM, TGA, XPS spectroscopy, nitrogen adsorption–desorption, and CO 2 /NH 3 -TPD methods. The newly synthesized IP 1 catalyst with phenolic hydroxyl shows an excellent catalytic activity toward CO 2 cycloaddition with 97.1 % yield of cyclic carbonate under mild conditions (80 °C, 0.1 MPa CO 2 , solvent-free, 4.5 h). Moreover, the IP 1 catalyst is highly robust and can be reused at least for 7 consecutive runs. Mechanistic studies indicate that the synergic effect of hydrogen bonding and halogen anion in the IP 1 catalyst afford the ability to activate the substrate and ease the reaction kinetics, which results in an enhanced catalytic efficiency toward CO 2 fixation. This work provides an efficient new method for the design and synthesis of multifunctional heterogeneous catalysts for the CO 2 cycloaddition reaction. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed double carbonylation of propargyl amines and benzyl chlorides employing benzene‐1,3,5‐triyl triformate (TFBen) as the CO source has been developed. By using this protocol, various 1,5‐dihydro‐2H‐pyrrol‐2‐ones were produced in good yields. [ABSTRACT FROM AUTHOR]

In the present study, poly(vinyl benzyl chloride) (PVBC) was prepared by the radical polymerization method. Then, PVBC was reacted with dibutyl amine to obtain tertiary amine-modified poly(styrene) based polymer (PVBC-Dibutyl amine) and the resulting polymer was characterized. Surface properties of the polymer were investigated by inverse gas chromatography method at infinite dilution region. For this purpose, the retention diagrams of carefully selected polar and non-polar solvents (probes) on PVBC-Dibutyl amine were obtained over a temperature range from 30 to 50 ∘ C . By using the diagrams, the dispersive component of the surface free energy of the polymer surface was calculated for the studied temperatures by two different methods. The specific enthalpy of adsorption and the specific component of the adsorption free energy of solvents on PVBC-Dibutyl amine which are adsorption thermodynamic parameters were determined for each solvent used. Using the adsorption data, Lewis acid and Lewis base parameters of PVBC-Dibutyl amine surface were calculated. The obtained parameters reflected that surface of PVBC-Dibutyl amine exhibited a basic behavior. Considering the values in the literature, the effect of dibutyl amine moieties in the structure of poly(styrene) based polymer PVBC-Dibutyl amine on the dispersive surface free energy and acid–base parameters of poly(styrene) was discussed. [ABSTRACT FROM AUTHOR]

Investigations concerning the reactivity of the N‐heterocyclic silylene Dipp2NHSi (1, 1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐en‐2‐ylidene) towards selected alanes and boranes, elemental halides X2 (X=Br, I), selected halide containing substrates such as tin chlorides and halocarbons, as well as organoazides are presented. The NHSi adducts Dipp2NHSi⋅AlI3 (2), Dipp2NHSi⋅Al(C6F5)3 (3), and Dipp2NHSi⋅B(C6F5)3 (4) were formed by the reaction of Dipp2NHSi with the corresponding Lewis acids AlI3, Al(C6F5)3 and B(C6F5)3. Adducts 3 and 4 were tested with respect to their ability to activate small organic molecules, but no frustrated Lewis pair reactivity was observed. Reactions of Dipp2NHSi with Br2, I2, Ph2SnCl2 and Me3SnCl led to formation of Dipp2NHSiBr2 (5), Dipp2NHSiI2 (6), Dipp2NHSiCl2 (7) and {(Me3Sn)N(Dipp)CH}2 (8), respectively. The reaction with the halocarbons methyl iodide, benzyl chloride, and benzyl bromide afforded the insertion products Dipp2NHSi(I)(CH3) (9), Dipp2NHSi(Cl)(CH2Ph) (10) and Dipp2NHSi(Br)(CH2Ph) (11). Reaction of Dipp2NHSi with the organoazides Ad‐N3 (Ad=adamantyl) and TMS‐N3 (TMS=trimethylsilyl) led to the formation of 1‐Dipp2NHSi‐2,5‐bis(adamantyl)‐tetrazoline (12) and bis(trimethylsilyl)amido azido silane (13), respectively. For 2,6‐(diphenyl)phenyl‐N3 C−H activation occurs and a cyclosilamine 14 was isolated. [ABSTRACT FROM AUTHOR]

