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The asymmetric unit of the title salt, C7H8N3 + ·C7H5O6S- comprises two 1,3- dihydro-2H-benzimidazol-2-iminium cations and two 2-hydroxy-5-sulfobenzoate anions (Z' = 2). In the crystal, the molecules interact through N—H...O, O—H...O hydrogen bonds and C—O...π contacts. The hydrogen bonding interactions lead to the formation of layers parallel to (101). Hirshfield surface analysis revealed that H...H contacts contribute to most of the crystal packing with 38.9%, followed by H...O contacts with 36.2% [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title salt, C7H8N3+·C7H5O6S−, comprises two 1,3-dihydro-2H-benzimidazol-2-iminium cations and two 2-hydroxy-5-sulfobenzoate anions (Z′ = 2). In the crystal, the molecules interact through N—H...O, O—H...O hydrogen bonds and C—O...π contacts. The hydrogen-bonding interactions lead to the formation of layers parallel to (\overline{1}01). Hirshfeld surface analysis revealed that H...H contacts contribute to most of the crystal packing with 38.9%, followed by H...O contacts with 36.2%.

N-heterocyclic carbenes (NHCs) are a versatile class of ligands that have been widely applied in transition metal catalysis. However, NHCs are soft bases, and as such, complexes of NHCs with hard acids—such as many first-row transition metals—are typically sensitive to air and moisture, hence requiring multistep preparations. In this work, two examples of rare copper (II)-NHC complexes were prepared directly from 1,3-bis(pyridylmethyl)imidazolium chloride and 1,3-bis(2-pyridylmethyl)benzimidazolium chloride in protic conditions with no effort to exclude air or moisture. X-ray crystallographic analysis showed that both species display distorted square pyramidal geometry. A probe reaction demonstrated both complexes displayed poor catalytic activity for Chan–Evans–Lam coupling reactions. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are a potential platform for carbon dioxide (CO2) conversion owing to their periodic permanent porosity, adjustable structure, and chemical stability. For good catalytic performance in CO2 conversion, collaborative multifunctions should be strategically integrated into the catalytic system design and construction. In this study, a four-in-one high-efficiency catalyst was synthesized and tested for CO2 cycloaddition to form cyclic carbonate. The obtained Tp-MPB-Br-COF had a high nitrogen content, which enhanced its CO2 affinity through substantial Lewis acid-base or dipole-quadrupole interactions; moreover, the acid (protons transferring from oxygen (–OH) to nitrogen (–NH)), hydrogen bond donor (hydroxyl group), and Br− (nucleophile group) served as three active sites, further improving the catalyst activity. These results provide a basis for designing efficient and stable CO2-conversion catalysts. [ABSTRACT FROM AUTHOR]

The present work centered attention on novel ionic liquid (IL) based on dicationic benzimidazolium ion containing amide group (DBimIL) synthesized using dialkylation of N-ethyl benzimidazole to followed with anion exchange reaction. To explore the potential application of ILs, there is a great need to grasp their structural and physical properties. We have developed three different set of DBimIL based ionic liquids with chloride, hexafluorophosphate and perchlorate anions in aqueous media, respectively. Their structural features were studied using 1H, 13C-NMR, FTIR, and HRMS spectroscopy, respectively. The temperature-dependent dielectric characteristics of ILs were closely examined angular frequency in the range of 0.6–125 rad/s from 30 to 150 °C. The relationship between the structural and dielectric properties of ILs established. The dielectric parameters like dielectric constant, dissipation factor and the real part of ac conductivity were found to be affected significantly with the tuning of anionic moieties of ionic liquids. The ability of materials to store a charge in electromagnetic field was measured. From dielectric and electrical studies, to bring to an end, especially in particular way that the present IL systems have an enormous potential for the designing of modern-day energy storage devices. [ABSTRACT FROM AUTHOR]

Owing to the broad applications of quaternary ammonium salts (QAS), we present the synthesis of benzimidazolium-based analogues with variation in the alkyl and alkoxy group at N-1 and N-3 positions. All the compounds were characterized by spectroscopic techniques and found stable to air and moisture both in the solid and solution state. Moreover, molecular structures were established through single-crystal X-ray diffraction studies. The crystal packing of the compounds was stabilized by numerous intermolecular interactions explored by Hirshfeld surface analysis. The enrichment ratio was calculated for the pairs of chemical species to acquire the highest propensity to form contacts. Void analysis was carried out to check the mechanical response of the compounds. Furthermore, theoretical investigations were also performed to explore the optoelectronic properties of compounds. Natural population analysis (NPA) has been conducted to evaluate the distribution of charges on the synthesized compounds, whereas high band gaps of the synthesized compounds by frontier molecular orbital (FMO) analysis indicated their stability. Nonlinear optical (NLO) analysis revealed that the synthesized QAS demonstrates significantly improved NLO behaviour than the standard urea.

Due to the synergistic effect of central metal and halide anion, cationic metalloporphyrins and derivatives exhibit outstanding catalytic activities for the cycloaddition reaction of epoxides and carbon dioxide. Herein, a generic strategy was developed to synthesize the benzimidazolium‐containing metalloporphyrin molecule and polymer. To demonstrate the method feasibility, we firstly synthesized the molecule 1H, in which the benzimidazole groups were in‐site constructed by the cyclization of 5,10,15,20‐(4‐carboxyphenyl)‐porphyrin (H2TCPP) with o‐diaminobenzene (PEA). After post‐synthetic ionization and metallization, I− and Zn2+ were introduced as the nucleophile and Lewis acid, respectively. The structure of 1ZnIL was confirmed by single crystal X‐ray diffraction analysis. By using the similar conditions of model reaction, H2TCPP was copolymerized with 1,2,4,5‐tetraaminobenzene (BTA) to prepare the polymer P‐1ZnIL. The prepared cationic molecule 1ZnIL and polymer P‐1ZnIL showed comparable activities in catalyzing the cycloaddition of carbon dioxide with epoxides to cyclic carbonates compared to the reported bifunctional catalysts based on metalloporphyrins. [ABSTRACT FROM AUTHOR]

