Definition of Cascade Reactions

The first type of cascade reaction is sequential synthesis which describes the usage of multiple consecutive catalytic steps for building up complex stractures. Each step may be performed under different reaction conditions however, no purification of the intermediate products is necessary. Herein chemical catalytic steps may be combined with enzymatically catalyzed ones or the cascade may be operated with enzymes solely. 

One-pot synthesis focuses on the combination of multiple catalytic steps in one reaction vessel under the same reaction conditions. Optimization of the reaction conditions to suit all involved catalysts is crucial to reach shorter reactions times than for the sequential reaction type. Again, here the combination of chemical steps and enzymatic steps in one-pot is possible. 

The last reaction type covers convergent reactions. They involve separate catalytic pathways yielding different products that are finally combined to the desired one. Each of the pathways may include cascade reactions in themselves. 

In this chapter, we take a look at the synthesis, modification, and regeneration of activated sugar donors. Further examples like state of the art synthesis of epitopes involving multiple enzymatic and chemical steps are presented. Here, mainly two 

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