نتایج جستجو برای: quaternization

تعداد نتایج: 182  

2015
Marcel Mirel Popa Emilian Georgescu Mino R Caira Florentina Georgescu Constantin Draghici Raluca Stan Calin Deleanu Florea Dumitrascu

The three possible structural isomers of 4-(pyridyl)pyrimidine were employed for the synthesis of new pyrrolo[1,2-c]pyrimidines and new indolizines, by 1,3-dipolar cycloaddition reaction of their corresponding N-ylides generated in situ from their corresponding cycloimmonium bromides. In the case of 4-(3-pyridyl)pyrimidine and 4-(4-pyridyl)pyrimidine the quaternization reactions occur as expect...

2013
Christian Dollendorf Martin Hetzer Helmut Ritter

A redox-responsive polycationic system was synthesized via copolymerization of N,N-diethylacrylamide (DEAAm) and 2-(dimethylamino)ethyl methacrylate (DMAEMA). N,N'-bis(4-chlorobutanoyl)cystamine was used as disulfide-containing cross-linker to form networks by the quaternization of tertiary amine groups. The insoluble cationic hydrogels become soluble by reduction of disulfide to mercaptanes by...

2017
Xinjuan Li Kai Wang Nana Ma Xianbin Jia

Naked-eye detection of amino acids (AA) in water is of great significance in the field of bioanalytical applications. Herein, polymerized ionic liquids (PILs) with controlled chain length structures were synthesized via reversible addition-fragmentation chain-transfer (RAFT) polymerization and post-quaternization approach. The AA recognition performance of PILs with different alkyl chain length...

Journal: :Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 2008
Wen-Chu Yang Fred E Regnier Dan Sliva Jiri Adamec

A fast and sensitive LC-ESI-MS method is described for the comparative quantification of 16 estrogen metabolites based on the derivatization of estrogens with a novel derivatizing reagent, N-methyl-nicotinic acid N-hydroxysuccinimide ester (C1-NA-NHS). The process introduces a quaternary amine to the analytes, making the analytes permanently charged regardless of the pH of the high-performance ...

2015
Pengtao Liu Weisheng Meng Shuai Wang Yonghui Sun Muhammad Aqeel Ashraf

A series of 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) was prepared by the reaction of chitosan with glycidyl trimethyl ammonium chloride. Structure of HACC was characterized by FT IR and 1H NMR spectroscopies, and it was proved that substitution reaction mainly occurs on the N element. Antimicrobial activities of HACC was examined against S. aureus, E. coli, and A. niger. Resul...

Journal: :Academic journal of computing & information science 2023

Materials of 3D structure for HPLC columns have been prepared. Silica spheres with high purity were first funetionalized Substance A and a range other substances, finally followed by quaternization iodomethane to form the final product. standard solution four certain phthalates was used verify chromatographic performance resulting packing materia1. Quantification analysis performed external met...

2015
Ben W. Boal Stacey I. Zones Mark E. Davis

The synthesis of aluminophosphates is investigated using a number of triptycene-based organic structure-directing agents (OSDA). These OSDAs are designed to synthesize extra-large pore and/or large cavity-containing molecular sieves. Starting from the hydrophobic triptycene molecule, OSDAs are prepared by introducing three amine-based centers that can be charged either by protonation in the aci...

2018
Benedikt C Melzer Jan G Felber Franz Bracher

Highly-substituted isoquinolines are important scaffolds in syntheses of natural products and in drug development and hence, effective synthetic approaches are required. Here we present a novel method for the introduction of a methyl group at C1 of isoquinolines. This is exemplified by a new total synthesis of the alkaloid 7-hydroxy-6-methoxy-1-methylisoquinoline. Direct metalation of 7-benzylo...

Journal: :Journal of the American Chemical Society 2008
Paulson Mathew Antonia Neels Martin Albrecht

The [3 + 2] cycloaddition of azides and acetylenes followed by nitrogen quaternization was applied for the generation of novel and highly modular triazolium salts. The selective substitution of the 1,3,4-substitution pattern presets such salts as precursors for a new class of abnormal carbene ligands, thus expanding the family of these high-impact ligands. Metalation of the triazolium salts is ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید