Multi-step reaction with 11 steps 1: pyridine / tetrahydrofuran / 18 h / 22 °C2: 84 percent / lead tetraacetate / benzene / 8 h / 22 °C3: CH2Cl2 / 10 h / 23 °C4: 10percent aq. hydrochloric acid / tetrahydrofuran / 20 h / 23 °C5: 99 percent / conc. sulfuric acid, N-bromosuccinimide / tetrahydrofuran / 1 h / -23 °C6: 1.) sodium hydride / dimethylformamide / 1.) 25 deg C, 30 min; 2.) 25 deg C, 1 h7: tri-n-butyltin hydride / AIBN / benzene / 4 h / Heating8: 1.) borane methyl sulfide 2.) 2 N aq. sodium hydroxide, 30percent aq. hydrogen peroxide / 1.) THF, 25 deg C, 3 h; 2.) THF, 45 deg C, 30 min9: 83 percent / acetyl chloride / methanol / 2 h / 50 °C10: sodium bis(2-methoxyethoxy)aluminum hydride / toluene / 3 h / 100 °C11: tetrahydrofuran / 20 h / 23 °C  

Multi-step reaction with 12 steps 1: 90 percent / Na2S2O4 / tetrahydrofuran; H2O / 30 h / Heating2: pyridine / tetrahydrofuran / 18 h / 22 °C3: 84 percent / lead tetraacetate / benzene / 8 h / 22 °C4: CH2Cl2 / 10 h / 23 °C5: 10percent aq. hydrochloric acid / tetrahydrofuran / 20 h / 23 °C6: 99 percent / conc. sulfuric acid, N-bromosuccinimide / tetrahydrofuran / 1 h / -23 °C7: 1.) sodium hydride / dimethylformamide / 1.) 25 deg C, 30 min; 2.) 25 deg C, 1 h8: tri-n-butyltin hydride / AIBN / benzene / 4 h / Heating9: 1.) borane methyl sulfide 2.) 2 N aq. sodium hydroxide, 30percent aq. hydrogen peroxide / 1.) THF, 25 deg C, 3 h; 2.) THF, 45 deg C, 30 min10: 83 percent / acetyl chloride / methanol / 2 h / 50 °C11: sodium bis(2-methoxyethoxy)aluminum hydride / toluene / 3 h / 100 °C12: tetrahydrofuran / 20 h / 23 °C  

Multi-step reaction with 4 steps 1: triphenylphosphine, carbon tetrachloride / CH2Cl2 / 14 h / 23 °C2: 100 percent / 25percent aq. ammonium formate / 10percent palladium/carbon / tetrahydrofuran / 0.5 h / 24 °C3: 3 N hydrochloric acid / ethyl acetate / 0.75 h / 21 °C4: 88 percent / sodium bicarbonate, EDCI / dimethylformamide / 17 h / 24 °C  

Multi-step reaction with 5 steps 1: pyridine / 6 h / Ambient temperature2: lithium chloride / dimethylformamide / 0.42 h / 80 °C3: ammonium formate / 10percent Pd/C / tetrahydrofuran; methanol / 0.33 h / Ambient temperature4: hydrogen chloride gas / ethyl acetate / 0.67 h5: 58 percent / EDC / N,N-dimethyl-acetamide / 3 h