in ethanol 2 h; Heating;

1: ethanol / 0.25 h / Heating 2: pyridine 3: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 4: 66.5 percent / pyridine 5: 100 percent / ethanol / 2 h / Heating View Scheme

1: urea / 0.33 h / 150 - 160 °C 2: ethanol / 0.25 h / Heating 3: pyridine 4: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 5: 66.5 percent / pyridine 6: 100 percent / ethanol / 2 h / Heating View Scheme

1: acetic anhydride / 0.08 h / Heating 2: urea / 0.33 h / 150 - 160 °C 3: ethanol / 0.25 h / Heating 4: pyridine 5: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 6: 66.5 percent / pyridine 7: 100 percent / ethanol / 2 h / Heating View Scheme

1: pyridine 2: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 3: 66.5 percent / pyridine 4: 100 percent / ethanol / 2 h / Heating View Scheme

1: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 2: 66.5 percent / pyridine 3: 100 percent / ethanol / 2 h / Heating View Scheme

1: 75.7 percent / 15 h / 115 °C 2: 66.5 percent / pyridine 3: 100 percent / ethanol / 2 h / Heating View Scheme

1: 66.5 percent / pyridine 2: 100 percent / ethanol / 2 h / Heating View Scheme

1: 49.3 percent / 1percent HCl / 1 h / Heating 2: 75.7 percent / 15 h / 115 °C 3: 66.5 percent / pyridine 4: 100 percent / ethanol / 2 h / Heating View Scheme