Reaction Steps
WSC hydrochloride (52.5 mg, 0.274 mmol) was added to a mixture of 3-(1H-indol-5-yl)-5-methoxybenzoic acid (61.0 mg, 0.228 mmol), 6-(tetrazol-5-yl)spiro[chroman-2,4′-piperidin]-4-one hydrochloride (73.4 mg, 0.228 mmol), HOBT (34.9 mg, 0.228 mmol), triethylamine (0.048 mL, 0.34 mmol), chloroform (0.4 mL) and NMP (0.8 mL), and stirred at room temperature for 20 hours. The reaction mixture was concentrated under reduced pressure, and the residue was purified through high-performance preparative liquid chromatography (0.1% TFA, water/acetonitrile) to obtain the title compound as a pale yellow solid. 1H-NMR (400 MHz, DMSO-d6) δ: 11.18 (1H, s), 8.43 (1H, d J=2.3 Hz), 8.25 (1H, dd, J=8.8, 2.3 Hz), 7.87-7.86 (1H, m), 7.47 (1H, d, J=8.4 Hz), 7.41 (1H, dd, J=8.4, 1.7 Hz), 7.39 (1H, t, J=2.8 Hz), 7.35 (1H, d, J=8.8 Hz), 7.26 (1H, dd, J=2.4, 1.5 Hz), 7.24 (1H, t, J=1.5 Hz), 6.87 (1H, dd, J=2.4, 1.5 Hz), 6.49 (1H, ddd, J=2.8, 2.1, 0.7 Hz), 4.37-4.23 (1H, m), 3.86 (3H, s), 3.66-3.18 (3H, m), 2.99 (2.0H, s), 2.14-1.81 (4H, m). MS [M−H]−=533.
