反应详情

1500 mg of the compound from Example 10A (4.28 mol) are dissolved in 30 ml of dimethylformamide, and 2788 mg of caesium carbonate (8.56 mol) are added. 0.95 ml of ethyl bromoacetate (1429 mg, 8.56 mol) is added drop wise, and the suspension is stirred at room temperature overnight. Water is added, and the mixture is extracted three times with dichloromethane. The combined organic phases are dried over sodium sulphate and concentrated in a rotary evaporator. The residue is purified by preparative HPLC (eluent: acetonitrile/water with 0.1% formic acid, gradient 20:80→95:5). 450 mg (24% of theory) of the title compound are obtained.

1. extractionthe mixture is extracted three times with dichloromethane
2. dry with materialThe combined organic phases are dried over sodium sulphate
3. concentrationconcentrated in a rotary evaporator
4. customThe residue is purified by preparative HPLC (eluent: acetonitrile/water with 0.1% formic acid, gradient 20:80→95:5)