Reaction Steps
To a suspension of 343 (106 mg, 0.20 mmol, scheme 71) in THF (3 mL) was added ethoxycarbonylmethyl isocyanate (0.068 mL, 0.6 mmol) and stirred at RT for 3 h. To the mixture was added DMF (2 mL) and stirred for 1 h. The mixture was then concentrated, water was added to form a precipitate that was collected by filtration, rinsed with water and purified via Biotage [linear gradient 2-20%, (methanol/dichloromethane; SiliaFlash 10 g cartridge]. Title compound 425 was obtained as a white solid (79.5 mg, 60% yield). 1H NMR (400 MHz, DMSO-d6) δ (ppm): 8.73 (s, 1H), 8.54 (brd, 1H), 8.52 (d, J=5.6 Hz, 1H), 8.33 (s, 1H), 8.24 (d, J=8.0 Hz, 1H), 7.85 (dd, J=8.0, 2.0 Hz, 1H), 7.73 (dd, J=13.6, 2.4 Hz, 1H), 7.38 (t, J=9.0 Hz, 1H), 7.23-7.18 (m, 1H), 6.64 (d, J=5.2 Hz, 1H), 6.59 (bd, 1H), 6.15 (d, J=8.0 Hz, 1H), 6.06 (t, J=8.0 Hz, 1H), 4.06 (q, J=6.4 Hz, 2H), 3.74 (d, J=6.50 Hz, 2H), 3.54 (s, 2H), 2.77-2.66 (m, 2H), 2.58-2.51 (m, 2H), 2.13-2.04 (m, 2H), 1.78-1.70 (m, 2H), 1.40-1.30 (m, 2H), 1.18 (t, J=6.8 Hz, 3H), 0.68-0.62 (m, 2H), 0.45-0.40 (m, 2H). MS (m/z): 662.28 (M+H).
