Oligo moiety

Many proteins found in nature are glycoproteins because they contain covalently linked oligo- and polysaccharide groups. The list of known glycoproteins includes structural proteins, enzymes, membrane receptors, transport proteins, and immunoglobulins, among others. In most cases, the precise function of the bound carbohydrate moiety is not understood. 

At Kodak, researchers used a rigid adamantane moiety to separate the luminescent oligo(phenylene vinylene) blocks (copolymers 182, 183) [213], The EL color can be tuned from blue (AEL = 470 nm) to green (AEL = 516 nm) by replacing a phenylene unit in 182 for 2,7-naphthylene (183). A very low turn-on voltage of 5.5 V (as for this class of materials) was achieved in the device ITO/182/Mg Ag, but no EL efficiency was reported (Chart 2.40). 

Irradiation of 2,3-diphenyl-2//-azirine in the presence of fullerene leads to the formation of mono- and oligo adducts (98,99). A monoadduct, l,9-(3,4-dihydro-2,5-diphenyl-2//-pyrrolo)fullerene-60 was isolated and characterized. Mechanistic studies showed that under conditions of direct irradiation it was formed by a classic nitrile ylide cycloaddition but in the presence of 1,4-napthalenedicarbonitrile (DCA) it resulted from reaction of the radical cation intermediate 108. Cycloaddition reactions have also been carried out with diaza-phospholes and diazaarsoles (100) to give adducts of the type 189 (A = As,P) and with cyanogen to give 190 and with aryldiazocyanides where addition to both the azo moiety and the cyano group were observed (101). 

Follow-on functionalisation with molecular moieties of biological importance, such as anti-tumour agents (e.g. 5-fluorouracil) currently appears particularly attractive. In this context, acetylation is particularly suitable as functionalisation reaction for oligo/polyamine dendrimers. It renders the dendrimers more water soluble, which is essential for biomedical applications [25]. The toxicity of den-... 

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