1H NMR (400 MHz, CDCl3) δ 9.20 (s, 1H), 8.95 (s, 2H), 7.61 – 7.55 (m, 2H), 7.55 – 7.49 (m, 2H), 7.49 – 7.44 (m, 1H). 13C NMR (101 MHz, CDCl3) δ 157.38, 154.85, 134.33, 134.20, 129.40, 128.99, 126.95.