The main problems experienced in treatment with anticancer drugs are undesirable side effects, and toxicity. Minimal side effects for new anticancer compounds may be met due to enhanced efforts to clarify the compound's mechanisms of action. Therefore, we aimed to investigate whether or the cytotoxic effect and apoptosis mechanism of a series Ag(I)NHC complexes on non-small cell lung cancer cell line (A549) and normal lung fibroblast cell line (CCD-19Lu) in this study. The cytotoxicity was determined by using the MTT method, and apoptotic effects were detected by cell cycle, annexin-V/propidium iodide (PI) staining and cell cycle, caspase-3, mitochondrial membrane potential analysis. Molecular docking studies were performed using in silico ADMET analysis, and molecular docking information on the compounds was gained using the DS 3.5 software subprotocol. All the time, the cytotoxic effect of silver compounds was monitored for 24 h in comparison to cisplatin. The apoptotic effect of these compounds increased in cancer cells as compared to normal cells. Complex 3b exhibited the highest cytotoxic activity on cancer cell in 24 and 72 h, but complex 3a exhibited the highest cytotoxic activity on cancer cell s in 48 h. Moreover, all Ag(I)NHC complexes exhibited significant statistical difference depending on the increase in concentration on cancer cells, and all compounds induced apoptosis associated with distributing of membrane polarization and stopping the cell cycle in phase G1 and the caspase-3 activity. Caspase-3 activity of the new Ag(I)NHC compounds showed 8.3 to 17.6-fold increase compared the untreated cells. The loss of mitochondrial membrane potential indicated that JC-1 assay results were 16.9 to17.2-fold higher than normal cells in Ag(I)NHC compounds and 11.3-fold higher her in cisplatin. In addition, molecular docking studies were executed on the Ag(I)NHC complexes, and cisplatin estimate that the binding modes towards the EGFR kinase. Because epidermal growth factor receptor (EGFR) is expressed highly in a great number of epithelial tumors. These findings suggested that Ag(I)NHC complexes exhibited anticancer activity and may be considered to have a new therapeutic potential for human non-small cell lung cancer cell treatment. [ABSTRACT FROM AUTHOR]

Purpose: Leishmaniasis is a serious public health problem infecting millions of people worldwide. An effective and reliable treatment method to be used in the treatment of the disease has not been developed yet. Methods: In this article, the anti-leishmanial activities of two benzimidazolium derivatives (B.A and B.B) against Leishmania major promastigotes and amastigotes, which are known to cause cutaneous leishmaniasis, were investigated for the first time. The immunostimulatory activity of the developed formulations was determined using the J774 murine macrophage cell line. Results: B.A and B.B compounds were found to have a much higher cytotoxic effect than Amphotericin B (IC50 value 0.75 μM ± 0.03), which is used as the reference drug. The IC50 value was determined as 2.02 µM ± 0.52 for B.A and 1.83 µM ± 0.71 for B.B in Leishmania promastigotes. In addition, IC50 values of B. A and B.B Leishmania amastigotes were found to be 1.01 µM and 0.67 µM, respectively. It was found that B.B was 81.12 times more selective than Amphotericin B and showed the highest selectivity against L. major promastigotes (359.09) and amastigotes (980.80). Considering the selectivity indices (SI) of B.A and B.B, both compounds tested are more promising than Amphotericin B. Conclusion: The results showed that benzimidazolium derivatives have anti-leishmanial potential against L. major, which is the causative agent of cutaneous leishmaniasis. Thus, we can say that the obtained results will help the development of effective and safe antileishmanial drug formulations against cutaneous leishmaniasis. [ABSTRACT FROM AUTHOR]

1,3‐Bis(benzimidazoliumyl)benzene‐based chalcogen‐bonding catalysts were previously successfully applied in different benchmark reactions. In one of those examples, i.e. the activation of quinolines, sulfur‐ and selenium‐based chalcogen‐bonding catalysts showed comparable properties, which is unexpected, as the selenium‐containing catalysts should show superior catalytic properties due to the increased polarizability of selenium compared to sulfur. Herein, we present four crystal structures of the respective 1,3‐bis(benzimidazoliumyl)benzene‐based chalcogen‐bonding catalyst containing sulfur (3S) and selenium (3Se, three forms) as Lewis acidic centres. The sulfur‐containing catalyst shows weaker chalcogen bonding compared to its selenium analogue, as well as anion–π interactions. The selenium‐based analogues, on the other hand, show stronger chalcogen‐bonding motifs compared to the sulfur equivalent, depending on the crystallization conditions, but in every case, the intermolecular interactions are comparable in strength. Other interactions, such as hydrogen bonding and anion–π, were also observed, but in the latter case, the interaction distances are longer compared to those of the sulfur‐based equivalent. The solid‐state structures could not further explain the high catalytic activity of the sulfur‐containing catalysts. Therefore, a comparison of their σ‐hole depths from density functional theory (DFT) gas‐phase calculations was performed, which are again in line with the previously found properties in the solid‐state structures. [ABSTRACT FROM AUTHOR]

A new benzimidazolium salt (1-Allyl-3-(2,3,5,6-tetramethylbenzyl)-5,6-dimethylbenzimidazoliumchloride) is characterized by using 1H NMR and 13C(1H) NMR spectroscopies. The corrosion inhibition performance of benzimidazolium salt for mild steel in an acidic medium is investigated with the help of both experimental and theoretical tools. The experimental part of inhibition analysis includes the use of electrochemical impedance spectroscopy (EIS), linear sweep voltammetry, potentiodynamic polarization techniques, and surface characterizations are made. In the theoretical part, Density Functional Theory calculations are performed to discuss the corrosion inhibition efficiency using quantum chemical parameters. Molecular Dynamic Simulation calculation is made to analyze adsorption properties and characteristics of synthesized molecules on mild steel. Experimental studies show that the inhibition efficiency is calculated as 97.6% from EIS results for 5 × 10−3 M inhibitor. Both experimental analyses and theoretical calculations proved that the studied inhibitor molecule is exhibiting higher inhibition efficiency. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a parasitic disease affecting more than 12 million people worldwide. Although the use of chemotherapeutic drugs is among the current treatment methods, it is emphasized that the limitations of the drugs, their disadvantages such as insufficient safety and efficacy, the disease being endemic, and the need to develop drugs for this disease. In this study, in vitro anti-leishmanial activities of two benzimidazole derivatives (B1 and B2) were tested against L. infantum promastigote and amastigote for the first time. In our study, the anti-leishmanial effects of B1 and B2 on both amastigote and promastigote forms of Leishmania infantum were investigated using J774 macrophage cells. It was found that the tested compounds were not toxic to the host cell. In addition, when compared to the drug miltefosine, which is used worldwide in the treatment of leishmaniasis, it has been determined that it has a serious inhibitory effect by reducing the proliferation of promastigotes and the metabolic activities of amastigotes, and it acts at lower concentrations than miltefosine. We found that benzimidazolium derivatives (B1 and B2) used for the first time in this study were more effective on both forms of L. infantum. The obtained results showed that benzimidazolium derivatives have high anti-leishmanial potential against L. infantum, which is the cause of Visceral Leishmaniasis (VL), which is known to be the deadly form of leishmaniasis. It has been shown that the obtained results will help the development of safe, stable, and effective anti-leishmanial drug formulations against VL. [ABSTRACT FROM AUTHOR]

