¹H NMR (400 MHz, CDCl₃) δ 9.18 (s, 1H), 8.27 (s, 1H), 8.14 (d, J = 8.4 Hz, 1H), 7.87 (d, J = 8.1 Hz, 1H), 7.71 (t, J = 7.6 Hz, 1H), 7.62 (d, J = 7.0 Hz, 2H), 7.57 (t, J = 7.5 Hz, 1H), 7.33 (d, J = 7.5 Hz, 2H), 2.44 (s, 3H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 149.9, 147.1, 138.0, 134.9, 133.8, 132.8, 129.9, 129.2, 129.1, 128.1, 127.9, 127.2, 126.9, 21.2.