Efficient method for the synthesis of pyridopyrimidin-5-ones from 4-amino-5-acetylpyrimidines

Article abstract of DOI:10.1007/BF00703702

New method for annelation of a pyridine ring to a pyrimidine ring were suggested.Substituted 8H-pyrido<2,3-d>pyrimidin-5-ones (8a-f) were synthesized by the interaction of 2,6-disubstituted 4-amino-5-acetylpyrimidines (1-4) with formamide or acetamide acetals followed by cyclization under the action of sodium methoxide in methanol. 2,4-Disubstituted 7-phenyl-8H-pyrido<2,3-d>pyrimidin-5-ones (11a-c) were propared by the reaction of 2,6-disubstituted 5-acetyl-4-benzoylaminopyrimidines (10a-c) with MeONa in boiling BuOH. - Key words: 4-amino-5-acetylpyrimidines, 4-benzoylamino-5-acetylpyrimidines, dimethylformamide dimethylacetal, dimethylacetamide dimethylacetal, pyrido<2,3-d>pyrimidin-5-ones.