Alkyne or azide group

Another ABPP platform integrates click chemistry (CC), where an alkyne or azide group in the ABP acts as a latent attachment point for a reporter tag [34,35]. Replacing bulky reporter groups with an alkyne extends ABP design to include probes that function in live cells and... 

In state-of-the-art carbohydrate chemistry, the introduction of the alkyne or azide group in a sugar is a routine process that allows easy access to mono-as well as polyfunctionaUzed derivatives. These compounds can be rationally used for the conjugation with other complementary functionaUzed molecules... 

A number of unimolecular alkoxyamines containing alkyne or azide functional groups have also been reported and used in postpolymerization Huisgen cycloaddition reactions. Gungor et reported an alkyne-functionalized... 

In the previously discussed click methodologies, the azide and aUcyne reactants were S3mthesized and isolated before their use in the CuAAC reaction. In an effort to further improve the synthetic efficiency and safety of the CuAAC reaction, a number of groups have developed one-pot CuAAC methodologies in which either the alkyne or azide reactant is generated in situ and reacted immediately without isolation and purification. 

Campidelli et al. have synthesized interesting linear and hyperbranched porphyrin polymers from CNTs via copper-catalyzed alkyne-azide cycloaddition (CuAAC) [122], Zinc porphyrin monomers containing an azide group and one or three alkyne groups were synthesized and chemically bound to alkyne functionalized SWCNTs via CuAAC. Depending upon the number of alkyne functionalities either linear (single alkyne) or dendrimer-like (triple alkyne) porphyrin polymers were produced (Fig. 5.9) [122],... 

It looks as if the more nucleophilic end of the azide has attacked the wrong end of the alkyne but we must remember that (1) it is very difficult to predict which is the more nucleophilic end of a 1,3-dipole and (2) it may be either HOMO (dipole) and LUMO (alkyne) or LUMO (dipole) and HOMO (alkyne) that dominate the reaction. The reason for doing the reaction was to make analogues of natural nucleosides (the natural compounds are discussed in Chapter 49). In this case the OH group was replaced by a cyanide so that a second aromatic ring, a pyridine, can be fused on to the triazole. 

Fig. 10.3-19 Modification of proteins using "Click chemistry, (a) Sixty azide groups were introduced on the surface of the cowpea mosaic virus (CPMV) through the alkylation of genetically introduced cysteine residues. These groups can be modified through exposure to alkynes, Cu(l) (the Cu(ll) source is reduced in situ by theTCEP), and ligand 58 or 59. Similar results were...

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