反应详情

1.71 g of 2-propyl-2-(3-thiazol-2-ylureido)pentanoic acid ethyl ester (product from Example lA, stage 4) were combined with 30 ml of 30% hydrochloric acid. The mixture was refluxed for three hours. Once the mixture had cooled, the pH was adjusted to an alkaline value with potassium carbonate, extraction was performed three times with ethyl acetate, the mixture washed twice with a saturated common salt solution and dried over sodium sulphate. The crude product obtained by the subsequent removal of the solvent by distillation was purified by passage through a silica gel column with ethyl acetate. 0.62 g of 5,5-dipropyl-3-thiazol-2-yl-2,4-imidazolidinedione (42% of th.) were obtained.

1. temperatureThe mixture was refluxed for three hours
2. temperatureOnce the mixture had cooled
3. extractionthe pH was adjusted to an alkaline value with potassium carbonate, extraction
4. washthe mixture washed twice with a saturated common salt solution
5. dry with materialdried over sodium sulphate
6. customThe crude product obtained by the subsequent removal of the solvent by distillation
7. customwas purified by passage through a silica gel column with ethyl acetate