betadex and imidazole

Achieving rapid and highly sensitive small molecule chiral discrimination is a great challenge in modern-day analytical sciences. Herein, an organic field effect transistors (OFET) is developed by employing an imidazolium 3,5-dimethylphenylcabamoylated-β-cyclodextrin (Im

Topics: beta-Cyclodextrins; Cations; Electrons; Imidazoles; Macromolecular Substances; Small Molecule Libraries; Transistors, Electronic

Clotrimazole (CTZ) and cyclodextrin (CD) inclusion complexes having improved apparent water solubility were obtained from phase solubility diagrams. β-CD (1.5% w/w) and hydroxypropyl-β-CD (40% w/w) offered poor CTZ solubility enhancements (12 and 384 times, respectively). Unexpectedly, the apparent solubility of CTZ was 9980 times increased from 0.4 µg.mL(-1) (1.42 μM) without CD to 4.89 mg.mL(-1) (14.9 mM) using randomly-methylated β-CD (Me-β-CD) (40% w/w). This is the highest apparent CTZ solubility improvement ever reported in the literature using conventional CDs. Quantitative nuclear magnetic resonance ((1) H-NMR) coupled with two-dimensional nuclear Overhauser effect (NOESY) experiments and molecular docking calculations showed that the highest interactions with Me-β-CD were reported for CTZ two phenyl groups. A lower interaction was reported for chlorophenyl, while imidazole had the weakest interaction with Me-β-CD.

Topics: Antifungal Agents; beta-Cyclodextrins; Chemistry, Pharmaceutical; Clotrimazole; Imidazoles; Methylation; Models, Molecular; Molecular Docking Simulation; Proton Magnetic Resonance Spectroscopy; Solubility

Switchable DNA condensers based on β-cyclodextrin derivates bearing cationic imidazolium moieties and hydrolysable ester linkages were synthesized, showing base-responsive or enzyme-responsive switchable DNA condensation ability under physiological conditions.

Topics: beta-Cyclodextrins; Cations; Cell Survival; DNA; Glycolipids; HEK293 Cells; HeLa Cells; Humans; Imidazoles; Microscopy, Atomic Force; Plasmids

Some functionalized 1,2,4,5-tetrasubstituted imidazole derivatives were synthesized using a one-pot, four component reaction involving 1,2-diketones, aryl aldehydes, ammonium acetate and substituted aromatic amines. The synthesis has been efficiently carried out in a solvent free medium using β-cyclodextrin-propyl sulfonic acid as a catalyst to afford the target compounds in excellent yields. The local anesthetic effect of these derivatives was assessed in comparison to lidocaine as a standard using a rabbit corneal and mouse tail anesthesia model. The three most potent promising compounds were subjected to a rat sciatic nerve block assay where they showed considerable local anesthetic activity, along with minimal toxicity. Among the tested analogues, 4-(1-benzyl-4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (5g) was identified as most potent analogue with minimal toxicity. It was further characterized by a more favourable therapeutic index than the standard.

Topics: Anesthetics, Local; Animals; beta-Cyclodextrins; Catalysis; Cornea; Imidazoles; Inhibitory Concentration 50; Lidocaine; Male; Mice; Rabbits; Sulfonic Acids

The first member of the single-isomer, dicationic cyclodextrin (CD) family, 6(A)-ammonium-6(C)-butylimidazolium-β-cyclodextrin chlorides (AMBIMCD), has been synthesized, analytically characterized, and used to separate a variety of acidic enantiomers and amino acids by CE. Starting from mono-6(A)-azido-β-cyclodextrin, the cationic imidazolium and ammonium moieties were subsequently introduced onto primary ring of β-cyclodextrin via nucleophilic addition and Staudinger reaction. The analytically pure AC regio-isomer CD was further obtained via column chromatography. This dicationic CD exhibited excellent enantioselectivities for selected analytes at concentration as low as 0.5 mM, which were even better than those of its mono-imidazolium or ammonium-substitued counterpart CDs at 10 equivalent concentrations. The effective mobilities of all studied analytes were found to decrease with the concentration of AMBIMCD. Inclusion complexation in combination with eletrostatic interactions seemed to account for the enhanced chiral discrimination process.

Topics: Amino Acids; beta-Cyclodextrins; Cations; Chlorides; Electrophoresis, Capillary; Hydrogen-Ion Concentration; Imidazoles; Isomerism; Quaternary Ammonium Compounds; Stereoisomerism

Per-6-amino-beta-cyclodextrin (per-6-ABCD), acting simultaneously as a supramolecular ligand for CuI and host for aryl bromides, catalyzes N-arylation of imidazole with aryl bromides under mild conditions. This simple method proceeds with excellent yield for the coupling of imidazole with various substituted aryl bromides demonstrating good tolerance of other functionalities.

Topics: beta-Cyclodextrins; Bromine; Catalysis; Copper; Imidazoles; Ligands; Nitrogen

The high-performance liquid chromatography retention mechanism of a series of six imidazole derivatives was investigated over a wide range of mobile-phase compositions, pH, and column temperatures using a beta-cyclodextrin (beta-CD)-bonded chiral stationary phase. Thermodynamic constants for the transfer of a solute from the mobile to the beta-CD stationary phase were determined. Different van't Hoff plot shapes were observed with mobile-phase pH values, indicating a change in the retention mechanism. Enthalpy-entropy compensation revealed that the solute retention mechanism was independent of the compound molecular structure, the same at pH 7 and 7.5, but changed at pH 6.5, 8, and 8.5. Differential scanning calorimetry and thermogravimetric analysis were used to show different thermal features for the beta-CD stationary phase at pH 6.5, 8, and 8.5 and at pH 7 and 7.5. A new theory was presented to explain the beta-CD cavity structure balance between an ordered and disordered state. Variations of column temperature and mobile-phase pH tend to cause this phase transition between these two states, explaining the thermodynamic constant variations with pH and temperature.

Topics: beta-Cyclodextrins; Chromatography, High Pressure Liquid; Cyclodextrins; Differential Thermal Analysis; Imidazoles; Mathematics; Solubility