Isocyanide-derived amide, electrophile

Another electrophile that can interact with the isocyanide-derived amide is an aldehyde. However, an additional carbonyl function cannot be introduced as such into one of the components without interfering with the Ugi process. Thus it is better used in masked form as an acetal (Fig. 9). Starting from amine 49 a series of oxopiperazines 51 has been prepared, also on solid phase [66],... 

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