¹H NMR (400 MHz, CDCl₃) δ 8.94 (s, 1H), 8.18 (d, J = 8.4 Hz, 1H), 8.11 (s, 1H), 7.86 (d, J = 8.1 Hz, 1H), 7.75 (t, J = 7.6 Hz, 1H), 7.60 (t, J = 7.4 Hz, 1H), 7.34 (d, J = 8.6 Hz, 4H), 2.34 (s, 3H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 151.3, 146.8, 138.1, 135.8, 135.5, 134.8, 130.6, 130.2, 129.4, 129.2, 128.2, 127.9, 127.8, 126.9, 126.2, 20.4.