STUDIES ON PYRAZOLOPYRIMIDINE DERIVATIVES. XVIII. FACILE PREPARATION OF 1H-PYRAZOLOPYRIMIDIN-4(5H)-ONES

Article abstract of DOI:10.3987/COM-90-5407

Reaction of 5-amino-1-phenyl-1H-pyrazole-4-carboxamide (4) with the esters (3a-h) in the presence of sodium ethoxide in ethanol gave 1-phenyl-1H-pyrazolo<3,4-d>pyrimidin-4(5H)-one (1a) and its 6-substituted derivatives (1b-h).Similar treatment of 5-amino-1-methyl-1H-pyrazole-4-carboxamide (5) with 3a-h gave the 1-methyl-1H-pyrazolo<3,4-d>pyrimidin-4(5H)-ones (2a-h).