The structure 1a is proposed for ravidomycin on the basis of chemical and spectroscopic data.
Full spectral details in support of the earlier proposed structure 1a for the antitumor antibiotic ravidomycin are presented together with an account of chemical degradation products. A complete corroboration of structure is provided by cross correlation of 1H and 13C nmr for ravidomycin and its diacetate 1b.