| Abstract: | Danoxamine, the Iron-Binding Moiety of the Sideromycin Antibiotic Danomycin The antibiotic danomycin was separated into its components, danomycin A and B ( 1 and 2 , resp.), by various methods. Danomycin A is a carbamate of danomycin B and can be transformed to the latter by boiling with H2O. Both danomycins can be hydrolyzed by alkali to the Fe-containing moiety, danoxamine ( 3 ). The structure of the latter was determined by spectroscopy and chemical degradation as the Fe(III) complex of 5,16,27,32-tetrahydroxy-4,12,15,23,26-pentaoxo-5,11,16,22,27-pentaaza-dotriacontanoic acid. It belongs thus to the ferrioxamine family of siderophores. In the danomycins, this moiety is linked by an ester bond to a disaccharide moiety of unknown structure. One of the sugars is believed to be an aminohexane methyl ether. Chromatographically homogenous danomycins A and B are still mixtures of isomers, a neutral sugar being glucose or mannose. |
