反应详情

C-4. 1,2-Dihydro-6-methyl-5-(2-methyl-4-thiazolyl)2-oxo-3-pyridinecarboxylic acid--A mixture containing 32 g of 1,2-dihydro-6-methyl-5-(2-methyl-4-thiazolyl)-2-oxo-3-pyridinecarboxamide, 50 ml of 35% aqueous sodium hydroxide solution and 300 ml of water was heated on a steam bath for 15 hours and cooled. The reaction mixture was filtered to remove a small quantity of insoluble material and the filtrate was acidified with concentrated hydrochloric acid. The resulting precipitate was collected, washed with water and dried in an oven at 80° C. to produce 30.2 g of 1,2-dihydro-6-methyl-5-(2-methyl-4-thiazolyl)-2-oxo-3-pyridinecarboxylic acid, m.p. 297°-299° C. with decomposition.

1. temperaturewas heated on a steam bath for 15 hours
2. temperaturecooled
3. filtrationThe reaction mixture was filtered
4. customto remove a small quantity of insoluble material
5. customThe resulting precipitate was collected
6. washwashed with water
7. customdried in an oven at 80° C.