反应详情

To a solution of 4-amino butyric acid (0.093 g, 0.90 mmol) in acetic acid (0.5 mL) at 55° C. was added paraformaldehyde (0.027 g, 0.90 mmol). After stirring for 10 min, 3-[(3,4-dichloro-benzyl)-methoxy-carbamoyl]-2-hydroxy-acrylic acid methyl ester (0.2978 g, 0.89 mmol) was added and the mixture was stirred at 55° C. for 1 h. The clear yellow solution was cooled, concentrated and purified by preparative HPLC (C18, ODS-A, S-75 μm, 10%–40% acetonitrile/water/0.5% HCl) to give the title compound as a yellow foam (0.129 g, 34% yield). HRMS (M+H) calcd for C17H19N2Cl2O6: 417.06203; found: 417.0607.

1. stirringthe mixture was stirred at 55° C. for 1 h
2. temperatureThe clear yellow solution was cooled
3. concentrationconcentrated
4. custompurified by preparative HPLC (C18, ODS-A, S-75 μm, 10%–40% acetonitrile/water/0.5% HCl)