Reaction Steps
Part E: To a solution of 4-(pyridin-2-yl)-5,6,7,8-tetrahydropyrido[3,4-d]pyrimidine hydrochloride (0.137 g, 0.55 mmol) in DMF (15 mL) at 25° C. was added sequentially 2-(4-methoxy-7-(3-methyl-1H-1,2,4-triazol-1-yl)-1H-pyrrolo[2,3-c]pyridin-3-yl)-2-oxoacetic acid (0.151 g, 0.50 mmol), N-methylmorpholine (0.220 mL, 2.00 mmol), and TBTU (0.177 g, 0.55 mmol), and the mixture was stirred at 25° C. for 18 h. The reaction mixture was concentrated under vacuum, and the residue dissolved in hot methanol. The solution was allowed to cool slowly to room temperature. The precipitate was recovered by filtration, washed with methanol, and dried under vacuum to provide 1-(4-methoxy-7-(3-methyl-1H-1,2,4-triazol-1-yl)-1H-pyrrolo[2,3-c]pyridin-3-yl)-2-(4-(pyridin-2-yl)-5,6-dihydropyrido[3,4-d]pyrimidin-7(8H)-yl)ethane-1,2-dione (0.122 g, 49%) as an off-white solid; HRMS: 496.1835 (M+H)+ [calc'd: 496.1840]; 1H NMR (500 MHz, DMSO-d6) δ 12.44 (br s, 1H), 9.24 (m, 1H), 9.17 (s, 2/3H), 9.08 (s, 1/3H), 8.77 (m, 1/3H), 8.67 (m, 2/3H), 8.34 (s, 2/3H), 8.26 (s, 1/3H), 8.12-8.00 (m, 2H), 7.87 (m, 1H), 7.58 (m, 1/3H), 7.53 (m, 2/3H), 4.92 (s, 4/3H), 4.72 (s, 2/3H), 3.93 (m, 1/3H), 3.91 (s, 1H), 3.85 (s, 2H), 3.70 (m, 2/3H), 3.32 (m, 1/3H), 3.18 (m, 2/3H), 2.50 (s, 2H), 2.49 (s, 1H).