¹H NMR (400 MHz, CDCl₃) δ 9.71 (s, 1H), 7.14 (d, J = 8.2 Hz, 2H), 6.92 (d, J = 8.3 Hz, 2H), 3.80 (s, 3H), 3.62 (s, 2H). ¹³C NMR (101 MHz, CDCl₃) δ 199.41, 158.76, 130.47, 123.58, 114.23, 55.03, 49.44. GC-MS (m/z): 150。