Reaction Steps
A mixture of 2-aminoimidazole sulfate (0.100 g, 0.757 mmol), 1,1′-carbonyldiimidazole (0.129 g, 0.796 mmol) and DIPEA (0.293 g, 2.27 mmol) in CH2Cl2 (10 mL) was stirred for 5 h, and then the solvent was removed. The residue was dissolved in DMF (6 mL), and 4-((2′S,6′R)-3,3″-dimethyl-3′,4′,5′,6′-tetrahydro-2′H-[2,2′;6′,2″]terpyridin-1′-yl)-butylamine (0.130 g, 0.384 mmol) and DIPEA (0.293 g, 2.27 mmol) were added. The mixture was heated at 75° C. for 16 h, and then cooled to room temperature. Saturated aqueous NaHCO3 (20 mL) was added, and the mixture was extracted with CH2Cl2 (3×30 mL). The extracts were combined and dried over Na2SO4. After filtration the solvent was removed by evaporation under vacuum, and the residue was purified by flash chromatography on a silica gel column (100:5:2 CH2Cl2/CH3OH/NH4OH), affording a pale yellow solid (0.115 g, 67%) after precipitation from CH2Cl2/hexanes by evaporation under vacuum. 1H NMR(CDCl3) δ 0.70-0.85 (m, 4H), 1.46-1.66 (m, 3H), 1.90-2.00 (m, 2H), 2.15-2.19 (m, 2H), 2.41 (s, 6H), 2.53-2.70 (m, 1H), 2.75-2.83 (m, 2H), 3.95-4.00 (m, 2H), 6.69 (s, 2H), 6.90-7.02 (m, 2H), 7.30-7.40 (m, 2H), 8.34-8.42 (m, 2H); 13C NMR(CDCl3) δ 18.96, 22.82, 25.22, 27.67, 31.30, 39.41, 50.56, 63.61, 122.03, 131.12, 138.63, 144.22, 146.85, 155.71, 160.40. ES-MS m/z 448 (M+H). Anal. Calcd. for C25H33N7O.0.1CH2Cl2.0.1C6H14: C, 66.43; H, 7.50; N, 21.10. Found: C, 66.41; H, 7.46; N, 20.87.
