130812-07-6 6-De(2-oxoethyl)-6-(4-oxo-2-pentenyl)cirramycin A(sub 1) 6108D Antibiotic 6108D Cirramycin A(sub 1), 6-de(2-oxoethyl)-6-(4-oxo-2-pentenyl)- Cirramycin A1, 6-de(2-oxoethyl)-6-(4-oxo-2-pentenyl)-