351029-87-3Relevant articles and documents
Pyridopyrimidines. X. Synthesis of 3-substituted 2-thioxo-5,7-dimethylpyrido[2,3-d]pyrimidin-4(3H)-ones and their S-alkylation under phase transfer conditions
Dave,Patel
, p. 457 - 461 (2001)
2-Thioxo-5,7-dimethylpyrido[2,3-d]pyrimidin-4(3H)-ones 3 were synthesized by the cyclocondensation of 2-amino-3-carbethoxy-4,6-dimethylpyridine 1 with methyl-N-aryldithiocarbamates 2 and compared with the condensation between 1 and aryl isothiocyanates 4. When a comparative study of N vs S alkylation of ambident 2-thioxo-5,7-dimethylpyrido[2,3-d]pyrimidin-4(3H)-ones 3 was carried out under liquid-liquid and solid-liquid phase transfer conditions using various alkylating agents 5, the S-alkylated products 6 were obtained exclusively and selectively.