Total Synthesis of the Photoprotecting Dipyrrolobenzoquinone (+)-Terreusinone

The first synthesis of (+)-terreusinone 1, a dipyrrolobenzoquinone with a potent UV-A protecting capability, is described. Key transformations include a one-pot Larock indolization–Sonogashira coupling reaction and the hydroamination of an unsubstituted ortho-alkynylaniline catalyzed by a cationic gold(I) complex. The synthesis proceeds in eight steps from commercially available starting materials, confirming the structure and absolute configuration of the natural product.