1: 92 percent / 1 M aq. NaOH / ethanol / 18 h / Ambient temperature 2: (COCl)2, DMF / toluene / 1 h 3: CBrCl3, 2-mercaptopyridine N-oxide sodium salt, 4-(dimethylamino)pyridine / 1 h / 80 °C / Irradiation 4: aq. AcOH, conc. HCl / 3 h / Ambient temperature 5: 92 percent / KOH / methanol / 3 h / Ambient temperature 6: 86 percent / propan-2-ol / 6 h / 80 °C 7: 100 percent / H2 / 10percent Pd/C / ethanol / 24 h View Scheme

1: 92 percent / 1 M aq. NaOH / ethanol / 18 h / Ambient temperature 2: (COCl)2, DMF / toluene / 1 h 3: CBrCl3, 2-mercaptopyridine N-oxide sodium salt, 4-(dimethylamino)pyridine / 1 h / 80 °C / Irradiation 4: aq. AcOH, conc. HCl / 3 h / Ambient temperature 5: 92 percent / KOH / methanol / 3 h / Ambient temperature 6: 86 percent / propan-2-ol / 6 h / 80 °C 7: 100 percent / H2 / 10percent Pd/C / ethanol / 24 h 8: 48 percent / 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 64 h / Ambient temperature 9: H2 / 10percent Pd/C / ethanol / 16 h 10: 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 16 h / Ambient temperature View Scheme

1: 92 percent / 1 M aq. NaOH / ethanol / 18 h / Ambient temperature 2: (COCl)2, DMF / toluene / 1 h 3: CBrCl3, 2-mercaptopyridine N-oxide sodium salt, 4-(dimethylamino)pyridine / 1 h / 80 °C / Irradiation 4: aq. AcOH, conc. HCl / 3 h / Ambient temperature 5: 92 percent / KOH / methanol / 3 h / Ambient temperature 6: 86 percent / propan-2-ol / 6 h / 80 °C 7: 100 percent / H2 / 10percent Pd/C / ethanol / 24 h 8: 48 percent / 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 64 h / Ambient temperature View Scheme