反应详情

2,2-Dimethyl-Propionic acid 4-(4-isopropyl-piperazine-1-carbonyl)-thiazol-2-ylmethyl ester. The crude product from Step A (6.42 g, 24.2 mmol), 1-isopropyl-piperazine dihydrochloride (5.36 g., 26.68 mmol) and 1-hydroxybenzotriazole (4.915 g., 36.38 mmol) were dissolved into a mixture of N-methylmorpholine (14.72 g., 101.20 mmol) and DCM (120 mL). The mixture was stirred for 30 min under nitrogen. 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (6.97 g, 36.4 mmol) was added, and the reaction mixture was stirred for 18 h at rt. The reaction was quenched by the addition of 1 M NaOH (25 mL), and was stirred for 1 h. The mixture was diluted with water and extracted with DCM (3×60 mL). The combined organic extracts were washed with H2O, dried over Na2SO4, filtered, and concentrated to yield dark brown crude oil (6.2 g). The crude product was purified on silica gel column using 30-50% acetone-DCM to give the title compound as a brown oil (3.9 g, 46%). 1H NMR (500 MHz, CDCl3): 7.89 (s, 1H), 5.38 (s, 2H), 3.90-3.84 (m, 2H), 3.81-3.75 (m, 2H), 2.75-2.69 (m, 1H), 2.62-2.50 (m, 4H), 1.27-1.23 (s, 9H), 1.05 (d, J=6.3, 6H).

1. stirringthe reaction mixture was stirred for 18 h at rt
2. customThe reaction was quenched by the addition of 1 M NaOH (25 mL)
3. stirringwas stirred for 1 h
4. additionThe mixture was diluted with water
5. extractionextracted with DCM (3×60 mL)
6. washThe combined organic extracts were washed with H2O
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customto yield dark brown crude oil (6.2 g)
11. customThe crude product was purified on silica gel column