Reaction Steps
2-{4-[(R)-3-(2,4-Dimethyl-phenoxy)-2-hydroxy-propylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-6-(1-methyl-piperidin-4-yl)-1H-1,3,6-triaza-s-indacene-5,7-dione (3.0 g, 5.26 mmol) was mixed with zinc dust (6.88 g, 10.52 mmol) in AcOH (150 mL). After it was heated at 90° C. for 2 h, the reaction mixture was filtered and the filtrate was evaporated at 95° C. (the bath temperature) under reduced pressure to dryness. The residue was basified with 28% aqueous NH4OH solution and concentrated. Chromatography of the residual crude with CH2Cl2/MeOH/28% aqueous NH4OH (90:10:1) afforded the title compound (2.45 g, 84%). 1H NMR (DMSO-d6) δ 1.70 (m, 2H), 1.80 (m, 2H), 2.05 (m, 2H), 2.20 (s, 3H, CH3), 2.22 (s, 3H, CH3), 2.28 (s, 3H, CH3), 2.89 (m, 2H), 3.57 (m, 1H), 3.79 (m, 1H), 3.95-4.09 (3H), 4.11 (m, 1H), 4.40 (s, 1H), 4.45 (s, 1H), 5.47 (d, J=3 Hz, 0.5H, NH), 5.54 (d, J=3 Hz, 0.5H, NH), 6.21 (m, 1H), 6.80-7.00 (3H), 7.30-7.39 (1.5H), 7.69 (s, 0.5H), 7.79 (s, 0.5H), 7.93 (s, 0.5H), 11.12 (br d, J=6 Hz, 1H, NH), 11.22 (br d, J=6 Hz, 1H, NH); ESI-MS m/z 557.7 (MH+).
