1H NMR (400 MHz, CDCl3) δ 8.37 (s, 1H), 8.16 (t, J = 8.5 Hz, 3H), 7.88 (d, J = 8.5 Hz, 1H), 7.68 (d, J = 8.6 Hz, 1H), 7.60 (d, J = 8.6 Hz, 1H), 7.55-7.48 (m, 3H). 13C NMR (100 MHz, CDCl3) δ 158.2, 148.9, 139.1, 136.7, 132.0, 129.8, 129.7, 128.9, 128.7, 127.6, 125.8, 123.8, 119.3.