1: 95 percent / 1.5 N HCl/AcOH / 1 h 2: 90 percent / HOBt*H2O, NEt3, DCC / dimethylformamide / a) -5 deg C to 0 deg C, 1 h, b) 20 deg C, 24 h 3: 86 percent / 0.5 M NaOH / acetone / 1.5 h 4: 90 percent / 1.3 M HCl/AcOH / 1 h View Scheme

1: 95 percent / 1.5 N HCl/AcOH / 1 h 2: 90 percent / HOBt*H2O, NEt3, DCC / dimethylformamide / a) -5 deg C to 0 deg C, 1 h, b) 20 deg C, 24 h 3: 86 percent / 0.5 M NaOH / acetone / 1.5 h View Scheme

1: 91 percent / aq. NaOH / dioxane 2: acid hydrolysis View Scheme