hydrogen; acetic acid; palladium on activated charcoal in methanol; water 3 h;

1.1: diisopropylethylamine / ethanol / 18 h / Heating 1.2: 58 percent / NH3 / methanol / 0 - 20 °C 2.1: 100 percent / H2; acetic acid / Pd/C / methanol; H2O / 3 h View Scheme

1.1: 80 percent / pyridne / 12 h / 50 °C 2.1: 85 percent / N,N-dimethylaniline; phosphorus oxychloride / 0.22 h / Heating 3.1: diisopropylethylamine / ethanol / 18 h / Heating 3.2: 58 percent / NH3 / methanol / 0 - 20 °C 4.1: 100 percent / H2; acetic acid / Pd/C / methanol; H2O / 3 h View Scheme

1.1: 85 percent / N,N-dimethylaniline; phosphorus oxychloride / 0.22 h / Heating 2.1: diisopropylethylamine / ethanol / 18 h / Heating 2.2: 58 percent / NH3 / methanol / 0 - 20 °C 3.1: 100 percent / H2; acetic acid / Pd/C / methanol; H2O / 3 h View Scheme

1: 1,4-diaminobutane With trityl chloride resin; triethylamine in dichloromethane T=20°C; Substitution; 18 h; 2: 6-chloro-9-(β-D-ribofuranosyl)-purine With triethylamine in ethanol; dichloromethane T=60°C; Substitution; 18 h; 3: With C4H5F5O in dichloromethane T=20°C; Substitution; 0.25 h; Further stages.;