Quaternary
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Quaternary ammonium salts (QUATs) are compounds with wide use in organic synthesis, pharmacy or other fields of industry. Thanks to their specific physical and chemical properties resulting from their amphiphilic character they are already used as phase-transfer catalysts, ionic liquids, dyes, antimicrobial agents and disinfectants, antiarrhythmics, bronchodilators etc. There is still an effort to prepare new active compounds. Several organosynthetic methods are used to prepare QUATs: probably the best way is the Menshutkin reaction. Recently, also a microwave synthesis was introduced to prepare QUATs bringing better yields, shorter reaction times and a possibility of solvent-free reactions.
Quaternary ammonium compounds, referred to as QACs, are cationic substances with a structure on the edge of organic and inorganic chemistry and unique physicochemical properties. The purpose of the present work is to introduce QACs and their wide application potential. Fundamental properties, methods of preparation, and utilization in organic synthesis are reviewed. Modern applications and the use of QACs as reactive substrates, reagents, phase-transfer catalysts, ionic liquids, electrolytes, frameworks, surfactants, herbicides, and antimicrobials are further covered. A brief discussion of the health and environmental impact of QACs is also provided. The emphasis is largely on tetraalkylammonium compounds bearing linear alkyl chains.
- MeSH
- antiinfekční látky chemická syntéza chemie farmakologie MeSH
- herbicidy chemická syntéza chemie farmakologie MeSH
- kvartérní amoniové sloučeniny chemická syntéza chemie farmakologie MeSH
- povrchově aktivní látky chemická syntéza chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Journal of chemotherapy, ISSN 1120-009X Volume 8, Suppl. n. 2, February, 1996
114 stran : ilustrace, tabulky ; 27 cm
- MeSH
- antibakteriální látky terapeutické užití MeSH
- bakteriální infekce farmakoterapie MeSH
- cefalosporiny terapeutické užití MeSH
- Publikační typ
- sborníky MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- farmakoterapie
- infekční lékařství
- NLK Publikační typ
- brožury
- MeSH
- alkaloidy farmakologie MeSH
- antiinfekční látky farmakologie MeSH
- apoptóza účinky záření MeSH
- biotransformace MeSH
- fenantridiny farmakologie MeSH
- finanční podpora výzkumu jako téma MeSH
- isochinoliny farmakologie chemie toxicita MeSH
- kometový test MeSH
- poškození DNA MeSH
- techniky in vitro MeSH
- vztahy mezi strukturou a aktivitou MeSH
Purpose: Plasmonic photothermal cancer therapy by gold nanorods (GNRs) emerges as a promising tool for cancer treatment. The goal of this study was to design cationic oligoethylene glycol (OEG) compounds varying in hydrophobicity and molecular electrostatic potential as ligand shells of GNRs. Three series of ligands with different length of OEG chain (ethylene glycol units = 3, 4, 5) and variants of quaternary ammonium salts (QAS) as terminal functional group were synthesized and compared to a prototypical quaternary ammonium ligand with alkyl chain - (16-mercaptohexadecyl)trimethylammonium bromide (MTAB). Methods: Step-by-step research approach starting with the preparation of compounds characterized by NMR and HRMS spectra, GNRs ligand exchange evaluation through characterization of cytotoxicity and GNRs cellular uptake was used. A method quantifying the reshaping of GNRs was applied to determine the effect of ligand structure on the heat transport from GNRs under fs-laser irradiation. Results: Fourteen out of 18 synthesized OEG compounds successfully stabilized GNRs in the water. The colloidal stability of prepared GNRs in the cell culture medium decreased with the number of OEG units. In contrast, the cellular uptake of OEG+GNRs by HeLa cells increased with the length of OEG chain while the structure of the QAS group showed a minor role. Compared to MTAB, more hydrophilic OEG compounds exhibited nearly two order of magnitude lower cytotoxicity in free state and provided efficient cellular uptake of GNRs close to the level of MTAB. Regarding photothermal properties, OEG compounds evoked the photothermal reshaping of GNRs at lower peak fluence (14.8 mJ/cm2) of femtosecond laser irradiation than the alkanethiol MTAB. Conclusion: OEG+GNRs appear to be optimal for clinical applications with systemic administration of NPs not-requiring irradiation at high laser intensity such as drug delivery and photothermal therapy inducing apoptosis.
- MeSH
- biologický transport MeSH
- HeLa buňky MeSH
- hydrofobní a hydrofilní interakce MeSH
- koloidy MeSH
- kvartérní amoniové sloučeniny chemie MeSH
- lidé MeSH
- ligandy MeSH
- nanotrubičky chemie MeSH
- polyethylenglykoly chemie MeSH
- stabilita léku MeSH
- teplota * MeSH
- zlato chemie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Tertiary amines 3-(dialkylamino)-2-hydroxypropyl 4-[(alkoxycarbonyl)amino]benzoates and their quaternary ammonium salts were synthesized. The final step of synthesis of quaternary ammonium salts was carried out by microwave-assisted synthesis. Software-calculated data provided the background needed to compare fifteen new resulting compounds by their physicochemical properties. The acid dissociation constant (pKa) and lipophilicity index (log P) of tertiary amines were determined; while quaternary ammonium salts were characterized by software-calculated lipophilicity index and surface tension. Biological evaluation aimed at testing acetylcholinesterase and butyrylcholinesterase-inhibiting activity of synthesized compounds. A possible mechanism of action of these compounds was determined by molecular modelling study using combined techniques of docking; molecular dynamics simulations and quantum mechanics calculations.
- MeSH
- acetylcholinesterasa MeSH
- aktivace enzymů účinky léků MeSH
- benzoáty chemická syntéza chemie farmakologie MeSH
- butyrylcholinesterasa MeSH
- chemické modely MeSH
- cholinesterasové inhibitory chemická syntéza chemie farmakologie MeSH
- kvartérní amoniové sloučeniny chemická syntéza chemie farmakologie MeSH
- molekulární modely * MeSH
- soli chemie MeSH
- techniky syntetické chemie * MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH
