hydrogen bromide; dimethyl sulfoxide T=55°C; 24 h;

water 3 h; Heating;

hydrogenchloride; acetone-oxime in water T=50°C; 2 h; pH 4;

in 1,4-dioxane RefluxInert atmosphere;

iodine in dimethyl sulfoxide T=100°C;

1: 92 percent / acetonoxime, 2 N HCl / H2O / 2 h / 50 °C / pH 4 2: 76 percent / methanol / 120 h 3: 96 percent / NH3(g) / propan-1-ol / 36 h / Ambient temperature 4: 86 percent / Na2S2O4 / H2O / 24 h / Heating 5: 67 percent / dimethylformamide / 12 h / 160 °C 6: 45 percent / 1) 90percent aq. Na2S2O4, 0.5M NaOH, 15 min, reflux; 2) O.1M NaOH, O.1M KMnO4, r.t., 10 min 7: 87 percent / xanthine oxidase (AXO) / 120 h / 4N NaOH, potassium phosphate buffer, pH 8.0 View Scheme

1: 92 percent / acetonoxime, 2 N HCl / H2O / 2 h / 50 °C / pH 4 2: 76 percent / methanol / 120 h 3: 96 percent / NH3(g) / propan-1-ol / 36 h / Ambient temperature 4: 86 percent / Na2S2O4 / H2O / 24 h / Heating 5: 84 percent / acetic anhydride / 2 h / Heating 6: 86 percent / xanthine oxidase (AXO) / 120 h / 4N NaOH, potassium phosphate buffer, pH 8.0 View Scheme