N-heterocyclic carbene molecules are often used as the main scaffold in pharmaceutical chemistry, and one of the most important of these is benzimidazoles. Severe Acute Respiratory Syndrome Coronavirus Disease-2 is the cause of the ongoing pandemic, and a drug should be developed against this virus. Scientists have been investigated the antiviral effects of many not only known molecules but also new molecules. In this study, reactivity and anti-coronavirus disease properties of new benzimidazole derivative molecules were investigated by theoretical methods. Three new benzimidazole derivative molecules were synthesized and fully characterized by FT-IR, ¹H NMR and, 13C{¹H} NMR spectroscopies for this purpose. Density Functional Theory-based calculation methods were used for optimization and frontier orbitals analysis. Also, the interactions of the molecules were evaluated with coronavirus disease main protease, and severe acute respiratory syndrome coronavirus main peptidase and the results were compared with the results of well-known anti-viral drugs by molecular docking methods. According to the results, 1-allyl-3-(3-chlorobenzyl-5,6-dimethylbenzimidazolium chloride represent the best result against both main protease and main peptidase enzyme with -6.36 kcal/mol and -8.87 kcal/mol, respectively. Additionally, three of the molecules were give better binding results than the well-known anti-viral drugs. [ABSTRACT FROM AUTHOR]

N-heterocyclic carbene molecules are often used as the main scaffold in pharmaceutical chemistry, and one of the most important of these is benzimidazoles. Severe Acute Respiratory Syndrome Coronavirus Disease-2 is the cause of the ongoing pandemic, and a drug should be developed against this virus. Scientists have been investigated the antiviral effects of many not only known molecules but also new molecules. In this study, reactivity and anti-coronavirus disease properties of new benzimidazole derivative molecules were investigated by theoretical methods. Three new benzimidazole derivative molecules were synthesized and fully characterized by FT-IR, 1H NMR and, 13C{1H} NMR spectroscopies for this purpose. Density Functional Theory-based calculation methods were used for optimization and frontier orbitals analysis. Also, the interactions of the molecules were evaluated with coronavirus disease main protease, and severe acute respiratory syndrome coronavirus main peptidase and the results were compared with the results of well-known anti-viral drugs by molecular docking methods. According to the results, 1-allyl-3-(3-chlorobenzyl-5,6-dimethylbenzimidazolium chloride represent the best result against both main protease and main peptidase enzyme with -6.36 kcal/mol and -8.87 kcal/mol, respectively. Additionally, three of the molecules were give better binding results than the well-known anti-viral drugs.

Cystic Fibrosis (CF) results from the loss of function of the cystic fibrosis transmembrane conductance regulator (CFTR), an ion channel of key importance in the airway epithelia. CFTR helps control optimal hydration of the airways, a crucial requirement for healthy lungs. CFTR modulators have recently been approved as an effective treatment option for many genetic variants of CF. The epithelial sodium channel (ENaC), unlike CFTR which is secretory, is an absorptive pathway, and therefore its inhibition is an alternative and potentially complementary approach to aid hydration of the airways. Due to the adverse effect of ENaC inhibition in the kidney we, as have several others, focused on the design and synthesis of novel ENaC inhibitors for direct delivery to the airways via inhalation. A new series of ENaC inhibitors is described, wherein the well-established pyrazine core of first-generation inhibitors was replaced with a pyrrolopyrazine. Aiming for high retention at the surface of the lung following inhalation, optimisation of this template focused on significantly increasing polarity to minimize passive cellular permeability. The resulting optimized clinical candidate ETD001 demonstrates potent inhibition of ENaC (59 nM) prolonged retention in the airways of rats (13 % of the delivered dose retained after 6h) following intratracheal administration and a potent and long-acting effect in a sheep model of mucociliary clearance following inhalation (ED 100 (4–6h) = 9 μg/kg). ETD001 entered a phase II study in CF patients in July 2024. [Display omitted] • A series of ENaC inhibitors with a novel pyrrolopyrazine core is described. • Increasing molecular polarity correlated with improved airway retention. • This work led to the selection of ETD001 for clinical development. • ETD001 entered a Phase II clinical study in CF patients in 2024. [ABSTRACT FROM AUTHOR]

The organic-inorganic complex salt, (C8H10N3)3[La(NO3)6], comprises a network of N-protonated 2-amino-1-methylbenzimidazolium cations and hexakis(nitrato)lanthanate(III) anions. The LaIII atom is twelve-coordinate within a distorted icosahedral environment. In the unit cell, each pair of the LaIII atoms lie nearly on one of the crystallographic glide planes. In the crystal structure, there are several N--H...O hydrogen-bonding interactions between the cations and terminal oxygen atoms from the nitrate moieties of the [La(NO3)6]3-anion. Additional weak C--H...O hydrogen bonds between the cations and anions consolidate the three-dimensional arrangement of the structure. A packing analysis was performed to check the strength of the crystal packing. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the antimicrobial, antibiofilm, and cytotoxicity properties of methallyl substituted benzimidazolium-based, silver-bound N-heterocyclic carbene (Ag(I)-NHC) complexes, with respect to their potential to act as antimicrobial agents. Methods: The antimicrobial, antibiofilm, and cytotoxicity properties of the four complexes, the synthesis and characterization of which were carried out previously, were investigated. The antimicrobial properties were tested using the broth microdilution method, while their antibiofilm potential were determined by microtiter plate assay. The L-929 cell line was used for cytotoxic studies. Results: Strong antibiofilm and antimicrobial effects were produced by Ag(I)-NHC complexes. Compounds 2 and 3 showed potent activities against E. coli strain, with effects similar to that of positive control antibiotic, while compounds 1 and 4 exhibited antimicrobial activity at a concentration of 31.2 µg/mL. The compounds were effective against biofilms formed at concentrations in the range of 32 -- 84 %, and degraded mature biofilms at a concentration range of 14 - 66 %. Compounds 1 and 2 did not significantly affect cell survival (p > 0.05), while compounds 3 and 4 significantly reduced cell survival, when compared with untreated cells in the control group (p < 0.001). Conclusion: This study may be one of the few studies on benzimidazolium-derived NHCs. The compounds which produced antimicrobial, antibiofilm, and cytotoxic properties in this study may be valuable and novel antimicrobial agents. Therefore, there is need for further in vivo and in vitro studies on these compounds. [ABSTRACT FROM AUTHOR]

