Oxidative cleavage of premithramycin B is one of the last steps in the biosynthesis of the antitumor drug mithramycin - Prado, L; Fernández, E; Weisbach, U; Blanco, G; Quirós, L M; Braña, A F; Méndez, C; Rohr, J; Salas, J A (Chem Biol, 1999)