Synthesis of Marine Alkaloids from the Oroidin Family

Oxidation with a difference: The complexity of the oroidin alkaloid family of marine natural products is generated biosynthetically from one simple alkene precursor, but has left the synthetic community with problems. The first total synthesis of the tetracyclic axinellamines (see structure) was recently completed. Key to the success was the chemoselective oxidative functionalization of imidazol(in)e rings (green).