Ketopremithramycins and ketomithramycins, four new aureolic acid-type compounds obtained upon inactivation of two genes involved in the biosynthesis of the deoxysugar moieties of the antitumor drug mithramycin by Streptomyces argillaceus, reveal novel insights into post-PKS tailoring steps of the mithramycin biosynthetic pathway - Remsing, L L; García-Bernardo, J; González, A; Künzel, E; Rix, U; Braña, A F; Bearden, D W; Méndez, C; Salas, J A; Rohr, J (J Am Chem Soc, 2002)