1: NaH / tetrahydrofuran / Ambient temperature 2: camphorsulfonic acid / CH2Cl2 / 0 °C 3: DMSO, (COCl)2, Et3N / CH2Cl2 4: 28 percent / (Ph3P)3RhCl / acetonitrile / 160 °C 5: DDQ / CH2Cl2; H2O 6: DMSO, (COCl)2 / CH2Cl2 7: TsOH / benzene 8: H2 / Pd-C / ethyl acetate 9: CrO3, H2SO4 / acetone 10: 2N-HCl / tetrahydrofuran / Ambient temperature 11: (C6H11)2NMgBr / methanol / -55 °C 12: DDQ / CH2Cl2 / 1.5 h / Ambient temperature; buffer (pH 6.86) View Scheme