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[Display omitted] • The bicyclic α-iminophosphonates showed high synthetic possibilities. • Imidazoline I 2 receptors are promising therapeutic targets in neurodegeneration. • (Octahydropyrrolo[3,4- c ]pyrrol-1-yl)phosphonates show affinity/selectivity for imidazoline I 2 receptors. • This is the first time, we showed cognitive improvement in C. elegans after I 2 -IR ligands treatment. Recent studies pointed out the modulation of imidazoline I 2 receptors (I 2 -IR) by selective ligands as a putative strategy to face neurodegenerative diseases. Foregoing the classical 2-imidazoline/imidazole-containing I 2 -IR ligands, we report a family of bicyclic α-iminophosphonates endowed with high affinity and selectivity upon I 2 -IR and we advanced a representative compound B06 in preclinical phases. In this paper, we describe the synthetic possibilities of bicyclic α-iminophosphonates by exploring its ambivalent reactivity, leading to unprecedented molecules that showed promising activities as I 2 -IR ligands in human brain tissues and good BBB permeation capabilities. After in silico ADME prediction studies, we assessed the neuroprotective properties of selected compounds and beneficial effect in an in vitro model of Alzheimeŕs and Parkinson's disease. Along with their neuroprotective effect, compounds showed a potent anti-inflammatory response when evaluated in a neuroinflammation cellular model. Moreover, this is the first time that the neuroprotective effects of imidazoline I 2 -IR ligands in a transgenic Alzheimer's disease Caenorhabditis elegans strain are investigated. Using a thrashing assay, we found a significant cognition improvement in this in vivo model after treatment with the new bicyclic α-phosphoprolines. Therefore, our results confirmed the need of exploring structurally new I 2 -IR ligands and their potential for therapeutic strategies in neurodegeneration. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Small organic molecules were found to be effective inhibitors of BACE-1 enzyme. • Tetrahydrobenzo[ b ]pyrans were targeted for the BACE-1 enzyme in docking studies. • Those compounds were synthesized in the lab and characterized using spectral data. • The synthesized compounds were subjected for in-vitro studies against the enzyme. • One compound with code KVB-5 (4e) was showing IC50 value at nanomolar concentration. Abstract β -Secretase (BACE1) has been broadly documented as one of the possible therapeutic targets for the treatment of Alzheimer's disease. In this paper, we report the synthesis and the for β -secretase (BACE-1) inhibitory activity of new series of tetrahydrobenzo [ b ] pyran derivatives. One-pot synthesis of tetrahydrobenzo [ b ] pyrans was carried out by condensing aromatic aldehyde, malononitrile and 1,3-cyclohexanedione using ionic liquid 1-butyl-3-methyl imidazolium chloride ([bmIm]Cl−) in aqueous alcohol media. The addition of alcohol and water in the ratio of 1:2 keeps all the reactants in solution which facilitates the reaction and makes the product formation very easy. The synthesized compounds were subjected to BACE1 inhibition assay and six compounds, 4d, 4e, 4f, 4h, 4i, and 4p have shown significant IC 50 values at micromolar level. Among these six active compounds, 4e was a potential inhibitor with its IC 50 value in nanomolar range. All the synthesized compounds were docked onto the active site of β -Secretase enzyme. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract In this paper, we aimed to develop a reversible and effective method to control the surface activity and self-assembled morphology of amphiphilic imidazolium-type ionic liquids (G) in water. For this purpose, a series of pillar[5]arene/imidazolium supramolecular complexes were designed and prepared. Before the formation of the host-guest complex, the surface activity of G7 worked well, and foams could be generated easily. However, after the addition of water-soluble pillar[5]arene (WP5), the rigid WP5 platform caused steric hindrance that prevented the hydrophobic chains on G7 from getting close to each other, inducing the change in surface activity. On the other hand, because paraquat (PQ) has a larger association constant with WP5 than G7 , the surface activity of the solution can be recovered after the addition of PQ. TEM confirmed that self-assembled morphologies of this reversible system transformed from nanoparticles to nanosheets then to nanoparticles. It is anticipated that this supramolecular method for controlling the surface activity of amphiphiles in a reversible way may find application in fields where fast foaming and defoaming are needed. [ABSTRACT FROM AUTHOR]

