Streptamine isomers

Ito and co-workers have reported the synthesis of ribostamycin from 3, 4 -dibenzyl-tetra-N-(benzyloxycarbonyl)-neamine and 2,3,5-tri-O-benzyl-D-ribofurano-sylchloride (Sect. III.2.). An alternative synthesis of ribostamydn and biologically inactive isomers starts with 4-acetyl-N,N -dicarbo-benzoxy-2-deo3 streptamine, which reacts with 2,3,4-tri-O-benzoyl-D-ribofurano l chloride in the presence of AgC104-Ag2C03 to the tricyclic 5-0-j3-D-ribofurano l-2-deoxystreptamine Butirosin has been synthesised by S. Umezawa and co-workeis from protected ribostamycin (Sect. III.2.3). 

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