6'"-Deamino-6'"-hydroxy derivatives,as intermediates in the biosynthesis of neomycin and paromomycin.

Abstract
From broths of a neomycin producing Streptomyces fradiae and of a mutant of S. rimosus f. paromomycinus, respectively, 6''''''-deamino-6''''''-hydroxyneomycin and 6''''''-deamino-6''''''-hydroxyparomomycin were obtained and their structures established by mass and 13C-NMR spectroscopy and by the study of hydrolytic fragments. These new compounds, which are both present as 2 epimers at C-5'''''', are suggested as intermediates in the biosynthesis of the parent antibiotics. The place and the mechanism of the 5''''''-epimerization and of the 6''''''-amination are discussed.