¹H NMR (400 MHz, CDCl₃) δ 9.74 (s, 1H), 7.44 (d, J = 7.9 Hz, 1H), 7.38 (s, 1H), 7.28 – 7.21 (m, 1H), 7.14 (q, J = 6.3 Hz, 1H), 3.67 (s, 2H). ¹³C NMR (101 MHz, CDCl₃) δ 198.35, 134.01, 132.60, 130.57, 130.43, 128.22, 122.94, 49.91. GC-MS (m/z): 197。