Transition metals in organic synthesis -: Part 83#:: Synthesis and pharmacological potential of carbazoles

A series of carbazole derivatives with promising pharmacological properties has been prepared using either an iron-mediated or a palladium-catalyzed synthetic approach. The carbazole alkaloids carbazoquinocin C, carbazomadurin A and B, epocarbazolin A and B, neocarazostatin B, and carquinostatin A are antioxidants acting as free-radical scavengers. Thus, they represent potential lead compounds for the development of novel drugs against diseases initiated by oxygen-derived free radicals. Initiated by the first naturally occurring carbazole alkaloids with antituberculosis (anti-TB) activity, clausine K and micromeline, a study on the structure-activity relationships for anti-TB-active carbazole derivatives has been carried out. The 6-oxygenated carbazoles glycozoline and glycozolinine show antibiotic activity towards several microorganisms. The 7-oxygenated carbazole siamenol exhibits anti-HIV activity.