¹H NMR (400 MHz, CDCl₃) δ 10.35 (s, 1H), 9.43 (dd, J = 9.3, 6.0 Hz, 1H), 7.97 (d, J = 7.3 Hz, 1H), 7.59 (d, J = 7.3 Hz, 1H), 7.53 – 7.48 (m, 1H), 7.45 (ddd, J = 8.7, 4.8, 1.7 Hz, 3H), 7.24 (dd, J = 14.0, 5.4 Hz, 2H). ¹³C NMR (101 MHz, CDCl₃) δ 193.17, 164.04, 162.45, 161.57, 159.98, 145.52 (d, J = 5.3 Hz), 135.46 (dd, J = 45.0, 2.7 Hz), 133.63 (d, J = 8.4 Hz), 131.27 (d, J = 8.2 Hz), 130.78, 128.66 – 127.58 (m), 127.07, 118.81 (d, J = 24.3 Hz), 115.71 (d, J = 21.6 Hz), 110.17 (d, J = 22.1 Hz).