1: LiOH; H2O / 12 h / 25 °C 2: PhSO2Cl; pyridine / 8 h / 0 °C 3: 90 percent / PPTS / ethanol / 3 h / Heating 4: 95 percent / DCC; DMAP 5: H2 / 10 percent Pd/C / 12 h 6: 87 percent / tetrahydrofuran / 1 h / 23 °C View Scheme

1: LiOH; H2O / 12 h / 25 °C 2: PhSO2Cl; pyridine / 8 h / 0 °C 3: 90 percent / PPTS / ethanol / 3 h / Heating 4: 95 percent / DCC; DMAP View Scheme