Two novel types of anion exchange membranes (AEMs) having imidazolium-type functionalised nanofibrous substrates were prepared using the facile and potentially scalable method. The membranes' precursors were prepared by graft copolymerization of vinylbenzyl chloride (VBC) onto syndiotactic polypropylene (syn-PP) and polyamide-66 (PA-66) nanofibrous networks followed by crosslinking with 1,8-octanediamine, thermal treatment and subsequent functionalisation of imidazolium groups. The obtained membranes displayed an ion exchange capacity (IEC) close to 1.9 mmol g–1 and ionic (OH-) conductivity as high as 130 mS cm–1 at 80 °C. This was coupled with a reasonable alkaline stability representing more than 70% of their original conductivity under accelerated degradation test in 1 M KOH at 80 °C for 360 h. The effect of ionomer binder on the performance of the membrane electrode assembly (MEA) in AEM fuel cell was evaluated with the optimum membrane. The MEA showed a power density of as high as 440 mW cm−2 at a current density is 910 mA cm−2 with diamine crosslinked quaternized polysulfone (DAPSF) binder at 80 °C with 90% humidified H2 and O2 gases. Such performance was 2.3 folds higher than the corresponding MEA performance with quaternary ammonium polysulfone (QAPS) binder at the same operating conditions. Overall, the newly developed membrane was found to possess not only an excellent combination of physico-chemical properties and a reasonable stability but also to have a facile preparation procedure and cheap ingredients making it a promising candidate for application in AEM fuel cell. [ABSTRACT FROM AUTHOR]

A one-pot synthesis of new 3-benzylphthalide derivatives was developed by using a strategy based on tetrakis(dimethylamino)ethylene (TDAE). The reactions in the presence of TDAE of substituted benzyl chlorides with methyl 2-formylbenzoate or of substituted methyl-2-formylbenzoates with 4-nitrobenzyl chloride furnished the corresponding isobenzofuran-1(3 H)-one products in moderate to good yields. [ABSTRACT FROM AUTHOR]

Hierarchical ZSM‐5 zeolites were synthesized by in‐situ crystallization of mesoporous carbon‐silica composites with a well‐ordered SBA‐15 structure. The hierarchical ZSM‐5 zeolite possessed a rather high external surface area (205 m2/g) and pore volume (0.35 cm3/g) compared with the reference ZSM‐5 zeolite, as well as higher acid‐site accessibility to large molecules. In the naphthalene benzylation reaction, the hierarchical HZSM‐5 zeolite converted approximate 50 % of benzyl chloride in 100 minutes under mild conditions and showed a high stability, which could be ascribed to the improved diffusion ability and acid‐site accessibility. [ABSTRACT FROM AUTHOR]

The synthesis of C-ring quinoxaline-substituted sinomenine 1,2,3-triazole derivatives at the 4-OH via click reactions is accomplished, and a total of 16 novel sinomenine double N-heterocyclic derivatives are obtained in 74%–95% yields. The C-ring is first transformed into a 1,2-diketone structure under the action of hydrochloric acid, and then reacted with o -phenylenediamine to obtain a C-ring quinoxaline-substituted structure. The 4-OH of sinomenine reacts with chloropropyne to give an alkynyl sinomenine, and then reacts with sodium azide and various benzyl chlorides to give the target compounds. All the synthesized derivatives are characterized by Fourier-transform infrared spectrometry, high resolution mass spectrometry, 1H NMR, and 13C NMR spectroscopy. [ABSTRACT FROM AUTHOR]