Microorganisms in the biofilm structure cause severe health problems and economic losses. Therefore, it is very important to design and screen anti-biofilm molecules that can solve the related problems. This paper is aimed to demonstrate the antimicrobial and anti-biofilm properties of allyl substituted benzimidazolium-based Ag(I)-containing N-heterocyclic carbene (NHC) complexes. In this work, the antimicrobial and anti-biofilm properties of six allyl-substituted benzimidazolium-based Ag(I)-NHC complexes, the synthesis and characterization of which had been carried out previously, were investigated. The antibacterial properties of Ag(I)-NHC complexes were tested by the broth microdilution method. The biofilm formation was detected by microtiter plate assay. All test compounds (1–6) showed strong and same activity against Escherichia coli ATCC 25922 at concentrations of ≤3.9 μg/mL as compared to that of the reference anti-biotics (ampicillin). Test compounds exhibited the same or stronger activity than the reference drug against the Acinetobacter baumannii isolate with MedIC values of 15.6 – 31.25 μg/mL in comparison to the positive control colistin. All compounds inhibited the formation of E. coli biofilms at sub-MIC concentrations by 56 – 90%. Furthermore, it was found that these compounds reduced Klebsiella pneumoniae biofilm formation by 29 – 65%, S. aureus biofilm formation by 36 – 52%, E. faecalis biofilm formation by 38 – 50%, A. baumannii biofilm formation by 51 – 60%, and Candida albicans biofilm formation by 38 – 53%. Regarding the biofilms formed, it was established that the test compounds eradicated the mature of E. coli biofilm by 43 – 63%, K. pneumoniae biofilm by 16 – 40%, S. aureus biofilm by 18 – 39%, E. faecalis biofilm by 15 – 27%, A. baumannii biofilm by 27 – 53%, and C. albicans biofilm by 18 – 41%. Compounds evaluated in our work, which is one of the few studies on benzimidazolium-derived NHCs, have the potential to become new biological agents with strong antimicrobial properties and activity against microbial biofilms. Therefore, further in vivo and in vitro studies should be conducted. [ABSTRACT FROM AUTHOR]

In this work, a novel compound, 1-(2,5-dimethylbenzyl)benzimidazole (1) was prepared by N-alkylation of benzimidazole with 2,5-dimethylbenzyl chloride in the presence of KOH base. Quaternization of 1 with 2,5-dimethylbenzyl chloride gave 1,3-bis(2,5- dimethylbenzyl)benzimidazolium chloride (2) salt. The reaction of 2 with palladium(II) acetate, PPh3, LiCl and Et3N gave [PdCl2{1,3-bis(2,5-dimethylbenzyl)benzimidazolin-2-ylidene}(PPh3)] (3) complex. The prepared compounds were characterized by spectroscopic methods and elemental analysis. The palladium complex 3 was used as catalyst in Suzuki-Miyaura cross-coupling reactions of some aryl bromides and chlorides with phenylboronic acid. In the reactions of the all aryl bromides, the catalyst displayed excellent activity and biphenyl compounds were achieved in >99% yields. High activity was observed with some aryl chlorides. [ABSTRACT FROM AUTHOR]

Hybrid 2-(2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)vinyl)-1,3-dimethyl-1H-benzo[d]imidazol-3-ium iodide compounds (LHZD-1 ∼ 3) were synthesized by Knoevenagel condensation reaction. Their structures were confirmed by 1H NMR, 13C NMR and HRMS spectroscopy. The fluorescence property of LHZD-1 ∼ 3 varied with the substituent groups such as -Br, -H and -OMe in the benzimidazolium skeleton. The probe LHZD-1 showed remarkable selectivity for the bisulfite ion over other common anions and biotins, which outputted the obvious color change in both absorption (462 nm to 400 nm) and emission (580 nm to 480 nm) spectra. The probe LHZD-1 showed the lysosome positioning action in Hela cells. This study not only provides a way for optimizing coumarin-benzimidazolium probes but also holds considerable promise in detection of bisulfite ion in organelles. [ABSTRACT FROM AUTHOR]

In the present study, a novel task-specific benzimidazolium ionic liquid with silyl substitution was synthesised and successfully introduced as a corrosion inhibitor. The inhibitory effect of 2-benzyl-1-butyl-3-(3-(triethoxysilyl)propyl)-1H-benzo[d]imidazolium chloride (BTOSPB) in HCl solution on steel corrosion was evaluated by electrochemical measurement and surface studies including scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy (XPS). XPS and EDX results prove the presence of BTOSPB in the formed film on the metal surface, and its binding to the surface. Electrochemical impedance investigations indicated the prominent inhibitive performance of BTOSPB with an efficiency of 99.6%. According to the polarisation curves, BTOSPB is a mixed-type inhibitor with higher efficiency at higher temperatures and higher corrosive environment acidity. The results indicate that excellent inhibition efficiency was attained even in harsh conditions such as elevated temperature, long exposure time, and harder acidity of the solution. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and antibacterial studies of N-heterocyclic carbene (NHC) precursors and their respective silver(I)-NHC complexes are reported. Five non-symmetric benzimidazolium bromide salts were synthesized through the addition of N-alkylbenzimidazole and various alkylbromides. These n-butyl-n'-alkylbenzimidazolium bromide salts (alkyl = methyl, ethyl, pentyl, hexyl, heptyl) 1, 2 and 4–6 were further used as precursors to synthesize silver(I)-NHC complexes, 8, 9 and 11–13, respectively, via in situ deprotonation. In addition, 14 was synthesized from its reported precursor salt, 1-benzyl-3-butylbenzimidazolium bromide (7) through the same procedure. Complex 8 is present as monomeric cation in the form of [NHC-Ag-NHC]PF6, as illustrated by single crystal X-ray crystallography analyses. In order for a full series of antibacterial studies, 1-butyl-3-propylbenzimidazolium bromide, 3, and respective complex, 9, were synthesized according to the reported procedure. All benzimidazolium salts (1–7) and silver(I)-NHC complexes (8–14) were evaluated for antibacterial activities. All benzimidazolium salts show no antibacterial activities while all silver(I)-NHC complexes show lower activities against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 12600) compared to the standard antibiotic drug Amoxicillin. Nevertheless, these mononuclear silver(I)-NHC complexes show lower antibacterial activities compared to the reported dinuclear silver(I)-NHC complexes with the same substituents in the ligands. [ABSTRACT FROM AUTHOR]

