反应详情

A stirred mixture of 4 g. of 1-ethyl-1,2-dihydro-4-hydroxy-7-methyl-2-oxo-1,8-naphthyridine-3-carboxylic acid ethyl ester (prepared as in Example 1) and 30 ml. of 40% aqueous methylamine in 20 ml. of methanol was heated under reflux for 5 hours. The solution was cooled, diluted with 100 ml. of water and was acidified with glacial acetic acid. The precipitate which formed was collected, air dried and was recrystallized from heptane to give 1.9 g. of the title compound, m.p. 150°-4° C.

1. additionA stirred mixture of 4 g
2. temperatureunder reflux for 5 hours
3. temperatureThe solution was cooled
4. additiondiluted with 100 ml
5. customThe precipitate which formed
6. customwas collected
7. customair dried
8. customwas recrystallized from heptane
9. customto give 1.9 g