反应详情

To a solution of the crude compound obtained in step 4 (0.420 g, 0.69 mmol), 1-tert-butoxycarbonyl-piperazine (0.142 g, 0.76 mmol) and triethylamine (0.48 ml, 2.78 mmol) in 3.5 ml of DMF cooled at 0° C., was added TBTU (0.490 g, 1.53 mmol) in small portions, and the mixture was stirred at room temperature overnight. 10 ml of EA and 20 ml of brine were then added, the aqueous phase was separated and extracted twice with EA. The combined organic phases were washed with water, 1 N hydrochloric acid, water, an saturated solution of sodium hydrogencarbonate and brine, dried over sodium sulfate, filtered and evaporated to dryness under reduced pressure. The residue was purified by chromatography on silica gel (cyclohexane/EA, 100:0, then 70:30) to give 0.162 g of the title compound as a beige solid.

1. customthe aqueous phase was separated
2. extractionextracted twice with EA
3. washThe combined organic phases were washed with water, 1 N hydrochloric acid, water
4. dry with materialan saturated solution of sodium hydrogencarbonate and brine, dried over sodium sulfate
5. filtrationfiltered
6. customevaporated to dryness under reduced pressure
7. customThe residue was purified by chromatography on silica gel (cyclohexane/EA, 100:0