¹H NMR (400 MHz, CDCl₃) δ 9.15 (s, 1H), 8.27 (s, 1H), 7.94 (s, 1H), 7.78 (d, J = 8.2 Hz, 1H), 7.71 (d, J = 7.6 Hz, 2H), 7.52 (t, J = 7.3 Hz, 2H), 7.43 (t, J = 6.9 Hz, 2H), 2.60 (s, 3H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 149.6, 147.3, 139.9, 138.0, 133.2, 133.1, 129.4, 129.1, 128.0, 128.0, 127.6, 127.3, 126.1, 21.9.