In this study, an artificial stream mesocosm consisting of a head tank, faster-flowing riffle section, gravel section, pool section, lower-run section, and tail tank was installed to simulate a chemical spill in a river. The responses of freshwater periphyton algae, crustacea (Moina macrocopa), freshwater worm (Limnodrilus hoffmeisteri), benthic midge (Glyptotendipes tokunagai), and fish (Zacco platypus and Aphyocypris chinensis) were observed after exposure to benzyl chloride (classified as an accident preparedness substance, APS) at concentrations of 1, 2, and 4 µL/L for 22.5 h. Higher concentrations increased the inhibition (photosynthetic efficiency decrease) of periphyton algae and the mortality of M. macrocopa, whereas the reproduction of the female cladoceran decreased in the 4 µL/L treatment. Mortality of fish did not occur or was lower (≤20%) at all concentrations; however, toxic symptoms were observed for some time after chemical exposure termination and later, symptoms receded. G. tokunagai mortality increased at all concentrations except the control after seven days, and no significant toxic effects were observed in L. hoffmeisteri. The hazardous concentration of benzyl chloride was calculated as 94 µg/L. This study showed the different sensitivities of each species to benzyl chloride. The findings can assist in environmental risk assessment of APSs after chemical spills to protect Korean aquatic species.

Nano-α-Fe2O3 prepared using acid pickling waste as precursor was found to be an effective catalyst for benzylation aniline with benzyl chloride. However, the formation of a green solution was observed during the solvent-free benzylation. A yellow-green single crystal as a byproduct was recovered from the green reaction mixture and characterized by X-ray single crystal diffraction, 1H NMR, FT-IR and elemental analysis. The results showed that this single crystal was a composite structural complex constructed by [(C6H6–CH2)2NH–C6H6]FeCl4 and [(C6H6–CH2)2NH–C6H6]Cl in equimolar ratio. The formation of the complex led to the deactivation and non-reusability of α-Fe2O3 catalyst for catalyzing solvent-free N-benzylation of aniline with benzyl chloride. The forming mechanism of the crystal was also discussed. [ABSTRACT FROM AUTHOR]

Novel heteroleptic Ni (II) complexes bearing a highly hindered yet flexible IPr* ligand, Ni (IPr*)(PPh3)Br2 (1) and Ni (IPr*)(PCy3)Br2 (2) (IPr* = 1,3‐bis(2,6‐bis (diphenylmethyl)‐4‐methylphenyl)imidazol‐2‐ylidene), were easily prepared in 78% and 89% yield, respectively. Both were characterized by elemental analysis and NMR spectroscopy, and 1 was subjected to X‐ray crystallography. Compared with 2 and its analogue bearing a less sterically demanding IPr ligand (IPr = 1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene), complex 1 exhibited superior catalytic activity in the magnesium‐mediated reductive coupling of benzyl chlorides with aryl chlorides, featuring outstanding tolerance of both coupling partners with steric demand. This study discloses a ligand‐facilitated reductive coupling of benzyl chlorides with aryl chlorides, which provides a new and practical synthetic tool for the synthesis of diarylmethanes. [ABSTRACT FROM AUTHOR]

Zero-gap liquid alkaline water electrolyzers have great potential for hydrogen production. In order to enhance their actual performance, one of the key components to investigate is the anionic exchange membrane that allows the conduction of anions between the electrodes. This paper reports the preparation and characterization of membranes composed of a polybenzimidazole, either poly(2,5-benzimidazole) (ABPBI) or poly[2-2′-(m-phenylene)-5-5′-bibenzimidazole] (PBI), crosslinked with different ratios of poly(vinylbenzyl chloride) (PVBC), forming thermally stable and homogeneous films. Quaternization of these films with 1,4-diazabicyclo (2.2.2) octane (DABCO) followed by immersion in an alkaline solution lead to the introduction of quaternary ammonium groups and hydroxide anions respectively. Adequate thermal stability is observed in the temperature range of application (below 100 °C). Measurements of KOH and water and related swelling reflect the higher absorption capacity of ABPBI based membranes relative to PBI based ones. ABPBI-c-PVBC/OH 1:2 membranes at 50 °C are characterized by high ionic conductivity values (48 mS cm−1), reaching 380 mA cm−2 at cell voltage 1.98 V. In conclusion, we consider that these membranes are competitive candidates as anion exchange membranes for zero-gap alkaline water electrolyzers, and can be further enhanced to reach the performance of state of the art AEM's. Image 1 • Quaternized and crosslinked ABPBI-PVBC membranes are stable and homogeneous. • ABPBI-PVBC have higher density of QA sites, KOH uptake and conductivity than PBI-PVBC • Best performance is attained by the membranes with the highest PVBC content. • These membranes enable to operate alkaline electrolyzers under mild conditions. [ABSTRACT FROM AUTHOR]

