Reactions click

Huang J, Habraken G, Audouin F, Heise A (2010) Hydrolytically stable bioactive synthetic glycopeptide homo- and copolymers by combination of NCA polymerization and click reaction. Macromolecules 43 6050-6057... 

By combining several click reactions, click chemistry allows for the rapid synthesis of useful new compounds of high complexity and combinatorial libraries. The 2-type reaction of the azide ion with a variety of epoxides to give azido alcohols has been exploited extensively in click chemistry. First of all, azido alcohols can be converted into amino alcohols upon reduction.70 On the other hand, aliphatic azides are quite stable toward a number of other standard organic synthesis conditions (orthogonality), but readily undergo 1,3-dipolar cycloaddition with alkynes. An example of the sequential reactions of... 

Another important click reaction is the cycloaddition of azides. The addition of sodium azide to nitriles to give l//-tetrazoles is shown to proceed readily in water with zinc salts as catalysts (Eq. 11.71).122 The scope of the reaction is quite broad a variety of aromatic nitriles, activated and nonactivated alkyl nitriles, substituted vinyl nitriles, thiocyanates, and cyanamides have all been shown to be viable substrates for this reaction. The reaction of an arylacetylene with an azide in hot water gave 1,4-disubstituted 1,2,3-triazoles in high yields,123 while a similar reaction between a terminal aliphatic alkyne and an azide (except 111 - nitroazidobenzcnc) afforded a mixture of regioisomers with... 

Xie F, Sivakumar K, Zeng Q et al (2008) A fluorogenic click reaction of azidoanthracene derivatives. Tetrahedron 64 2906-2914... 

Wolfbeis, O. S. (2007). The click reaction in the luminescent probing of metal ions, and its implications on biolabeling techniques. Angew. Chem. Int. Ed. Engl. 46, 2980-2. 

Click chemistry refers to the reaction between an azido functional group and an alkyne to form a [3 + 2] cycloaddition product, a 5-membered triazole ring. This reaction has been used for many years in organic synthesis to form heterocyclic rings. Normally, the click reaction requires high temperatures, and this was the main reason that it was not used as a bioconjugation tool. However, it was discovered that in aqueous solutions and in the presence of Cu(I), the reaction kinetics are dramatically accelerated to provide high yields even at room temperature and ambient pressures (Rostovtsev et al., 2002 Tornoe et al., 2002 Sharpless et al., 2005). 

The advantage of the click reaction for bioconjugation is that the reactant pair is not reactive with any other functional group encountered in biological systems. This property of... 

Another source for Cu(I) in the click reaction is to use elemental copper metal filings, which generate Cu(I) ion in solution slowly by oxidation. This last option, however, is considerably slower in generating the necessary Cu(I) than the other methods and will result in reactions needing to be done for at least 24 hours. 

For click reactions done in complex solutions, such as in the presence of biological molecules, the amount of Cu(II) and ascorbate addition typically is at a concentration of at least 0.1 mM CuSC>4 and 0.2 mM ascorbate. In this type of environment, the labeling reaction usually is done on azide or alkyne targets at very low concentration levels and for extended times. At this concentration of metal salt and ascorbate, cells may not remain viable for long periods and may die. 

Carbon nanotubes have been decorated with metal nanoparticies of Au, Ag, Pt, Pd and Co employing different procedures such as the click reaction [107], microwave treatment [106], electroless plating [108] and laser irradiation of mixtures of the individual components [109]. Pt-carbon nanotube hybrids have been used as catalysts for the conversion of nitrobenzene to aniline [110]. Tessonier et al. report that MWNTs covered with Pd nanoparticies on the interior walls can be employed for... 

Following reports of efficient Cu(I)-catalyzed alkyne/azide cycloaddition on solid phase and in solution by Meldal [42] and Sharpless [43], respectively, the formerly obscure Huisgen reaction soared to prominence as a versatile tool for covalent chemical ligation. The so-called click reaction can be catalyzed by a number of copper sources in a variety of media (Equation 9.14). 

Scheme 12.20 Over 104 fold rate acceleration of the click reaction by cucurbit[6]uril.28...

Click chemistry has been used extensively since its introduction in organic chemistry, due to the high efficiency and technical simplicity of the reaction [40]. The most popular click reaction has been the copper-catalyzed dipolar cycloaddition of a terminal alkyne and an azide to form... 

Fig. 7 Synthesis of cyclic PNIPAM using Click reaction...

The most important part (and the most difficult and error prone) is setting up the reactions. Click Reactions on the left column of the Data Browser window and click Reactions... 

Table 23 Summary of the 20 click reactions conducted within a PDMS microreactor, highlighting those which were identified to be a hit...

Figure 8.4. Main window of Gepasi. The main window of Gepasi consists of menus (File, Options, and Help), icons, and four tabs (Model definition, Tasks, Scan, and Time course). Activation of any of the tab opens an indexed page. At the start of Gepasi, the Model definition page is opened. Enter name of the metabolic pathway to the Title box. Click Reactions button to define enzymatic reactions (e.g., E + A+B = EAB for R1, EAB = EPQ for R2, and EPQ = E + P + Q for R3 shows 3 reactions and 7 metabolites), and then click Kinetics button to select kinetic type. Activate Tasks tab to assign Time course (end time, points, simufile.dyn), Steady state (simufile.ss) and Report request. Activate Scan tab to select scan parameters. Activate Time course tab to select data to be recorded and then initiate the time course run.

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