Reaction Steps
A mixture of 3-(5-acetyl-1H-indol-2-yl)-2(1H)-quinolinone (8-4, 50.0 mg, 0.165 mmol, 1 equiv), morpholine (0.070 mL, 0.83 mmol, 5.0 equiv), acetic acid (0.050 mL, 0.83 mmol, 5.0 equiv), sodium cyanoborohydride (52 mg, 0.83 mmol, 5.0 equiv), and activated powdered 3 angstrom molecular sieves in anhydrous 20% dioxane in methanol (15 mL) was heated at 50° C. for 8 h. Additional morpholine (0.070 mL, 0.83 mmol, 5.0 equiv), acetic acid (0.050 mL, 0.83 mmol, 5.0 equiv), and sodium cyanoborohydride (52 mg, 0.83 mmol, 5.0 equiv) was added, and this was repeated (3×) every 8-12 hours over the course of two days. The reaction mixture was partitioned between a 1:1 mixture of saturated sodium carbonate solution and brine and ethyl acetate (100 mL). The organic layer was dried over sodium sulfate and concentrated. The residue was purified by reverse-phase liquid chromatography (H2O/CH3CN gradient w/0.1% TFA present) to provide 3-{5-[1-(4-morpholinyl)ethyl]-1H-indol-2-yl}-2(1H)-quinolinone (8-5) as a yellow solid. 1H NMR (500 MHz, CDCl3) δ 11.15 (s, 1H), 9.28 (br s, 1H), 8.37 (s, 1H), 7.72 (d, 1H, J=8.0 Hz), 7.57 (s, 1H), 7.54 (br t, 1H, J=7.6 Hz), 7.43 (d, 1H, J=8.0 Hz), 7.32 (t, 1H, J=7.6 Hz), 7.27 (d, 1H, J=7.8 Hz), 7.22 (d, 1H, J=7.9 Hz), 7.04 (s, 1H), 3.72 (m, 4H), 3.41 (q, 1H, J=6.6 Hz), 2.56 (m, 2H), 2.43 (m, 2H), 1.46 (d, 3H, J=6.6 Hz).