A Novel series of thiazolidine-2, 4-dione compounds was synthesized under microwave irradiation and those compounds were evaluated for their biological property i.e. antimicrobial activity, against two Gram positive and two Gram negative bacterial strains additionally two fungal strains. Among the synthesized derivatives 9b, 9h and 9i were found to be the most effective antimicrobial compounds. All the prepared compounds were characterized for structural confirmation by IR, ¹HNMR, 13CNMR and Mass spectroscopy. [ABSTRACT FROM AUTHOR]

• A thalidomide derivative was assessed for its anti-inflammatory activity. • The derivative suppressed cytokine expression to a greater degree than thalidomide. • The derivative penetrated skin due to its feasible lipophilicity and small size. • This compound regulated inflammation via inhibition of MAPKs/NF-κB/AP-1 signaling. • Thalidomide analog has potential as a therapeutic agent against psoriasis. Thalidomide can be a TNF-α inhibitor for treating skin inflammation. This drug exhibits a strong toxicity that limits its application. We synthesized a thalidomide analog containing the benzyl chloride group (2-[1-(3-chlorobenzyl)-2,6-dioxopiperidin-3-yl]isoindoline-1,3-dione, CDI) to examine anti-inflammatory activity against psoriasis. The evaluation was conducted by the experimental platforms of in vitro TNF-α- or imiquimod (IMQ)-stimulated HaCaT cells and in vivo IMQ-induced psoriasiform plaque. Using the in vitro keratinocyte model, we demonstrated a greater inhibition of IL-1β, IL-6, and IL-24 by CDI than by thalidomide. No significant cytotoxicity was observed at 100 μM. CDI delivered facilely into the skin with a cutaneous targeting ability 228-fold greater than thalidomide. CDI caused a negligible irritation on healthy mouse skin. We showed that topically applied CDI reduced IMQ-induced red scaly lesions, hyperplasia, microabscesses, and cytokine expression in the mouse model. The skin-barrier function measured by transepidermal water loss (TEWL) could be partially recovered from 50.6–36.3 g/m2/h by CDI. The mechanistic study showed that CDI suppressed cytokine production by inhibiting the phosphorylation of NF-κB and AP-1 via MAPK pathways. CDI would be beneficial for the development of a therapeutic agent against psoriasis. [ABSTRACT FROM AUTHOR]

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Bis(β‐iminoenolate)copper(II) complexes with different substituents (3 a–c) have been prepared and explored the catalytic activity for azide‐alkyne cycloaddition reaction in environmentally benign condition. Copper complexes showed highly efficient catalytic activity and produced regioselective product of 1,4‐disubstituted‐1,2,3‐triazoles in one‐pot three component reaction between benzyl chloride, sodium azide and alkynes at room temperature in water medium. The structure‐activity comparison revealed that copper complex with electron withdrawing fluoro substituent (3 c) exhibited comparatively higher catalytic activity in azide‐alkyne cycloaddition reactions and produced up to 98 % of yield with 12.5 mol % of the catalyst without addition of any other reagent. [ABSTRACT FROM AUTHOR]

