Dimeric hexahydropyrroloindole alkaloids

Fig. 9.1 Representative dimeric hexahydropyrroloindole alkaloids, (a) Dimeric epipolythiodiketopiperazine alkaloids, (b) Calycanthaceous alkaloids, (c) Dimeric diketopiperazine alkaloids...

These epipolythiodiketopiperazine alkaloids, together with the calycanthaceous alkaloids (Fig. 9.1b), form a superfamily of natural products termed the dimeric hexahydropyrroloindole alkaloids [6-8]. The main dichotomy within this superfamily arises from the biogenetic elaboration of tryptamine versus tryptophan building blocks. The tryptamine-based calycanthaceous alkaloids, boasting members such as chimonanthine (7), calycanthine (9), and folicanthine (8), are largely plant derived and have a long and rich history in the context of natural product synthesis [7, 9]. 

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