A series of ester-functionalized benzimidazolium salts 2a–c were prepared by quaternization of 1-{(ethoxycarbonyl)methyl}benzimidazole (1) with 3,5-dimethylbenzyl bromide, 2,5-dimethylbenzyl chloride and 3-methoxybenzyl chloride, respectively. Refluxing 2a–c with nickelocene in THF yielded the neutral cyclopentadienyl NHC nickel(II) complexes 3a–c. Their structures were defined by NMR, IR and elemental analysis techniques. Molecular weights of 3a–c were affirmed by MALDI-TOF mass spectrometry. Catalytic tests of 3a–c were performed in Kumada coupling of some aryl chlorides with phenylmagnesium bromide at 25 °C. [ABSTRACT FROM AUTHOR]

A polymer-supported Brønsted acid-functionalized Zn–porphyrin complex, knotted with benzimidazolium moiety (PSBAZnPP), has been synthesized and characterized by Fourier transform nuclear magnetic resonance (FT-NMR) and Fourier transform infrared spectroscopy (FTIR). The thermal stability was determined by thermogravimetric analysis (TGA), and surface morphology and elemental composition were investigated by scanning electron microscopy and energy-dispersive spectroscopy (SEM/EDAX). The heterogeneous PSBAZnPP showed high efficacy as a photocatalyst for degradation of azo dyes, such as methyl red (MR), methyl orange (MO) and Congo red (CR), in the presence of visible-light irradiation at ambient condition using atmospheric air/H2O2. The concentration of the dyes was measured by UV–visible spectroscopy, and the degradation of the dyes was confirmed by GC–MS analysis. Further decolorization and degradation of MO were confirmed by using ultra-high-pressure liquid chromatography (UPLC). The optimum degradation was achieved by adding 10 mg catalyst for all azo dyes for 60 min in the presence of air. The effect of scavengers was studied to indicate the most active species generated during photocatalysis. PSBAZnPP furnished a good response toward the photodegradation of MR, MO and CR under optimized conditions. Finally, the mechanism of photocatalytic degradation process was suggested. Relevant active species produced in the PSBAZnPP/H2O2 or PSBAZnPP/air system under visible light were recognized by using different types of scavengers, viz. EDTA, p-benzoquinone (PBQ), terephthalic acid (TPA), sodium azide and sodium nitrate, for determination of formation of holes, O 2 · , OH · , 1 O 2 and an aqueous electron (e−), respectively. The comparative acidity of the synthesized PSBAZnPP catalyst was measured using UV–Vis and then equated to relations of the Hammett value (H0). The efficiency of catalyst correlates with a considerable proton level required for degradation of organic dyes. [ABSTRACT FROM AUTHOR]

A series of novel N-heterocyclic carbene rhodium complexes (NHC-Rh), containing benzimidazole framework, were prepared smoothly by a five-step route. Their structures were elucidated based on spectral techniques, including NMR and MS spectrometry. Along with several NHC-Rh complexes we prepared before, the compounds prepared herein were evaluated for their cytotoxicities against MCF human breast cancer cells and several of them showed strong activities with IC50 values ranging from 0.38 to 1.18µM, which were better than the positive control paclitaxel. [ABSTRACT FROM AUTHOR]

Lung selective inhibition of the endothelial sodium channel (ENaC) is a potential mutation agnostic treatment of Cystic Fibrosis (CF). We describe the discovery and development of BI 1265162, the first ENaC inhibitor devoid of the amiloride structural motif that entered clinical trials. The design of BI 1265162 focused on its suitability for inhalation via the Respimat® Soft Mist™ Inhaler and a long duration of action. A convergent and scalable route for the synthesis of BI 1265162 as dihydrogen phosphate salt is presented, that was applied to support clinical trials. A phase 2 study with BI 1265162 did not provide a clear sign of clinical benefit. Whether ENaC inhibition will be able to hold its promise for CF patients remains an open question. [Display omitted] • First ENaC inhibitor in clinical development devoid of Amiloride structure. • Permanently charged benzimidazolium scaffold compatible with high selectivity. • Scalable synthesis route developed for crystalline salt form of BI 1265162. • In vivo tool compound and inactive analog designed and made available. [ABSTRACT FROM AUTHOR]

Owing to the broad applications of quaternary ammonium salts (QAS), we present the synthesis of benzimidazolium-based analogues with variation in the alkyl and alkoxy group at N-1 and N-3 positions. All the compounds were characterized by spectroscopic techniques and found stable to air and moisture both in the solid and solution state. Moreover, molecular structures were established through single-crystal X-ray diffraction studies. The crystal packing of the compounds was stabilized by numerous intermolecular interactions explored by Hirshfeld surface analysis. The enrichment ratio was calculated for the pairs of chemical species to acquire the highest propensity to form contacts. Void analysis was carried out to check the mechanical response of the compounds. Furthermore, theoretical investigations were also performed to explore the optoelectronic properties of compounds. Natural population analysis (NPA) has been conducted to evaluate the distribution of charges on the synthesized compounds, whereas high band gaps of the synthesized compounds by frontier molecular orbital (FMO) analysis indicated their stability. Nonlinear optical (NLO) analysis revealed that the synthesized QAS demonstrates significantly improved NLO behaviour than the standard urea., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)

Abstract A new N-heterocyclic carbene (NHC) salt was synthesized by the reaction of 1-allyl benzimidazole with 2-methyl benzyl chloride. The structure of N-heterocyclic carbene salt was determined by elemental analysis, FT-IR, 1 H NMR and 13 C NMR spectroscopy and supported by the computational spectral analyses. For this purpose, the stable conformational structures obtained by Potential Energy Surface (PES) scan at B3LYP/6-31G (d,p) level of the theory have been used to elucidate the spectroscopic studies of the NHC salt as well as to search the electronic properties being important to predict the chemical reactivity behavior and nonlinearity properties of the NHC salt. FMO amplitudes and MEP diagrams have been used to show the chemically active sites of each stable conformer. Graphical abstract Image 1 Highlights • Synthesis and characterization of the NHC salt. • The structure was investigated by NM and FT-IR spectroscopy. • Stable conformers of NHC salt were revealed by computational modeling. • Spectral data were compared with computational ones. • NBO, NLO, FMO and MEP diagrams were investigated by computational tools. [ABSTRACT FROM AUTHOR]

