¹H NMR (400 MHz, CDCl3) δ 10.57 (s, 1H), 9.25 (d, J = 9.2 Hz, 1H), 8.11 (d, J = 7.5 Hz, 1H), 8.05 (s, 1H), 7.98 (d, J = 9.2 Hz, 1H), 7.78 (d, J = 8.7 Hz, 1H), 7.73 (d, J = 7.5 Hz, 1H), 7.60 – 7.56 (m, 2H), 7.45 (t, J = 7.4 Hz, 1H), 7.36 (d, J = 8.4 Hz, 1H), 7.02 (t, J = 7.8 Hz, 1H). ¹³C NMR (101 MHz, CDCl3) δ 193.29, 147.47, 139.82, 136.13, 132.04, 131.08, 130.61, 129.76, 128.81, 128.41, 128.06, 126.94, 126.77, 126.04, 125.02.