This paper presents novel data on density, viscosity and refractive index of four binary mixtures constituted of ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate and N-methyl-2-pyrrolidone/or 1-hexanol/or liquid polyethylene glycols with molar mass 200/or 400, in the temperature range from T  = 288.15 K to 333.15 K and at pressure of p  = .1 MPa. Thermal conductivity has been measured for mixtures of ionic liquid and polyethylene glycol 200/or polyethylene glycol 400 in the temperature range from T  = 303.15 to 323.15 K and at a pressure of p  = .1 MPa. All these solutions have the potential for application in regenerative flue gas desulfurization processes. From experimental values of densities, viscosities, thermal conductivities and refractive indices, excess molar volumes and deviations in viscosity, thermal conductivity and refractive index have been calculated and correlated with Redlich-Kister polynomial equation. The values of excess and deviation functions were used for analysis of molecular interactions present in the investigated solutions. In addition, modeling of transport properties, viscosity and thermal conductivity, was carried out and the obtained results were interpreted taking into account the applied approaches and models. [ABSTRACT FROM AUTHOR]

In this paper, two novel zeolitic imidazole framework (ZIF) materials, ZIF-9 and ZIF-12 were firstly introduced as catalysts to activate PMS for Rhodamine B degradation. ZIF-9 and ZIF-12 have the same composition in metal ions (Co 2+ ) and organic linker, but show different structural topologies (SOD and RHO, respectively) and particle size. The two ZIFs were successfully synthesized and characterized via SEM and PXRD. Both ZIF-9 and ZIF-12 as the PMS activation catalysts were evaluated and compared, and the underlying mechanism was proposed. The nanoscale nature enables ZIF-9 a closer contact with PMS, which leading to degradation rate ZIF-9 > ZIF-12 at the time of 5 min (54.8% and 27.7%, respectively). And the degradation of ZIF-12 gradually caught up with ZIF-9 when the reaction time was longer, which can be attributed to the RHO topology and larger cage size of ZIF-12. The efficient degradation of RhB indicates that ZIF-9 and ZIF-12 can be promising heterogeneous catalyst to activate PMS for the degradation of RhB. [ABSTRACT FROM AUTHOR]

Ternary liquid-liquid equilibria were experimentally determined for eight systems composed of an ionic liquid + n -hexane + an organic compound implicated in the racemic resolution of rac -2-pentanol ( rac -2-pentanol, vinyl butyrate, rac -2-pentyl butyrate or butyric acid) at a temperature of 303.15 K and pressure of 0.1 MPa. The following ionic liquids were used: 1-ethyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide, [emim + ][NTf 2 − ], and 1-hexyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide, [hmim + ][NTf 2 − ]. The binodal curves and the tie line of the conjugate phases compositions were determined through measurement of the refractive index for the ionic liquid-rich phase and by using gas chromatography for the hexane-rich phase, enabling their potential to be assessed for selective extraction of organic compounds from a mixture of ionic liquid reaction media for the resolution of rac -2-pentanol. Liquid phase activity coefficients were calculated using the Non-Random Two-Liquid equation and the tie line theoretical data calculated from the model are in good agreement with the experimental data. As yet, the literature contains no data for the systems studied in this paper. [ABSTRACT FROM AUTHOR]

