¹H NMR (400 MHz, CDCl₃) δ 9.71 (s, 1H), 7.28 (t, J = 7.9 Hz, 1H), 6.94 – 6.66 (m, 3H), 3.79 (s, 3H), 3.63 (s, 2H). ¹³C NMR (101 MHz, CDCl₃) δ 199.15, 159.91, 133.17, 129.85, 121.73, 115.13, 112.67, 55.02, 50.36. GC-MS (m/z): 150。