Search results for "CLICK CHEMISTRY"
showing 10 items of 106 documents
Copper(I)‐chitin biopolymer based: An efficient and recyclable catalyst for click azide–alkyne cycloaddition reactions in water
2021
Clicked and long spaced galactosyl- and lactosylcalix[4]arenes: New multivalent galectin-3 ligands
2014
Four novel calix[4]arene-based glycoclusters were synthesized by conjugating the saccharide units to the macrocyclic scaffold using the CuAAC reaction and using long and hydrophilic ethylene glycol spacers. Initially, two galactosylcalix[4]arenes were prepared starting from saccharide units and calixarene cores which differ in the relative dispositions of the alkyne and azido groups. Once the most convenient synthetic pathway was selected, two further lactosylcalix[4]arenes were obtained, one in the cone, the other one in the 1,3-alternate structure. Preliminary studies of the interactions of these novel glycocalixarenes with galectin-3 were carried out by using a lectin-functionalized chip…
A nitric oxide induced “click” reaction to trigger the aggregation induced emission (AIE) phenomena of a tetraphenyl ethylene derivative: A new fluor…
2020
Abstract An Aggregation Induced Emission (AIE) transduction mechanism has been used to detect nitric oxide (NO). A new tetraphenylethylene derivative functionalized with alkyne moieties has been prepared to work as a fluorescent probe. A “click” reaction was chosen because NO is able to generate the required catalytic species by reducing Cu(II) to Cu(I).
Cu(ii)-alginate-based superporous hydrogel catalyst for click chemistry azide-alkyne cycloaddition type reactions in water.
2020
A novel sustainable hydrogel catalyst based on the reaction of sodium alginate naturally extracted from brown algae Laminaria digitata residue with copper(II) was prepared as spherical beads, namely Cu(II)-alginate hydrogel (Cu(II)-AHG). The morphology and structural characteristics of these beads were elucidated by different techniques such as SEM, EDX, BET, FTIR and TGA analysis. Cu(II)-AHG and its dried form, namely Cu(II)-alginate (Cu(II)-AD), are relatively uniform with an average pore ranging from 200 nm to more than 20 μm. These superporous structure beads were employed for the copper catalyzed [3 + 2] cycloaddition reaction of aryl azides and terminal aryl alkynes (CuAAC) via click …
A Polar18F-Labeled Amino Acid Derivative for Click Labeling of Biomolecules
2014
This work describes the synthesis and 18F-labeling of an amino acid based prosthetic group that is able to participate in copper(I)-catalyzed cycloadditions. The prosthetic group can be used for 18F labeling of biomolecules under mild conditions. The synthesis started with L-serine methyl ester, which was derivatized by introducing an alkyne moiety and a leaving group for 18F labeling. Subsequently, 18F labeling as well as deprotection conditions were screened, which resulted in an overall radiochemical yield (RCY) of around 28 %. Furthermore, the 18F-labeled prosthetic group was treated with an azido cyclic Arg-Gly-Asp (cRGD) peptide as a model system in very high RCY of 98 %.
A bio-orthogonal functionalization strategy for site-specific coupling of antibodies on vesicle surfaces after self-assembly
2019
Attaching targeting ligands on the surface of self-assembled drug delivery systems is the key request for a controlled transport of the drug to a desired location. Most commonly, the amphiphilic molecules (blockcopolymers, lipids etc.) are therefore pre-functionalized before the self-assembly takes place. However, this strategy cannot be applied, if it interferes with the self-assembly process, if the introduced functional groups react with loaded cargo or if natural carriers like extracellular vesicles should be functionalized. Here, we present the site-specific coupling of antibodies to the surface of amino group-terminated liposomes via bio-orthogonal copper-free click chemistry after li…
Cellulose-click-ferrocenes as docking spots for cyclodextrin
2012
A novel synthesis of ferrocene-modified cellulose, prepared from 6-azido-6-deoxy-cellulose and ethynylferrocene, is presented. The two components were coupled via copper-catalyzed click-type cycloaddition under microwave-assisted conditions. The surface structure of the cellulose derivative was investigated in comparison with that of pure, microcrystalline cellulose using electron microscopy (scanning, transmission and scanning transmission), showing iron atoms of ferrocene as homogeneously distributed particles. They are detectable as clear signals in the energy-dispersive X-ray profile. In addition, Rame-β-cyclodextrin was supramolecularly attached to cellulose and the complex formed was …
Architecture, self-assembly and properties of well-defined hybrid polymers based on polyhedral oligomeric silsequioxane (POSS)
2013
Abstract Well-defined hybrid polymers based on polyhedral oligomeric silsequioxane (POSS) with a variety of architectures have been developed, including telechelic polymers, block copolymers and star-shaped polymers. The synthesis, self-assembly and properties of this kind of materials are reviewed. Well-defined POSS-containing hybrid polymers can be constructed by living polymerization techniques, such as ring-opening polymerization and living free-radical polymerization or the combination of living polymerization and coupling reactions, such as click chemistry and hydrosilylation. The self-assembly behavior of well-defined POSS-containing hybrid polymers is also described in detail. The P…
Functionalization of Porous Polymers from High‐Internal‐Phase Emulsions and Their Applications
2012
Post-Polymerization Modification
2012
The synthesis of functional polymers has been enriched dramatically by post-polymerization modifications. Even though it represents a synthetically very appealing approach, different synthetic concepts of organic reactions are utilized in polymer science for the synthesis of architecturally well-defined multifunctional polymers. The different classes of reactions that provide the synthetic polymer chemist with tools of unprecedented precision, thereby opening the doors for materials synthesis in an interdisciplinary world, will be summarized.