1: 1.) isobutyl chloroformate, triethylamine, 2.) triethylamine / 1.) DMF, 0-5 deg C, 1.5 h, 2.) DMF, RT, 24 h 2: aq. NaOH / 2-methoxy-ethanol / Ambient temperature View Scheme

sodium hydroxide in dimethyl sulfoxide T=20 - 25°C; 29 h;

1.1: H2; gl. AcOH / PtO2 / 18 h 1.2: 3percent H2O2 / 20 h 2.1: 5 N NaOH / dimethylsulfoxide / 0.17 h / 20 °C View Scheme

methanol; potassium permanganate in acetonitrile T=25°C; 0.5 h;

1: 4 h / Heating 2: 1N HCl / trifluoroacetic acid / 0.33 h / 60 - 65 °C 3: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 4: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 5: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme

1: 65 percent / tetrahydrofuran; acetone / 1.) -15 deg C, 3h, 2.) 25 deg C, 18h 2: 100 percent / pyridine, hydroxylamine hydrochloride / methanol / 1 h / Heating 3: 95percent hydrazine hydrate / methanol / 72 h / Heating 4: 4 h / Heating 5: 1N HCl / trifluoroacetic acid / 0.33 h / 60 - 65 °C 6: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 7: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 8: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme

1: 100 percent / pyridine, hydroxylamine hydrochloride / methanol / 1 h / Heating 2: 95percent hydrazine hydrate / methanol / 72 h / Heating 3: 4 h / Heating 4: 1N HCl / trifluoroacetic acid / 0.33 h / 60 - 65 °C 5: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 6: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 7: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme

1: 95percent hydrazine hydrate / methanol / 72 h / Heating 2: 4 h / Heating 3: 1N HCl / trifluoroacetic acid / 0.33 h / 60 - 65 °C 4: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 5: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 6: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme

1: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 2: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 3: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme

1: 1N HCl / trifluoroacetic acid / 0.33 h / 60 - 65 °C 2: sodium dithionite / dimethylformamide; H2O / 2 h / 60 - 65 °C 3: 0.1 N NaOH / acetonitrile / 18 h / 25 °C 4: MeOH, 5percent KMnO4 / acetonitrile / 0.5 h / 25 °C View Scheme