反应详情

To a solution of Cbz-His (1.00 g, 3.47 mmol) in DMF (15 mL) at 0° C. was added HOBT (0.64 g, 4.16 mmol) and DCC (0.86 g, 4.16 mmol). Tyr(OBn)-Ser(OBn)-CO2Me.TFA (from Step 2 above, 2.0 g, 3.47 mmol) was added followed by Et3N (0.58 mL, 4.16 mmol). The mixture was allowed to warm to room temperature and stirred overnight. The mixture was filtered and the filtrate was diluted with CHCl3, washed twice with saturated aqueous NaHCO3, brine, dried over MgSO4, and concentrated. Flash chromatography (2-5% MeOH/CHCl3) gave 2.14 g of the title compound as a white solid, mp 175°-176°C.; FAB-MS 734 (m+1);

1. filtrationThe mixture was filtered
2. additionthe filtrate was diluted with CHCl3
3. washwashed twice with saturated aqueous NaHCO3, brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated