¹H NMR (400 MHz, CDCl₃) δ 7.50 (d, J = 8.3 Hz, 2H), 7.32 (d, J = 8.3 Hz, 2H), 6.70 (dd, J = 17.6, 10.9 Hz, 1H), 5.79 (d, J = 17.6 Hz, 1H), 5.33 (d, J = 10.9 Hz, 1H). ¹³C{H} NMR (101 MHz, CDCl₃) δ 136.5, 135.7, 131.6, 127.8, 121.6, 114.6。