[Display omitted] • The benzimidazolium Gemini surface active ionic liquid could strongly reduce the system interfacial tension. • Synergisms of 97.6 and 83.9% in interfacial tension and critical micelle concentration reductions with mixtures. • Mixtures could create stable dispersions of crude oil in water and alter the wettability. • Reproducing the interfacial tension data with theories of Frumkin and non-ideal interactions in binary mixtures. • Mixtures of benzimidazolium Gemini surface active ionic liquid work stronger than those of imidazolium ionic liquid. The high price of newly explored surfactants is a concern in applications, but their mixture with conventional surfactants can bring about desired outcomes. Gemini surface active ionic liquids (GSAILs) have emerged as unique materials in tuning interface properties. Surfactants like sodium dodecyl sulfate (SDS), on the other hand, are known effective and commercially available. This study investigates the simultaneous effects of a benzimidazolium cationic GSAIL, [C 4 benzim-C 6 -benzimC 4 ][Br 2 ], and SDS surfactants on the interfacial tension (IFT), emulsification, and wettability alteration of the crude oil−water system. The results demonstrate amazing synergies up to 97.6 % in the IFT reduction. An ultra-low IFT of 0.16 mN·m−1 was achieved with an optimum GSAIL mole fraction of 0.4, attributed to the attractive interaction between the cationic GSAIL and the anionic SDS. Mixtures also give 54.3 and 72.8 % synergies in emulsification and wettability alteration, respectively. The adsorption of individual and mixture of surfactants were theoretically analyzed using the Frumkin adsorption isotherm and the non-ideal interactions of the binary mixtures (NIBM) theory. The corresponding determined parameters were consistent. To have a more comprehensive analysis, the results were compared with those obtained with an analogous structure imidazolium GSAIL. [ABSTRACT FROM AUTHOR]

Abstract Two new benzimidazolium salts with the same cationic moiety and different anions 3-(2′-((8″-hydroxy-9″,10″-dioxo-9″,10″-dihydroanthracen-1″-yl)oxy)ethyl)-1-(pyridin-2‴-ylmethyl)-1H-benzo[ d ]imidazol-3-ium bromide and 3-(2′-((8″-hydroxy-9″,10″-dioxo-9″,10″-dihydroanthracen-1″-yl)oxy)ethyl)-1-(pyridin-2‴-ylmethyl)-1H-benzo[ d ]imidazol-3-ium hexafluorophosphate were prepared and characterized. The single crystal structure of 3-(2′-((8″-hydroxy-9″,10″-dioxo-9″,10″-dihydroanthracen-1″-yl)oxy)ethyl)-1-(pyridin-2‴-ylmethyl)-1H-benzo[ d ]imidazol-3-ium bromide was determined by X-ray single crystal diffraction. Particularly, anion recognition using 3-(2′-((8″-hydroxy-9″,10″-dioxo-9″,10″-dihydroanthracen-1″-yl)oxy)ethyl)-1-(pyridin-2‴-ylmethyl)-1H-benzo[ d ]imidazol-3-ium hexafluorophosphate as a chemosensor was carried out via fluorescence and ultraviolet spectroscopy, 1H NMR titrations, HRMS and IR spectra. The response of this chemosensor to fluoride anion can be observed through both remarkable fluorescence quenching and color change under visible light (from orange to purple). The results indicated that this chemosensor can distinguish fluoride anion from other anions via the instrument and naked eyes, and this is greatly convenient in practical operation. Graphical abstract Benzimidazolium salts 2 and 3 were synthesized and characterized, and the recognition of 3 for F− was studied via fluorescence and ultraviolet spectroscopy. Image 1 [ABSTRACT FROM AUTHOR]

Abstract The dominance of multi drug resistance in the clinically significant bacteria led to urgency in the development of new antibiotics with novel mechanism of action. Among the biochemical targets explored for selective toxicity, molecular mechanisms involving cell division remained focal point for novel antimicrobial drug discovery. For this purpose we have performed in-silico studies of FtsZ protein and obtained benzimidazolium compounds as potential hits. These molecules obtained in the dock results were synthesized via reacting benzimidazoles with appropriate benzyl halides. The structures of the synthesized compounds were confirmed by their 1H NMR, 13C NMR, IR and mass spectral data. These were evaluated for anti-microbial activity. Among the tested compounds B14, B15 and B20 have shown highest activity (MIC 5 μg/mL) against Staphylococcus aureus , Macrococcus caseolyticus, Escherichia coli and Pseudomonas aeruginosa.. Microscopic examination of drug-treated cultures of Staphylococcus aureus and Pseudomonas aeruginosa showed rod-shaped filamentous growth of the dividing cells, which is a characteristic feature of FtsZ inhibition. Graphical abstract Image 1 Highlights • Novel FtsZ enzyme inhibitors with benzimidazole nucleus were designed and then docking analysis was carried out. • Hit molecules were synthesized and structures were confirmed by IR, NMR and Mass spectra. • They are evaluated for antimicrobial activity and anti fungal activity. • Cell divison inhibitory assay was performed as a proof of concept that it acts on FtsZ protein. [ABSTRACT FROM AUTHOR]

Abstract: Esters of levulinic acid (LA) are bio-based compounds having widespread applications and have the remarkable potential to be blended with commercial diesel or gasoline. In this study, a sulphonic acid-functionalized benzimidazolium based poly ionic liquid (SAFBPIL) catalyst was prepared and characterized by NMR, FT-IR, elemental analysis (C, H, N, S), TGA and BET surface area. Brønsted acidity was determined by anion-exchange/neutralization titration method and was found to be 5.55 mmol/g. The heterogeneous ionic liquid catalyst showed an excellent thermal stability up to 270 °C. Experiments were carried at different temperatures, LA to ethanol molar ratios, catalyst loadings and duration of the reaction in a batch reactor. The highest conversion was obtained at 70 °C using an initial LA:ethanol molar ratio of 1:10 and a catalyst loading of 15 wt% in 9 h. It was observed that ethyl levulinate (EL) could be effectively obtained over SAFBPIL with a selectivity higher than 99.5%. This is due to more acidic sites exhibited on SAFBPIL catalyst under optimized conditions. Herein, we are reporting for the first time an esterification of LA to EL using a new SAFBPIL as a catalyst. The catalyst was recycled for five runs without significant loss of catalytic activity.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The stability of anion exchange membranes (AEMs) is an important feature of alkaline exchange membrane fuel cells (AEMFCs), which has been extensively studied. However it remains a real challenge due to the harsh working condition. Herein, we developed a novel type of polysulfone-based AEMs with three modified 1,2-dimethylbenzimidazoliums containing different substitutes at C4- and C7-position. The results showed that the introduction of the substitutes could obviously improve the dimensional and alkaline stabilities of the corresponding membranes. The swelling ratios of resultant AEMs were all lower than 10% after water immersion. The membrane with 4,7-dimethoxy-1,2-dimethylbenzimidazolium group exhibited the highest alkaline stability. Only 9.2% loss of hydroxide conductivity was observed after treating the membrane in 1 mol·L KOH solution at 80 °C for 336 h. Furthermore, the density functional theory (DFT) study on the three functional group models showed that the substitutes at C4- and C7-position affected the lowest unoccupied molecular orbital (LUMO) energies of the different 1,2-dimethylbenzimidazolium groups. [ABSTRACT FROM AUTHOR]

