Reactions of 2-methyl-4H-pyrido[2,3-d][3,1]oxazin-4-one with active methylene compounds: A new efficient route to 3-substituted 4-hydroxy-1,8-naphthyridin-2(1H)-ones
Reactions of 2-methyl-4H-pyrido[2,3-d][3,1]oxazin-4-one with active methylene compounds: A new efficient route to 3-substituted 4-hydroxy-1,8-naphthyridin-2(1H)-ones
(EN)
Delieza, V
(EN)
Detsi, A
(EN)
Igglessi-Markopoulou, O
(EN)
Bardakos, V
(EN)
3-Substituted 1,8-naphthyridine-2,4-diones, compounds of very important pharmaceutical use, have been synthesized using a new efficient route. The reaction of 2-methyl-4H-pyrido-[2,3-d][3,1]oxazin-4-one, 1b, with active methylene compounds furnishes the 1-acetyl-3-substituted-4-hydroxy-1,8-naphthyridin-2-ones 3-5, in good yields. In the case of cyanoacetic esters the intermediate C-acylation compounds 7 and 8 were isolated and subsequently cyclized to 1-acetyl-3-cyano-4-hydroxy-1,8-naphthyridin-2-one 6. Spectral data and physical characteristics for all compounds are reported.
(EN)