1: 243.3 g / aq. hydrazine hydrate / tetrahydrofuran; methanol / 10 - 20 °C 2: 72.2 percent / acetic acid / 5 - 20 °C 3: 87.3 percent / dimethylformamide; H2O / 6 h / Heating 4: 94.1 percent / aq. potassium hydroxide / methanol / 16 h / Heating 5: 73.5 percent / N,N'-dicyclohexylcarbodiimide; N,N-dimethylaminopyridine / CH2Cl2 / 2 h View Scheme

1: 243.3 g / aq. hydrazine hydrate / tetrahydrofuran; methanol / 10 - 20 °C 2: 72.2 percent / acetic acid / 5 - 20 °C 3: 87.3 percent / dimethylformamide; H2O / 6 h / Heating 4: 94.1 percent / aq. potassium hydroxide / methanol / 16 h / Heating 5: 74.4 percent / N,N'-dicyclohexylcarbodiimide; N,N-dimethylaminopyridine / CH2Cl2 / 4 h View Scheme

1: 243.3 g / aq. hydrazine hydrate / tetrahydrofuran; methanol / 10 - 20 °C 2: 72.2 percent / acetic acid / 5 - 20 °C 3: 87.3 percent / dimethylformamide; H2O / 6 h / Heating View Scheme

1: 243.3 g / aq. hydrazine hydrate / tetrahydrofuran; methanol / 10 - 20 °C 2: 72.2 percent / acetic acid / 5 - 20 °C 3: 87.3 percent / dimethylformamide; H2O / 6 h / Heating 4: 94.1 percent / aq. potassium hydroxide / methanol / 16 h / Heating View Scheme

acetic acid; zinc in methanol; dichloromethane Heating;