N-Amination of aromatic heterocyclic amines has been accomplished with a number of reagents. 19g20 We found that 4 was not reactive with 0-2, 4-dinitrophenoxyamine, 21g22 but the reaction of 4 with 0-mesitylenesulfonylhydroxylamine23~ 24 afforded the mesitylate salt of 1, 2-diamino-4-PD-ribofuranosylpyrazin-2-one (5) in 77% yield. This was converted to the chloride salt 6 by ion-exchange chromatography. The structure of the N-amino ...
