1H NMR (400 MHz, CDCl3) δ 7.69 (s, 1H), 7.52 (s, 1H), 7.32 (d, J = 8.0 Hz, 2H), 6.92 (d, J = 8.0 Hz, 2H), 6.36 (s, 1H), 5.51 (s, 1H), 5.13 (s, 1H), 3.83 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 160.23, 145.34, 140.61, 129.47, 129.18, 128.15, 113.70, 106.24, 103.50, 55.14. GC-MS (m/z): 200。