Synthesis of bredinin 5'-alkylphosphates involving photochemical manipulation of the imidazole moiety, and their antitumor activities

Bredinin 5'-oleyl and 5'-cetyl phosphates (2a and 2b), prepared from 1-β-D-ribofuranosyl-5-aminoimidazole-4-carboxamide via a photochemical ring-opening reaction of the imidazole moiety, showed remarkable antitumor effects against various transplantable mouse tumors, and were clearly superior to bredinin (1).