Scheme 5. Pathways from anthraquinones to benzophenones. (A) The conversion of questin 9 to desmethylsulochrin 16 in the geodin biosynthetic pathway, showing the likely mechanism of the cofactor free dioxygenase GedK. Based on the proposal by Lu and colleagues.75 (B) The likely route from emodin 1 to chrysophanol 2, monodictyphenone 12 and the later prenylated xanthones in Aspergillus nidulans.
