¹H NMR (400 MHz, CDCl₃) δ 9.18 (s, 1H), 8.26 (s, 1H), 8.15 (d, J = 8.3 Hz, 1H), 7.87 (d, J = 8.1 Hz, 1H), 7.75 – 7.63 (m, 3H), 7.57 (t, J = 7.5 Hz, 1H), 7.06 (d, J = 8.7 Hz, 2H), 3.88 (s, 3H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 159.9, 149.6, 146.7, 133.5, 132.6, 130.2, 129.2, 129.0, 128.5, 127.9, 127.0, 114.7, 55.4.