¹H NMR (400 MHz, CDCl₃) δ 9.80 (s, 1H), 7.59 (dd, J = 13.5, 8.2 Hz, 4H), 7.45 (t, J = 7.6 Hz, 2H), 7.39 – 7.33 (m, 1H), 7.30 (d, J = 7.9 Hz, 2H), 3.74 (s, 2H). ¹³C NMR (101 MHz, CDCl₃) δ 199.26, 140.56, 140.42, 130.77, 130.02, 128.79, 127.71, 127.40, 127.04, 50.20. GC-MS (m/z): 196。