The biosynthetic origins of rebeccamycin

Experimental evidence is presented to demonstrate that the antitumor-antibiotic rebeccamycin is biosynthesized by Saccharothrix aerocolonigenes from one unit of glucose, one of methionine, and two of tryptophan. Evidence is presented that suggests that the alpha-amino group of neither tryptophan unit provides the nitrogen of the phthalimide system.