Abstract
New macrolide antibiotics YL-704 A1 and B1 were isolated from the culture broth of Streptomyces platensis subsp. malvinus MCRL 0388 and the structures of them were elucidated with physicochemical microanalyses including the mass spectrometry of their derivatives and the chemical degradation studies. The structure of the sixteen-membered aglycone was the same in YL-704 A1 and B1, while, the acyl groups of the sugar were isovaleryl and propionyl, respectively. Finally, dipropionyl YL-704 A1 was entirely identified with tripropionyl leucomycin A1.
