General procedure for the synthesis of α-amino-1H-indole-5-acetic acid from the compound (CAS: 108763-42-4): (f) DL-α-amino-α-(indol-5-yl)acetic acid (6f, 17.3 g, 0.08 mol) was mixed with barium hydroxide (92.12 g, 0.292 mol) in 560 mL of water and stirred at 100°C for The reaction was carried out for 24 h. The reaction process was similar to Example 1d. Upon completion of the reaction, the product α-amino-1H-indole-5-acetic acid was obtained in a yield of 12.1 g (67% yield); the molecular formula was C10H10N2O2-2H2O (molecular weight 226.2). Nuclear magnetic resonance hydrogen spectroscopy (NaOD) data: δ= 4.43 (s, 1H), 6.57 (d, 1H), 7.22 (d, 1H), 7.39 (d, 1H), 7.5 (d, 1H), 7.65 (s, 1H) ppm.
