反应详情

1,1-Dimethylethyl 4-[5-(methoxycarbonyl)-2-thiazolyl]-1-piperazinecarboxylate (i.e. the product of Example 4, Step A) (2.56 g, 8 mmol) in 15 mL of methanol and 15 mL of tetrahydrofuran was added 1 N aqueous NaOH solution (10 mL), and the mixture was stirred at ambient temperature overnight. The mixture was concentrated under reduced pressure, diluted with water, washed with ether, and acidified with excess 20% aqueous citric acid solution to give a precipitate. The precipitate was filtered, washed with water and dried to give 2.12 g of the title compound as a slightly pink solid.

1. concentrationThe mixture was concentrated under reduced pressure
2. additiondiluted with water
3. washwashed with ether
4. customto give a precipitate
5. filtrationThe precipitate was filtered
6. washwashed with water
7. customdried