¹H NMR (400 MHz, CDCl₃) δ 9.19 (s, 1H), 8.29 (s, 1H), 8.15 (d, J = 8.4 Hz, 1H), 7.87 (d, J = 8.1 Hz, 1H), 7.72 (t, J = 7.6 Hz, 1H), 7.57 (t, J = 7.5 Hz, 1H), 7.52 (d, J = 7.9 Hz, 2H), 7.41 (t, J = 7.5 Hz, 1H), 7.25 (d, J = 7.1 Hz, 1H), 2.47 (s, 3H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 150.0, 147.3, 138.8, 137.8, 133.9, 133.1, 129.2, 129.2, 129.0, 128.8, 128.1, 128.0, 127.9, 126.9, 124.5, 21.5.