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 1N sodium hydroxide aqueous solution (154 ml.) under ice-cooling and stirring. The mixture was further stirred for 10 minutes and then neutralized with 1N 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