title: Studies on macrocyclic lactone antibiotics. VI. Skeletal structure of copiamycin.
abstract: Skeletal structure of copiamycin (1) (C54H95N3O17), a potent antifungal antibiotic, was determined from the physicochemical properties of this compound and of its degradation products. This compound consists of 32-membered polyhydroxy lactone ring, an alpha, beta-unsaturated ester group, as well as a side chain with a disubstituted guanidine moiety as its terminal. One of the hydroxyl groups (presumably at C-19) forms a hemiketal ring with the keto group at C-15, and another (at either C-21 or C-23) forms a hemiester with a malonic acid moiety.
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D055598:Chemical Phenomena; D002621:Chemistry; D006868:Hydrolysis; D007783:Lactones / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D010126:Ozone; D013237:Stereoisomerism; D013302:Streptomyces / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D007783:Lactones; C000507:copiamycin; D010126:Ozone