反应详情

The dipeptide 1b from Step A (1.19 g, 3.38 mmol) was dissolved in HCl in dioxane (4.0 M, 13 mL, 51 mmol) and stirred at rt for 90 min to remove the Boc protective group. It was then concentrated down, taken up in acetonitrile and concentrated down again twice. This light brownish residue, 2(S)-tert-butoxycarbonylamino-non-8-enoic acid (0.95 g, 3.3 mmol) and HATU (1.4 g, 3.6 mmol) were dissolved in acetonitrile and cooled to 0° C. DIEA in acetonitrile was added drop-wise. The resulted mixture was allowed to warm to room temperature and stirred at room temperature for 10 h. The resulted mixture was concentrated, mixed with EtOAc, washed with aqueous saturated sodium bicarbonate, dried with Na2SO4, and concentrated. The residue was purified by silica gel chromatography (10% EtOAc and then 30% EtOAc) to give product 1d as pale yellowish oil (1.5 g, 90%). MS (ESI+): 528 [M+23] (5) and 406 [M+1−100] (100).

1. customto remove the Boc protective group
2. concentrationIt was then concentrated down
3. concentrationconcentrated down again twice
4. temperaturecooled to 0° C
5. temperatureto warm to room temperature
6. stirringstirred at room temperature for 10 h
7. concentrationThe resulted mixture was concentrated
8. additionmixed with EtOAc
9. washwashed with aqueous saturated sodium bicarbonate
10. dry with materialdried with Na2SO4
11. concentrationconcentrated
12. customThe residue was purified by silica gel chromatography (10% EtOAc