反应详情

A mixture of ethyl 4-chloro-6-ethoxy-1,5-naphthyridine-3-carboxylate (3.1 g), 4-methoxyaniline (1.36 g) and IMS (40 ml) was boiled under reflux for 4 hours. The mixture was evaporated to dryness. The residual solid was ground in ether and then filtered. The solid was dissolved in dichloromethane and purified by column chromatography on silica using dichloromethane, then ether, then ethyl acetate, then IMS, as the mobile phase. The third fraction obtained was dissolved in IMS (30 ml) and the solution was saturated with hydrogen chloride gas. Ether was added and the mixture left to stand at approximately 4° C. for 3 days. The mixture was filtered to give ethyl 6-ethoxy-4-(4-methoxyanilino)-1,5-naphthyridine-3-carboxylate hydrochloride hydrate, m.p. 130°-133° C. Active (3/3) at 30 mg/kg.

1. temperatureunder reflux for 4 hours
2. customThe mixture was evaporated to dryness
3. filtrationfiltered
4. dissolutionThe solid was dissolved in dichloromethane
5. custompurified by column chromatography on silica
6. customThe third fraction obtained
7. waitthe mixture left
8. filtrationThe mixture was filtered