Biomimetic Synthesis: Discovery of Xanthanolide Dimers

Starting from xanthatin, the biomimetic synthesis of 4β,5β‐epoxyxanthatin‐1α,4α‐endoperoxide, a novel monomeric xanthanolide, has been achieved. Moreover, four unprecedented xanthanolide dimers were synthesized by three different dimerizations of xanthatin, either in a head‐to‐head or head‐to‐tail fashion. Notably, these dimeric compounds were firstly identified as artifacts in the laboratory, and two of them, mogolides A and B, proved to be natural products present in the Xanthium mogolium Kitag plant.