RING TRANSFORMATIONS OF SOME 4-AMINOPTERIDINE 3-OXIDES AND DERIVATIVES

Article abstract of DOI:10.1016/S0040-4020(01)91861-7

Syntheses of 4-aminopteridine 3-oxides are described.The pyrimidine part undergoes transformations with various reagents to give 4-hydroxyaminopteridines, substituted pyrazines, or substituted 1,2,4-oxadiazolylpyrazines. s-Triazolo(1,5-a)pyrazines can be prepared from 1,2,4-oxadiazolylpyrazines.The ring opening of the pyrimidine part of pteridines proceeds either py a C₂-N₃ or N₃-C₄ bond cleavage.