¹H NMR (400 MHz, Chloroform-d) δ 8.83 (s, 2H), 8.07 (s, 1H), 7.47 (d, J = 6.8 Hz, 4H), 7.44-7.38 (m, 2H), 7.28 (s, 2H), 2.48 (s, 6H). ¹³C{H} NMR (101 MHz, Chloroform-d) δ 146.7, 138.8, 137.7, 136.8, 133.0, 129.0, 129.0, 128.0, 124.3, 21.5。