反应详情

To a mixture of ethyl 2-[2-[3-(methyl)thioureido]-1,3-thiazol-4-yl]glyoxylate, which can be represented as ethyl 2-[2-[3-(methyl)thioureido]-2,3-dihydro-1,3-thiazol-4-yl]glyoxylate, (21 g.), ethanol (200 ml) and water (100 ml.) was added 1 N sodium hydroxide aqueous solution (154 ml.) under ice-cooling and stirring. The mixture was further stirred for 10 minutes and then neutralized with 1 N hydrochloric acid (154 ml.). The precipitates were collected by filtration, washed with water and then dried to give 2-[2-[3-(methyl)thioureido]-1,3-thiazol-4-yl]glyoxylic acid, which can be represented as 2-[2-[3-(methyl)thioureido]-2,3-dihydro-1,3-thiazol-4-yl]glyoxylic acid, (17.8 g.), mp.>250° C.

1. temperaturecooling
2. stirringThe mixture was further stirred for 10 minutes
3. filtrationThe precipitates were collected by filtration
4. washwashed with water
5. customdried