1. Field of the Invention
This invention relates to novel antibiotic compounds designated BU-3292T A and B. The compounds possess antimicrobial and antitumor activities.
2. Description of the Prior Art
Elucidation of the structure of BU-3292T A revealed that it had a unique depsipeptide structure. This type of pentapeptide lactone has been proposed as a key intermediate in the biosynthesis of actinomycin (Katz. E: Antibiotics, Vol. II. Biosynthesis, p. 276, Springer-Verlay, Berlin, 1967), but none of such monomer type compound has so far been discovered in the microbial metabolites.
Actinomycin Z.sub.5 (Tetrahedron Letter, 2567, 1973) and Schering 1a and 1b (15th Interscience Conference on Antimicrobial Agents and Chemotherapy, Abstract No. 419) are reported to each contain one mole of 5-methylproline. BU-3292T B differs from these actinomycins in that it has two moles of 5-methylproline forming two identical peptide lactone side chains.