1: 1.) MsCl, pyridine, 2.) LAH / 1. 25 gradC, 17 h.; 2. DME, 0 gradC to 25 gradC, 17 h. 2: 96 percent / KH / tetrahydrofuran / 1.5 h / 25 °C 3: 1.) HF/H2O, 2.) Jones reagent / 1. CH3CN, THF, 25 gradC, 3 h; 2. CH3COCH3, 0 gradC to 25 gradC, 15 min. 4: 1. I2, 2,4,6-collidine, CH3CN, 25 gradC, 35 min; 2. Bu3SnH, AIBN, PhH, 80 gradC, 6 h. 5: 92 percent / NaBH4 / methanol / -78 - 25 °C 6: 82 percent / H2 / 10percent Pd/C, 70percent HClO4 / methanol / 25 °C / 2068.6 Torr 7: 2.) DIBAL / 1. 90 gradC, 50 h; 2. THF, 0 gradC, 1 h. View Scheme

Multi-step reaction with 12 steps 1: 1.) Mg / 2.) THF, 0deg C, 1.5 h2: 97 percent / DMAP, Et3N / dimethylformamide / 10 h / 25 °C3: pentane / 25 °C / Irradiation4: 71 percent / Hg(OAc)2 / tetrahydrofuran; H2O / 0.25 h / 25 °C5: 94 percent / NaBH4 / methanol / 0.25 h / 25 °C6: 93 percent / MnO2 / CH2Cl2 / 24 h / 25 °C7: 99 percent / H2 / 5percent Pd/C / diethyl ether / 11 h / 25 °C / 760 Torr8: 95 percent / DMAP, Et3N / dimethylformamide / 36 h / 46 - 50 °C10: 72 percent / NaBH4, CeCl3 / methanol / 3 h / -78 °C11: 1.) O3, 2.) NaBH4 / 1. MeOH, CH2Cl2, -78 gradC; 2. -78 gradC to 25 gradC12: 97 percent / imidazole / dimethylformamide / 5 h / 25 °C  

Multi-step reaction with 10 steps 1: pentane / 25 °C / Irradiation2: 71 percent / Hg(OAc)2 / tetrahydrofuran; H2O / 0.25 h / 25 °C3: 94 percent / NaBH4 / methanol / 0.25 h / 25 °C4: 93 percent / MnO2 / CH2Cl2 / 24 h / 25 °C5: 99 percent / H2 / 5percent Pd/C / diethyl ether / 11 h / 25 °C / 760 Torr6: 95 percent / DMAP, Et3N / dimethylformamide / 36 h / 46 - 50 °C8: 72 percent / NaBH4, CeCl3 / methanol / 3 h / -78 °C9: 1.) O3, 2.) NaBH4 / 1. MeOH, CH2Cl2, -78 gradC; 2. -78 gradC to 25 gradC10: 97 percent / imidazole / dimethylformamide / 5 h / 25 °C