Additional pyrrolomycins from cultures of Streptomyces fumanus.

Along with dioxapyrrolomycin (1), four new pyrrolomycin antibiotics, namely, pyrrolomycin G (3), pyrrolomycin H (4), pyrrolomycin I (5), and pyrrolomycin J (6), were produced in cultures of Streptomyces fumanus. Apart from dioxapyrrolomycin, pyrrolomycin G and pyrrolomycin H are the only other chiral members of the pyrrolomycin family of antibiotics, and their absolute stereochemistry was deduced to be 13S. Here, we report the isolation, structure elucidation, and antimicrobial activity of these new pyrrolomycins.