• Benzimidazolium salts bearing 4-(methylthio)benzyl group were synthesized. • All compounds were characterized by NMR and FTIR spectroscopic techniques. • One compound was examined by the single-crystal X-ray diffraction method. • Inhibitory effects of all compounds were been tested against XO and AChE enzymes. • Molecular docking work was conducted on the chosen compounds against AChE and XO. The sulfurous compounds are known as organosulfur, which has been associated with numerous biological activities in both natural products and synthetic organic compounds. In this work, we present the synthesis of a series of 4-(methylthio)benzyl substituted benzimidazolium salts. All compounds were characterized using NMR (1H and 13C) and FTIR spectroscopic methods as well as an elemental analysis technique. The molecular and crystal structures of the compound 1a were determined by X-ray crystallography revealing that the compound crystallized in the trigonal space group R-3. Enzyme inhibition studies demonstrated that a new series of sulfurous compounds precursors were highly potent inhibitors for xanthine oxidase (XO) and acetylcholinesterase (AChE) enzyme. The IC 50 values were found in the range of 0.548 ± 0.033 to 0.725 ± 0.043 µM for XO promising strategy for the treatment from gout disease, while IC 50 values were found in the range 0.813 ± 0.076 to 1.149 ± 0.072 µM toward AChE as the key enzyme promising strategy for the treatment of neurological disorders such as Alzheimer's disease (AD). Furthermore, pharmacodynamics studies prove the binding interaction patterns, structural orientations and drug potential of sulfide derivatives in the binding sites of xanthine oxidase (XO) and acetylcholinesterase (AChE) enzymes. Potential inhibitors (compounds 1d-f) were compared with standard compounds allopurinol (for XO) and donepezil (for AChE). Compared to the positive compound of target XO, the 4-vinylbenzyl group of potential compound 1f and the 4-methylbenzyl group of compound le more effectively formed electrostatic and hydrophobic interactions with the target's interaction site. While donepezil as standard compound interacts only at the peripheral anionic site of AChE, the related compounds interact with both regions (PAS and CAS sites) of the same target. These compounds were placed at the active sites of the respective targets by molecular docking method using AutoDock software. Binding energy, binding modes and interaction types were used to evaluate the series of 4-(methylthio)benzyl substituted benzimidazolium salts's ability to bind to each target. Binding energy lower than zero remarks spontaneous binding, and equal and/or lower than -5 kcal/mol remarks good binding. Besides XO, the related compounds show higher activity against the AChE enzyme. They can also be analyzed as strong candidate compounds in biological studies of related enzymes. [ABSTRACT FROM AUTHOR]

The isostructural title compounds, {(C7H7N2)2[SnI4]}n, (1), and {(C7H5F2N2)2[SnI4]}n, (2), show a layered perovskite-type structure composed of anionic {[SnI4]2−}n sheets parallel to (100), which are decorated on both sides with templating benzimidazolium or 5,6-difluorobenzimidazolium cations, respectively. These planar organic heterocycles mainly form N—H...I hydrogen bonds to the terminal I atoms of the corner-sharing [SnI6] octahedra (point group symmetry 2) from the inorganic layer, but not to the bridging ones. This is in contrast to most of the reported structures of related compounds where ammonium cations are involved. Here hydrogen bonding to both types of iodine atoms and thereby a distortion of the inorganic layers to various extents is observed. For (1) and (2), all Sn—I—Sn angles are linear and no out-of-plane distortions of the inorganic layers occur, a fact of relevance in view of the material properties. The arrangement of the aromatic cations is mainly determined through the direction of the N—H...I hydrogen bonds. The coherence between organic bilayers along [100] is mainly achieved through van der Waals interactions.

Condensation of o-phenylenediamine with formic acid, acetic acid and glycolic acid gave a series of benzimidazole which on reaction with alkyl halide in phase transfer catalysis afforded the formation of the corresponding 1,3-dialkylbenzimidazolium salts. The structure has been established on the basis of spectroscopic and spectrometric analysis (1H and 13C NMR, IR, MS and single X-ray diffraction). The in vitro antibacterial activities of these salts have been investigated.

A new hydrated benzimidazolium salt containing spiro structure was obtained when benzimidazole is added to ethyl alcohol of 1,5-dioxaspiro[5.5]undecane-2,4-dione and trimethoxymethane. The title compound (C19H21O8) (C7H7N2) (0.5H2O) was characterized by elemental analysis, IR, UV-Vis, and single-crystal X-ray diffraction. The result shows that it belongs to the triclinic system, space group P-1, with a = 11.017(2) Å, b = 11.424(2) Å, c = 11.650(2) Å, α = 70.60(3)°, β = 71.00(3)°, α= 67.64(3)°, Mr = 505.51, V = 1245.2(5) Å, Z = 2, Dc = 1.348 g/cm³, F(000) = 534, μ(MoKa) = 0.102 mm-1. There exist two types of hydrogen bonds in the crystal. (C19H21O8)- anions and (C7H7N2)+ cations are linked by N-H⋯O hydrogen bonds, while (C19H21O8)- anions and free water are linked by O-H⋯O hydrogen bonds. All of the above hydrogen bonds form a one-dimensional (1D)-chained structure. The 1D chains further links the molecule into a three-dimensional (3D)-layered structure. [ABSTRACT FROM AUTHOR]

Imidazolium and benzimidazolium groups containing anion exchange membranes (AEMs) were synthesized by the functionalization of poly(styrene-co-vinylbenzyl chloride) with methylimidazole and methylbenzylimidazole, respectively. The essential properties for AEMs used in anion exchange membrane fuel cells (AEMFCs) including ion exchange capacity, water uptake, hydration number, and ionic conductivity were investigated. A comparative study of these two AEMs focusing on the alkaline stability was conducted in the present work. We have used TGA, FTIR, 1 H NMR, and 13 C NMR techniques to evaluate the susceptibility to alkaline degradation. Meanwhile, we have performed density functional theory (DFT) calculations to confirm the experimental results of the alkaline degradation study. It has been found that the benzimidazolium cations would be more easily attacked by OH − anions leading to ring-opening compared to the imidazolium cations. [ABSTRACT FROM AUTHOR]

N-heterocyclic carbenes (NHC) are now commonly encountered in organometallic and inorganic coordination chemistry because of its environmental friendly nature as solvent and catalyst, high activity, selectivity and easily recovered materials that were used to replace the traditional volatile organic solvents which generally suffered from environmental problems. Benzimidazole based ionic liquids (BILs) offering a new possibility for developing environmentally-friendly basic catalyst with transition metal and non-transition metal (Ag, Au, Ru, Rh, Fe, Co, Cu, Cd and Pd). They are flexible, nonvolatile, noncorrosive and immiscible with many organic solvents. In this review, we wish to present an overview of the preparation and applications in various reactions like alkylation, arylation, etherification, benzoin reaction, aldol condensation and metal mediated catalyst in Suzuki, Suzuki–Miyaura, Heck cross coupling and reduction, also in electrochemical application (electrocatalyst), anion sensor, solar cell, proton conduction, malaria parasite, antimicrobial activity, etc.

