Spirotryprostatin B is an indolic alkaloid found in the Aspergillus fumigatus fungus that belongs to a class of naturally occurring 2,5-diketopiperazines.

The first total synthesis was accomplished in 2000 by the Danishefsky group at Columbia University,[3] with a number of other syntheses following shortly thereafter by Williams,[4] Ganesan,[5] Fuji,[6] Carreira,[7] Horne,[8] Overman,[9] and most recently Trost.

[10] From a synthetic point of view, the most challenging structural features of the molecule are the C3 spirocyclic ring juncture and the adjacent prenyl-substituted carbon.

A secondary amine was combined with an aldehyde to form an intermediate azomethine ylide, which underwent a 1,3-dipolar cycloaddition with an unsaturated oxindole also present in the reaction mixture.

An indole was treated with N-bromosuccinimide to trigger an oxidative rearrangement, forming the quaternary stereocenter in a diastereoselective manner.