A well-considered treatment of acute nerve agents poisoning involves the exogenous administration of butyrylcholinesterase (BChE, EC 3.1.1.8) as a stoichiometric bioscavenger efficient in preventing cholinergic crises caused by acetylcholinesterase (AChE, EC 3.1.1.7) inhibition. An additional improvement in medical countermeasures would be to use oximes that could reactivate BChE as well to upgrade bioscavenging from stoichiometric to oxime-assisted catalytic. Therefore, in this paper we investigated the potency of 39 imidazolium and benzimidazolium oximes (36 compounds synthesized for the first time) to be considered as the reactivators specifically designed for reactivation of phosphylated human BChE. Their efficiency in the reactivation of paraoxon-, VX-, and tabun-inhibited human BChE, as well as human AChE was tested and compared with the efficiencies of HI-6 and obidoxime, used in medical practice today. A comprehensive analysis was performed for the most promising oximes defining kinetic parameters of reactivation as well as interactions with uninhibited BChE. Furthermore, experimental data were compared with computational studies (docking, QSAR analysis) as a starting point in future oxime structure refinement. Considering the strict criteria set for in vivo applications, we determined the cytotoxicity of lead oximes on two cell lines. Among the tested oxime library, one imidazolium compound was selected for preliminary in vivo antidotal study in mice. The obtained protection in VX poisoning outlines its potential in development oxime-assisted OP-bioscavenging with BChE. [ABSTRACT FROM AUTHOR]

This paper reports experimental values of dynamic viscosity for four binary systems of 1-ethyl-3-methylimidazolium tetrafluoroborate, [Emim][BF4], with dimethyl sulfoxide (DMSO), acetonitrile (ACN), ethylene glycol (EG) and 1,4-dioxane over the temperature ranges from 293.15 K to 353.15 K at p = 0.1 MPa. All binary mixtures were completely miscible over the entire range of mole fraction, except the system with 1,4-dioxane. The viscosity results have been correlated by the one parameter Grunberg–Nissan and Fang and He equations and the two-parameter McAllister, Eyring-UNIQUAC, Eyring-NRTL and Eyring-Wilson models and the results were compared. Additionally, the viscosity deviations, Δ η , and the excess Gibbs energy of activation for viscous flow, G ∗ E , were calculated and fitted to the Redlich–Kister equation. The results show that all Δ η values are negative over the whole composition range and the G ∗ E values are positive, except for the system with EG. The results of the excess functions are discussed in terms of molecular interactions. [ABSTRACT FROM AUTHOR]

The acquisition of proton conductive hydrogen-bonded organic frameworks (HOFs) and metal-organic frameworks (MOFs) has recently received sustained attention. In this paper, 2-(p -N-imidazole)phenyl-1H-4,5-imidazole dicarboxylic acid (p -IPhH 3 IDC) was employed to solvothermally synthesize a 3D HOF, [ p -IPhH 3 IDC]·2H 2 O (1), and a 3D Ni(II) MOF, {[Ni(p -IPhH 2 IDC) 2 ]·H 2 O} n (2). Their crystal structures have been characterized by single-crystal X-ray diffraction. By means of thermogravimetric analysis, X-ray powder diffraction, and scanning electron microscopy determinations, it was confirmed that both compounds have excellent thermal and water stability. Subsequently, their proton conductive properties were tested by AC determinations. It was found that their proton conductivities increased with the rising humidity and temperature. At 100 ​°C and 98% RH, the optimal proton conductivities are 1.06 ​× ​10−5 ​S ​cm−1 for 1 and 3.97 ​× ​10−5 ​S·cm−1for 2. Finally, the proton-conducting mechanisms of the two compounds were deduced. This work offers new inspiration for the exploration of novel proton-conductive materials. [Display omitted] •Two highly stable HOF and MOF from an imidazole dicarboxylate compound were synthesized. •Their proton conductivity were investigated at variable RHs and temperatures. •The proton-conducting mechanism was deduced [ABSTRACT FROM AUTHOR]

