1: 1.) O3, 2.) NaBH4 / 1.) CH2Cl2, -78 deg C 2: Et3N / 0 °C 3: 1N-HCl / tetrahydrofuran / Ambient temperature 4: K2CO3 / methanol 5: NaH / tetrahydrofuran / Ambient temperature 6: camphorsulfonic acid / CH2Cl2 / 0 °C 7: DMSO, (COCl)2, Et3N / CH2Cl2 8: 28 percent / (Ph3P)3RhCl / acetonitrile / 160 °C 9: DDQ / CH2Cl2; H2O 10: DMSO, (COCl)2 / CH2Cl2 11: TsOH / benzene 12: H2 / Pd-C / ethyl acetate 13: CrO3, H2SO4 / acetone 14: 2N-HCl / tetrahydrofuran / Ambient temperature 15: (C6H11)2NMgBr / methanol / -55 °C 16: DDQ / CH2Cl2 / 1.5 h / Ambient temperature; buffer (pH 6.86) View Scheme

Multi-step reaction with 4 steps 1: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -70 deg C, 30 min, 2) CH2Cl2, -70 to 0 deg C2: 1) NaH / 1) DMF, 45 min, 0 deg C, 2) DMF, THF, 0 to 20 deg C3: 94 percent / hydrogen / 10percent Pd/C / ethyl acetate4: 97 percent / tetrahydrofuran / 3 h / -40 °C  

Multi-step reaction with 7 steps 1: LiAlH4 / tetrahydrofuran / 0.5 h / 0 °C2: CSA / acetone / 0.5 h / Ambient temperature3: 96 percent / hydrogen / 10percent Pd/C / ethanol / 3.5 h / Ambient temperature4: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -70 deg C, 30 min, 2) CH2Cl2, -70 to 0 deg C5: 1) NaH / 1) DMF, 45 min, 0 deg C, 2) DMF, THF, 0 to 20 deg C6: 94 percent / hydrogen / 10percent Pd/C / ethyl acetate7: 97 percent / tetrahydrofuran / 3 h / -40 °C