反应详情

The compound (67 mg, 0.097 mmol) obtained in Example 1j was dissolved in methylene chloride (2 mL), triethylamine (18 μL, 0.13 mmol) and pivaloyl chloride (12 μL, 0.097 mmol) were added under ice cooling, and the mixture was stirred at room temperature for 15 minutes. A solution of the compound (59 mg, 0.088 mmol) obtained in Example 11d in methylene chloride (2 mL) was added dropwise under ice cooling, and the mixture was stirred at room temperature for 2 hours. The solvent was evaporated under reduced pressure, and the resulting residue was purified by NH silica gel column chromatography (ethyl acetate:methanol=40:1→20:1, v/v) and further purified by reverse phase preparative column chromatography (Waters; XTerra Prep MS C18 OBD, 5 μm, 30×100 mm) (acetonitrile:0.1% aqueous ammonium formate solution=50:50→60:40, v/v) to give the title compound (53 mg; yield, 41%) as a light yellow solid.

1. stirringthe mixture was stirred at room temperature for 2 hours
2. customThe solvent was evaporated under reduced pressure
3. customthe resulting residue was purified by NH silica gel column chromatography (ethyl acetate:methanol=40:1→20:1, v/v)
4. customfurther purified by reverse phase preparative column chromatography (Waters; XTerra Prep MS C18 OBD, 5 μm, 30×100 mm) (acetonitrile