摘要 |
A purified isolate of an actinomycete identified as ATCC 39363 is capable of producing a complex of sulfur-containing antibiotic compounds having activity against transplanted tumors. Antibiotic compounds CL-1577A and CL-1577B and their closely related congeners are produced by cultivating isolate ATCC 39363 under aerobic conditions in a culture medium containing assimilable sources of carbon and nitrogen until a substantial quantity of the CL-1577 complex is produced, and subsequently isolating the complex or one or more of the compounds. The antibiotic compounds CL-1577A, CL-1577B, their congeners, and pharmaceutical compositions comprising these substances together with a suitable carrier are also disclosed. |