Suitably Functionalized Carbohydrate Precursors

Tert-butyl calix[4]arene possessing four antennary amine groups (7) were initially synthesized from commercially available phenolic tert-butyl calix[4]arene according to a published procedure [13]. After derivatization of the phenolic group by alkylation with ethyl bromoacetate, hydrolysis, acid 

5 GLYCODENDRIMERS BASED ON POLY(AMIDOAMINES) (PAMAM) DENDRIMERS 

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Let us turn to answering the second question first. Potential precursors of dehydroalanine, by way of -elimination, are the amino acids with functional groups at the /3-carbon atom. Such -elimination reactions are likely to be enzyme-catalyzed in nature. Additionally, the substrates may be suitably substituted at functions, such as the sulfhydryl group (thioether and sulfonium salt formation) or the hydroxyl group (carbohydrate attachment—glycopeptides and proteins phosphorylation). 

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