Synthesis of 4-aminopyrazolo[3,4-d]pyrimidine derivatives from 5-acetyl-6-amino-4-methylsulfanyI- or 5-acetyl-6-amino-4-methylsuIfonylpyrimidines

摘要

Diacetyl ketene N,S-acetal was used for the synthesis of 5-acetyl-6-amino-4-methyl-sulfanylpyrimidines substituted at the exocyclic nitrogen atom, which were further oxidized with m-chloroperbenzoic acid to the corresponding methylsulfonylpyrimidines. Reactions of hydrazines with these pyrimidines containing vicinal Ac and MeS (or MeSO2) groups were used for the preparation of new 4-aminopyrazolo[3,4-d]pyrimidine derivatives.