A series of catalysts was prepared for the liquid-phase Friedel–Crafts benzylation of toluene with benzyl chloride (BC) by impregnating rice husk ash silica with ZnCl2 (3 wt%, 6 wt%, 9 wt%, and 12 wt%) via a wet impregnation method. The XRD analysis indicates that the catalysts were amorphous with ill-defined pore systems. The XPS analysis detected the coexistence of ZnO nanoparticles together with ZnCl2 on the catalyst surface, whereas the 29Si NMR analysis indicates the formation of Si–O–Zn bond. Quantitative conversion of benzyl chloride (100%) was achieved within 3 h at 353 K when a catalyst with 9 wt% ZnCl2 was used due to its narrow pore size and high surface area (635 m2 g−1). Para- and ortho-mono-benzylated toluene was obtained as the products. The reaction is proposed to take place via weak attraction between benzyl chloride and the Zn through its chlorine atom. The catalyst was recycled four times with minimum loss (8%) in activity. The benzylation of benzene, toluene, p-xylene, and anisole followed the classical mechanism of Friedel–Craft-type acid-catalyzed benzylation reaction. The BC conversion increased in the order of toluene = p-xylene > anisole > benzene. The catalyst was also screened to be active in the benzoylation of toluene with benzoyl chloride (BOC). The conversion of BOC was 45% with selectivity toward 2-methylbenzophenone (50%) and 3-methylbenzophenone (50%). [ABSTRACT FROM AUTHOR]

A new series of 2-Mercaptobenzimidazole derivatives were synthesized. Quinazoline-4-one, thiazine-4-one and Tetrazoline derivatives. These compounds can be prepared by alkylation of 2-Mercaptobenzimidazole [2-MBI] with benzyl chloride in basic medium to produce 2- benzyl thiobenzimidazole [1], then the compound [1] was mixed with sodium hydride in dioxane at (0-5C0) to give the salt of compound [1]. Then the salt was reacted with ethyl chloro acetate to yield ethyl 2-(benzylthio) benzimidazole acetate compound [2] as a starting compound [2]. Thereafter, compound [2] was treated with hydrazine hydrate to afford N-acetohydrazide-2-(benzyl thio) benzimidazole [3] then reacted with a different substitution aromatic aldehyde in absolute ethanol to give Schiff's bases derivatives [4-10]. The reactions of compounds [4-10] were carried out through three pathways for cyclization: the first pathway involved a reaction with 2- amino benzoic acid to afford Quinazoline-4-one derivatives [11-17]. The second pathway consists of reaction with 2-marcaptobenzoic acid to produce thiazine-4- one derivatives [18-24]. The third pathway involved reaction with sodium azide to obtain tetrazoline derivatives [25-31]. The new prepared compounds were identified by [FTIR, 1H-NMR and 13C-NMR] and their physical properties were measured. Furthermore, we have evaluated of anti-oxidant activities in-vitro of the new synthesized compounds were tested with DPPH radical cation decolorization assays. [ABSTRACT FROM AUTHOR]

We utilized two-dimensional (2D) monolayer bismuthene nanosheet (BiNS) as the sensing material for detecting the hazardous vapor molecules benzyl chloride (BC) and chlorobenzene (CB) based on the DFT analysis. The target molecules BC and CB that are found in various industrial and commercial products are unfriendly compounds to humans that can cause damages such as nausea to the central nervous system. The bulk material bismuth exhibits metallic characteristics, which transforms to semimetal or semiconductor upon exfoliation to monolayer Bi. Hence, we used 2D layered Bi as a chemical sensor that works as chemiresistor for sensing BC and CB vapors. The research focuses on scrutinizing the transfer of charge (Q), band gap, and adsorption energies for interpreting various responses of vapor molecules upon adsorption on Bi using generalized gradient approximation/Perdew–Burke–Ernzerhof exchange correlation functional along with double-ζ-polarization basis set. The adsorption of BC and CB leads to a change in the projected density of state spectrum of BiNS. The current research aims towards the adsorption studies for sensing the unsafe BC and CB vapors using BiNSs. [ABSTRACT FROM AUTHOR]

While the popularity of electronic cigarettes (e-cigarettes) has rapidly increased in recent years, the regulation around the composition of such e-cigarettes has lagged. Many components of the e-cigarettes and liquid flavorings (e-liquids) used in these products are not disclosed, and the potential for exposure to toxic compounds via use of these products is significant. Reported herein is an analysis of the components of e-cigarettes as well as of three popular e-liquids via gas chromatography – mass spectrometry. These results show that components of the e-cigarette contain large quantities of aromatic compounds, and that the e-liquids contain smaller quantities of potentially concerning additives. Most notably, 96% of the extract from the filter was composed of benzyl chloride, a potent DNA alkylating agent, a result which should be of significant concern to consumers, regulatory agencies, and e-cigarette manufacturers. [ABSTRACT FROM AUTHOR]