In the cation of the title molecular salt, C7H7N2+·C4H6NO4− (systematic name: 1H-benzo[d]imidazol-3-ium 2-azaniumylsuccinate), the benzimidazole ring system is almost planar (r.m.s. deviation = 0.012 Å). The cation is protonated at the N atom and the l-aspartate zwitterion is deprotonated at both carboxyl groups. In the anion, an N—H...O hydrogen bond and an N—H...O short contact generate S(6) graph-set motifs. In the crystal, the anions are linked via three N—H...O hydrogen bonds involving the NH3+ group, forming layers parallel to the ab plane. The benzimidazolium cations are linked to these layers by N—H...O hydrogen bonds. The layers are linked via C—H...O hydrogen bonds involving the benzimidazolium cation, forming a three-dimensional structure. There are also C—H...π interactions present involving inversion-related benzimidazolium cations.

In the anion of the title molecular salt, C7H7N2+·C7H5O3− (systematic name: 1H-benzimidazol-3-ium 2-hydroxybenzoate), there is an intramolecular O—H...O hydrogen bond that generates an S(6) ring motif. The CO2 group makes a dihedral angle of 5.33 (15)° with its attached ring. In the crystal, the dihedral angle between the benzimidazolium ring and the anion benzene ring is 75.88 (5)°. Two cations bridge two anions via two pairs of N—H...O hydrogen bonds, enclosing an R44(16) ring motif, forming a four-membered centrosymmetric arrangement. These units are linked via C—H...O hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked by C—H...π and π–π interactions [inter-centroid distances = 3.4156 (7) and 3.8196 (8) Å], forming a three-dimensional structure.

A series of novel chiral N-heterocyclic carbene rhodium complexes (NHC-Rh) based on benzimidazole have been prepared, and all of the NHC-Rh complexes were fully characterized by NMR and mass spectrometry. These complexes could be used as catalysts for the asymmetric 1,2-addition of organoboronic acids to aldehydes, affording chiral diarylmethanols with high yields and moderate enantioselectivities. [ABSTRACT FROM AUTHOR]

A series of C2-symmetric chiral benzimidazolium salts, the precursor of N-heterocyclic carbene ligands, were designed and synthesized from 1,2-dibromobenzene. In situ prepared corresponding carbenes were tested in the asymmetric palladium-catalyzed intramolecular -arylation of amides, affording chiral diarylmethanols with high yields and moderate enantioselectivities. [ABSTRACT FROM AUTHOR]

Vier Benzimidazoliumhydroxide mit einem C2 ‐ Phenylsubstituenten, der an seinen ortho ‐ Positionen Wasserstoff ‐ oder Bromatome sowie Methyl ‐ oder Phenylgruppen trägt, wurden hergestellt, und ihre Hydroxidstabilität wurde quantitativ analysiert. Die Unterschiede der Schutzgruppen hinsichtlich ihrer Stabilität in alkalischen Lösungen wurden mit Kristallstrukturen und Dichtefunktionalrechnungen erklärt. Die höchste Stabilität wurde für m ‐ Terphenyl ‐ geschütztes Benzimidazolium ermittelt, das eine Halbwertszeit von 3240 h in 3 m NaOD/CD3OD/D2O bei 80 °C aufwies. Ein Polymeranalog dieser Verbindung mit hohem Molekulargewicht wurde hergestellt, das exzellente mechanische Eigenschaften, eine hohe Ionenaustauschkapazität sowie eine bemerkenswerte Hydroxidstabilität in alkalischen Lösungen aufweist: Nach 168 h in 2 m KOH bei 80 °C wurde nur 5 % Zersetzung ermittelt. Dies ist das bis jetzt stabilste hydroxidleitende Benzimidazoliumpolymer. Es braucht Rückgrat: Durch eine neue Syntheseroute wurden Benzimidazoliumgruppen an einem sterisch abschirmenden Polyphenylen angebracht, um das bislang alkalistabilste Polybenzimidazolium zu erhalten. Die beobachtete Basenstabilität wird gestützt auf Kristallstrukturen und Dichtefunktionalrechnungen erklärt. [ABSTRACT FROM AUTHOR]

Four benzimidazolium hydroxide compounds, in which the C2-position is attached to a phenyl group possessing hydrogen, bromine, methyl groups, or phenyl groups at the ortho positions, are prepared and investigated for stability in a quantitative alkaline stability test. The differences between the stability of the various protecting groups in caustic solutions are rationalized on the basis of their crystal structures and DFT calculations. The highest stability was observed for the m-terphenyl-protected benzimidazolium, showing a half-life in 3 m NaOD/CD3OD/D2O at 80 °C of 3240 h. A high-molecular-weight polymer analogue of this model compound is prepared that exhibits excellent mechanical properties, high ionic conductivity and ion-exchange capacity, as well as remarkable hydroxide stability in alkaline solutions: only 5 % degradation after 168 h in 2 m KOH at 80 °C. This is the most stable hydroxide-conducting benzimidazolium polymer to date. [ABSTRACT FROM AUTHOR]

Paraoxonase (PON) is a key enzyme in metabolism of living organisms and decreased activity of PON1 was acknowledged as a risk for atherosclerosis and organophosphate toxicity. The present study describes the synthesis, characterization, PON1 inhibitory properties and molecular docking studies of functionalized imidazolium and benzimidazolium salts ( 1a – 5g ). The structures of all compounds were elucidated by IR, NMR, elemental analysis and structures of compounds 2b and 2c were characterized by single-crystal X-ray diffraction. Compound 1c , a coumarin substituted imidazolium salt showed the best inhibitory effect on the activity of PON1 with good IC 50 value (6.37 μM). Kinetic investigation was evaluated for this compound and results showed that this compound is competitive inhibitor of PON1 with K i value of 2.39 μM. Molecular docking studies were also performed for most active compound 1c and one of least active compound 2c in order to determine the probable binding model into active site of PON1 and validation of the experimental results. [ABSTRACT FROM AUTHOR]