A Bidirectional Synthesis of (+)-Terreusinone

An efficient, bidirectional synthesis of the photoprotecting dipyrrolobenzoquinone (+)-terreusinone has been accomplished. Key steps include a copper-and amine-free double Sonogashira reaction of an electron-rich 1,4-dibromide with a protected propargylic alcohol followed by pyrrolo[2,3-f]indole formation by double hydroamination catalyzed by Echavarren's cationic gold(I) complex. This new route to (+)-terreusinone complements the original synthesis and offers advantages over its predecessor.