| abstract |
Described is a new microorganism, Actinoplanacete sp., (Merck Culture Collection MA 6559) ATCC No. 53771. The microorganism acts as a demethylating agent and can produce the new immunosuppressants, "demethomycin" (L-682,993) a C-31 demethylated analog of L-679,934, and "demethimmunomycin" (L-683,742) a C-31 demethylated analog of L-683,590, under novel fermentation conditions. These macrolide immunosuppressants are useful in preventing human host rejection of foreign organ transplants, e.g. bone marrow and heart transplants. |