Abstract: A purified isolate of an actinomycete identified as ATCC 39366 is capable of producing the anti-microbial compound CL-1957B which also exhibits antitumor properties.The antimicrobial compound CL-1957B is produced by cultivating isolate ATCC 39366 under aerobic conditions in a culture medium containing assimilable sources of carbon and nitrogen until a substantial quantity of the CL-1957B compound is produced, and subsequently isolating the compound.The antibiotic compound CL-1957B, its pharmaceutically acceptable salts, the pharmaceutical compositions comprising this substance together with a pharmaceutically acceptable carrier is also disclosed, as are methods of treating microbial infections and tumors in mammals, employing these pharmaceutical compositions.

Abstract: A purified isolate of an actinomycete identified as ATCC 39366 is capable of producing the anti-microbial compound CL-1957A which also exhibits antitumor properties.The antimicrobial compound CL-1957A is produced by cultivating isolate ATCC 39366 under aerobic conditions in a culture medium containing assimilable sources of carbon and nitrogen until a substantial quantity of the CL-1957A compound is produced, and subsequently isolating the CL-1957A compound.The antibiotic compound CL-1957A and pharmaceutical compositions comprising this substance together with a pharmaceutically acceptable carrier is also disclosed, as are methods of treating microbial infections and tumors in mammals, employing these pharmaceutical compositions.

Abstract: 2'-Chloropentostatin is a potent inhibitor of the enzyme adenosine deaminase and possesses utility as an agent for potentiating the activity of antiviral agents for the treatment of DNA viruses which agents contain an adenine moiety, such as 9-(beta-D-arabinosyl)adenine. A pure strain of actinomycete, designated ATCC 39365 which is capable of producing 2'-chloropentostatin, a method of producing 2'-chloropentostatin by aerobic fermentation, and pharmaceutical compositions including 2'-chloropentostatin are also disclosed.

Abstract: A strain of actinomycete, NRRL 15758, is capable of producing the CL-1724 complex of compounds under conditions of aerobic fermentation in the presence of assimilable sources of carbon and nitrogen. The compound CL-1724B-2 exhibiting antimicrobial and antitumor activity, is claimed together with pharmaceutical compositions and methods of treating microbial infections and tumors in mammals employing these pharmaceutical compositions.

Abstract: Compounds CL-1577D and CL-1577E are prepared by cultivation of a purified isolate of Actinomycete designated ATCC 39363 in a culture medium having assimilable sources of carbon and nitrogen. The compounds are effective antimicrobial agents and possess cytotoxic activity against L1210 murine leukemia cells and P388 murine leukemia cells.