We describe a copper‐catalyzed Sonogashira coupling reaction of alkyl halides with terminal alkynes under ambient conditions, efficiently providing a versatile tool for the construction of substituted alkynes. A new proline‐based N,N,P‐ligand is utilized to promote the transformation under a mild reaction condition. Diverse alkyl halides, such as primary and secondary (hetero)benzyl chlorides and bromides, secondary and tertiary α‐bromo amides and propargylic bromide, are applicable to provide a wide array of alkynes. [ABSTRACT FROM AUTHOR]

We report a magnetically separable Cu nanocatalyst (Fe-DOPA-Cu) for the borylation of alkyl halides with alkoxy diboron reagents, providing alkylboronic esters in high yields, with broad functional group tolerance under mild reaction conditions. The procedure is also applicable to the borylation of benzyl chlorides and bromides. Radical clock experiments support a radical-mediated process. Easy recycling of the catalyst resulted in no significant loss of activity up to ten runs. [ABSTRACT FROM AUTHOR]

• adipic acid synthesis from cyclohexene and hydrogen peroxide in microemulsion is investigated. • stearyl dimethyl benzyl ammonium chloride is used as surfactant. • reaction carried out without organic ligand and without phase transfer catalyst. • non-polluting catalyst sodium tungstate, which contains no heavy metal, is used. • by recycling the catalyst and the surfactant, the process becomes truly green. Adipic acid appears as an intermediate compound for the synthesis of polyamides and preferentially for the production of nylon-6,6 polyamide. It can be synthesized by the oxidation of cyclohexene by hydrogen peroxide in microemulsion media which has the main advantage to lead a better contact between the two phases thus increasing the yield of the reaction. The microemulsion is generated by stearyl dimethyl benzyl ammonium chloride (C18) as a surfactant avoiding the use of harmful organic solvents and phase-transfer catalysts. The reaction is performed under mild conditions (85 °C, 8 h) with sodium tungstate, - a no heavy metal catalyst - leading to the production of adipic acid in high yield (>80%). By recycling the catalyst and the surfactant, the process becomes truly green. [ABSTRACT FROM AUTHOR]

An easy and efficient synthetic protocol has been developed for the synthesis of 2-substituted-6-Chloro-quinoxalines by the reaction of 2,6-Dichloroquinoxaline with different alcohols, thiols and amine using Tri Ethyl Benzyl Ammonium Chloride (TEBAC). The newly synthesized compounds characterized by spectral data such as IR, ¹HNMR, 13CNMR and mass spectrometry. The compounds were screened for their in vitro antibacterial activity against four different organisms, resulted in the compounds showed good antibacterial activities. [ABSTRACT FROM AUTHOR]

Keywords: Thioflavanones, Condensation, 6-Endo cyclization EN Thioflavanones, Condensation, 6-Endo cyclization 484 487 4 04/20/20 20200401 NES 200401 GLO:1CJF/01apr20:bkcs11989-toc-0001.jpg PHOTO (COLOR): . gl Thioflavanones have a skeleton of a thiochroman-4-one ring with aryl groups in the 2-position and unlike flavanones are not found naturally. Initially, 1-(2-benzylthio)phenylethanone ( B 2 b ) was prepared in two steps: (1) The reaction of 2-mercaptobenzoic acid ( B 1 b ) and 3 equiv. of methyllithium in THF afforded 2'-mercaptoacetophenone in 81% yield. The cyclization of B 3h b with CF SB 3 sb COOH solvent and 5 equiv. of 70% HClO SB 4 sb in THF afforded 4'-methoxythioflavanone ( B 4 h b ) in 90% and 45% yield, respectively, in 4 h/70 °C and 24 h/65 °C, respectively (entries 2-3). On the other hand, the cyclization of B 3h b proceeded well with 1.5 equiv. of 48% HBr in CH SB 3 sb CN to give B 4h b in 93% yield after 1 h at 70 °C (entry 4). [Extracted from the article]