A simple and efficient procedure for the synthesis of new optically active imidazolium and triazolium ionic liquids in a three step reaction sequence is described. In the first step, the ring opening of 1,2‐butylene oxide by imidazole or 1,2,4‐triazole resulted in the formation of N‐2‐hydroxybutylimidazole and N‐2‐hydroxybutyl‐1,2,4‐triazole, respectively. In the second step, racemic mixtures of the secondary alcohols were resolved with good enantioselectivity by a lipase‐catalyzed transesterification with enol esters (vinyl acetate and 1‐acetoxy‐2‐methylcyclohexene). In the final step, the optically active intermediates were alkylated with several haloalkanes to yield optically active ionic liquids. The inhibitory activity of the synthesized ionic liquids was tested towards gram‐negative and gram‐positive bacteria and fungi.
SummaryRacemic 1-(β-hydroxypropyl)azoles were prepared by solvent-free direct regioselective ring opening of 1,2-propylene oxide with imidazole or 1,2,4-triazole. Lipase-catalyzed transesterification of alcohols with vinyl acetate resulted in kinetic enantiomers resolution. Separated (S)-enantiomers of (+)-1-(1H-imidazol-1-yl)propan-2-ol and (+)-1-(1H-1,2,4-triazol-1-yl)propan-2-ol were quaternized with alkyl bromides or iodides, yielding novel optically active ionic liquids. Racemic salts were tested against a wide range of microorganisms.
Atomic force microscopy (AFM) and fluorescence microscopy was applied to determine the influence of the anti-aging peptides on the morphology and the mechanical properties of keratinocytes. Immortalized human keratinocytes (HaCaT) were treated with two anti-aging bioactive peptides: Acetyl Tetrapeptide-2 and Acetyl Hexapeptide-50 (Lipotec). The AFM measurement of the keratinocyte stiffness were carried after 48 h exposure at an indentation depth of 200 nm. AFM analysis showed increase of the cell stiffness for cells treated with Acetyl Tetrapeptide-2 (P1) in concentration range. Acetyl Hexapeptide-50 (P2) at concentration of 0.05 µg/ml also increased the stiffness of HaCaT cells but at higher concentrations 0.5 and 5 µg/ml cell stiffness was lower as compared to untreated control. Fluorescence microscopy revealed remodeling of actin filaments dependent on the concentration of P2 peptide. The mechanical response of HaCaT cells treated with P2 peptide corresponds to change of transcription level of ACTN1 and SOD2 which activity was expected to be modulated by P2 treatment.
This work was focused on biodegradation with Escherichia coli bacteria studies of PSF-PUR blend semipermeable hollow fiber membranes that possibly can undergo a partial degradation process. Hollow fiber membranes were obtained from polysulfone (PSF) and polyurethane (PUR) containing ester bonds in the polymer chain in various weight ratios using two solvents: N,N-Dimethylmethanamide (DMF) or N-Methylpyrrolidone (NMP). The membranes that underwent the biodegradation process were tested for changes in the ultrafiltration coefficient (UFC), retention and cut-off point. Moreover, the membranes were subjected to scanning electron microscopy (SEM), MeMoExplorerTM Software and Fourier-transform infrared spectroscopy (FT-IR) analysis. The influence of E. coli and its metabolites has been proven by the increase in UFC after biodegradation and changes in the selectivity and porosity of individual membranes after the biodegradation process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.