This paper reports an experimental and theoretical study on the structural and energetic characterization of the 2-mercaptoimidazole (2-MI) in the solid and in the gaseous phases. The single crystal X-ray diffraction determinations on the anhydrous and hemihydrate 2-MI forms were carried out at T = (296 ± 2) K and T = (150 ± 2) K, respectively, and suggest that in both forms the 2-MI molecule is closer to the thione conformation, albeit some single bond character is possible. The energy of combustion of the title compound was measured by rotating-bomb combustion calorimetry, being used to derive the corresponding enthalpy of formation in the crystalline-phase. The enthalpy of sublimation of 2-MI, at T = 298.15 K, was obtained from high temperature Calvet microcalorimetry measurements. These two parameters yielded the gas-phase enthalpy of formation, allowing the inherent energetic analysis of the molecule. This result was discussed together with the corresponding predictions for 2-MI and its tautomer, 1,3-dihydro-2 H -imidazole-2-thione, by the G3 method. The dehydration reaction of 2-MI · 0.5H 2 O(cr) was also investigated and the corresponding enthalpy of dehydration was determined by Calvet microcalorimetry. [ABSTRACT FROM AUTHOR]

This paper assesses the biocompatibility for fluorescence imaging of colloidal nanocrystal quantum dots (QDs) coated with a recently-developed multiply-binding methacrylate-based polymeric imidazole ligand. The QD samples were purified prior to ligand exchange via a highly repeatable gel permeation chromatography (GPC) method. A multi-well plate based protocol was used to characterize nonspecific binding and toxicity of the QDs toward human endothelial cells. Nonspecific binding in 1% fetal bovine serum was negligible compared to anionically-stabilized QD controls, and no significant toxicity was detected on 24 h exposure. The nonspecific binding results were confirmed by fluorescence microscopy. This study is the first evaluation of biocompatibility in QDs initially purified by GPC and represents a scalable approach to comparison among nanocrystal-based bioimaging scaffolds. [ABSTRACT FROM AUTHOR]

In this paper, a densimeter based on vibrating tube principle is used to determine experimentally the density of 1-butyl-2,3-dimethylimidazolium tris(pentafluoroethyl)trifluorophosphate and 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide at temperatures between (278.15 and 398.15) K and at pressures up to 120 MPa. The apparatus was calibrated by using water, vacuum and bromobenzene. The Tammann–Tait equation of state was used to correlate ( p , T , ρ ) results with standard deviations around 2 · 10 −4 g · cm −3 . Other volumetric properties, such as isothermal compressibility and isobaric thermal expansivity, were obtained from this equation. For each ionic liquid, the α p isotherms present a crossing point within the experimental pressure range. Besides, the effect that the C2-methylation in the imidazolium cation provokes on density values is analyzed. The prediction ability of the group contribution methods of Gardas and Coutinho and Jacquemin et al. were tested with the experimental densities. [ABSTRACT FROM AUTHOR]

Various chemicals in the environment always exist as mixtures. Toxicity interaction within mixtures may pose potential hazards and risks to the environmental safety and human health. Recent studies showed that toxicity interaction by ionic liquid (IL) mixtures can be related to a certain component. To identify the component, we developed a novel procedure integrating an up-to-down process with the uniform design-based ray method (UDUD) and applied it into an IL mixture system of four 1-butyl-3-methylimidazolium ILs (simply [bmim]X) where X=Cl−, Br−, CH3OSO3− and CH3(CH2)7OSO3−. It was shown that two mixture rays in the quaternary system exhibited significant antagonistic interaction. In this paper, the UDUD was first employed to design four ternary mixture systems. The microplate toxicity analysis was used to determine the toxicities of various mixtures to a freshwater photobacterium Vibrio qinghaiensis sp.-Q67. The concentration addition was taken as an additive reference to assess the toxicity interactions taking place in mixtures. The results revealed that some ternary mixture rays including [bmim]CH3(CH2)7OSO3 display antagonism while the ternary rays without [bmim]CH3(CH2)7OSO3 exhibit additivity. On these grounds, we again designed all binary mixtures containing [bmim]CH3(CH2)7OSO3, determined their toxicities and assessed toxicity interaction. The results showed that three binary mixture systems produce antagonism. Thus, it may be concluded that [bmim]CH3(CH2)7OSO3 is indeed a key component inducing mixture antagonism. [ABSTRACT FROM AUTHOR]