BIOSYNTHETIC STUDY AND RADIOISOTOPE LABELING OF INOSTAMYCIN

To obtain radioactively labeled inostamycin, the biosynthesis of inostamycin was studied by feeding experiments with C-13-labeled precursors. From the (1)3C-nmr spectrum of inostamycin enriched from incorporation of [1-C-13]propponate, [1-C-13]bucyrate, and [1-C-13]acetate, it was shown to be derived from six propionate and five butyrate units. Radioactively labeled inostamycin was prepared biosynthetically with [1-C-14]propionate. As a result, [C-14]inostamycin of 2.97 mCi/mmol was prepared. Using this labeled inostamycin, its accumulation in NRK cells was examined.