Naphthoquinones are characteristic constituents that have been detected in numerous plant families. There are at least four fundamentally different biosynthetic routes that lead to the naphthoquinone skeleton. Some naphthoquinones are formed via the acetatepolymalonate (= polyketide) pathway, and plant families notoriously known for containing such acetogenins are Iridaceae, Ebenaceae, Plumbaginaceae, Droseraceae, Nepenthaceae, Drosophyllaceae, Dioncophyllaceae, and Ancistrocladaceae. While all these families include species that form plumbagin (= 2-methyljuglone), its regioisomer 7-methyljuglone (= ramentaceone) has so far only been detected in Ebenaceae, Nepenthaceae, and Droseraceae.