3-Benzyl-2-(1-{[2-(dimethylamino)ethyl]amino}propyl)thieno[3,2-d]pyrimidin-4(3H)-one (1-7, 0.030 g, 0.081 mmol) was dissolved in DCE (1.0 mL) and treated successively with 4-bromo-benzoylchloride (0.026 g, 0.12 mmol) and TEA (0.03 mL, 0.24 mmol). The reaction was stirred at 25° C. for 1 h. The reaction was diluted with DCM (10 mL), washed with 5% NaHCO3 and dried over MgSO4. The organics were concentrated under reduced pressure and subjected to flash column chromatography (SiO2, 0-6% MeOH/CH2Cl2 gradient) to provide N-[1-(3-benzyl-4-oxo-3,4-dihydrothieno[3,2-d]pyrimidin-2-yl)propyl]-4-bromo-N-[2-(dimethylamino)ethyl]benzamide (1-8). 1H NMR (300 MHz, CDCl3) δ 7.83 (d, J=5.2 Hz, 1H), 7.54 (m, 2H), 7.32 (m, 5H), 7.15 (m, 2H), 6.11 (d, J=16.0 Hz, 1H), 5.96 (t, J=7.0 Hz, 1H), 5.12 (d, J=16.0 Hz, 1H), 3.40 (m, 2H), 2.04 (m, 2H), 1.85 (m, 1H), 1.77 (s, 6H), 1.59 (m, 1H), 0.65 (t, J=6.9 Hz, 3H); MS 553.1 found, 553.5 required.
