1: pyridine 2: 10 percent / trimethyl orthoformate, O2, toluene-p-sulphonic acid / dioxane 3: 39.8 percent / ethanol / 2.5 h / Irradiation 4: 75 percent / H2 / Pd-CaCO3 / pyridine 5: 28.5 mg / potassium hydrogen carbonate, H2O / ethanol / 1 h / Heating 6: 28 mg / HCl / 18 h / Ambient temperature 7: POCl3-pyridine 8: 60percent acetic acid / 91 h / Ambient temperature 9: 1 mg / H2 / Pd-C / dioxane / 6 h View Scheme