1-[2-(2-Aminoethoxy)ethyl]-2-(2-methoxyethyl)-6,7,8,9-tetrahydro-1H-imidazo[4,5-c]quinolin-4-amine (919 mg, 2.76 mmol) was dissolved in 30 mL of anhydrous CH2Cl2 and cooled to 0° C. under N2. The reaction mixture was then treated with phenyl isocyanate (300 μL, 2.76 mmol) and Et3N (0.77 mL, 5.51 mmol) and allowed to warm slowly to room temperature. After stirring overnight, the reaction mixture was then quenched by addition of saturated NaHCO3 solution (30 mL). The organic layer was separated and washed with H2O and brine, dried over Na2SO4 and concentrated under reduced pressure to give a yellow solid. The solid was triturated with Et2O (30 mL) and a few drops of MeOH. The solid was isolated by filtration and dried under vacuum to give 460 mg of N-(2-{2-[4-amino-2-(2-methoxyethyl)-6,7,8,9-tetrahydro-1H-imidazo[4,5-c]quinolin-1-yl]ethoxy}ethyl)-N′-phenylurea as a white powder. m.p. 180-182° C.; MS 453 (M+H)+;1H NMR (300 MHz, DMSO-d6) δ 8.51 (s, 1H); 7.37 (d, J=7.7 Hz, 2H); 7.19 (t, J=8.2 Hz, 2H); 6.86 (t, J=7.7 Hz, 1H); 6.11 (t, J=5.5 Hz, 2H); 5.70 (s, 2H); 4.43 (t, J=5.1 Hz, 2H); 3.78-3.69 (m, 4H); 3.39 (t, J=5.6 Hz, 2H); 3.25 (s, 3H); 3.19 (m, 2H); 3.10 (t, J=6.8 Hz, 2H); 2.91 (m, 2H); 2.64 (m, 2H); 1.72 (m, 4H); 13C (75 MHz, DMSO-d6) δ 155.5, 151.3, 149.3, 146.3, 140.8, 138.5, 129.0, 125.0, 121.4, 118.0, 105.6, 70.6, 70.5, 70.4, 58.4, 44.6, 39.2, 32.7, 27.6, 23.8, 23.1, 23.0; Anal. Calcd for C24H32N6O3: % C, 63.70, % H, 7.13, % N, 18.57. Found: % C, 63.33, % H, 7.16, % N, 18.66.
