ABSTRACT
The actinomycins, a family of structurally related chromopeptide antibiotics with a common phenoxazinone chromophore attached to two pentapeptide lactone moieties (Figure 15.1), vary in their amino acid content (Table 15.1). They emerged from the pioneering work of Selman Waksman on soil microorganisms, and in particular from his work on the Streptomyces. The œrst actinomycin, isolated in 1940 from Streptomyces antibioticus,1,2 was the œrst of several antibiotics discovered by Waksman, the œrst crystalline antibiotic, and the œrst to display antitumor activity. Many other actinomycins have since been isolated from other Streptomyces species, and it was also found in an unrelated genus, Micromonospora.3
