¹H NMR (400 MHz, CDCl₃) δ 7.66 (s, 1H), 7.51 (s, 1H), 6.87 (d, J = 8.0 Hz, 1H), 6.80 (d, J = 7.2 Hz, 2H), 6.34 (s, 1H), 5.97 (s, 2H), 5.46 (s, 1H), 5.10 (s, 1H). ¹³C NMR (101 MHz, CDCl₃) δ 148.42, 147.65, 145.38, 140.79, 129.83, 129.61, 122.08, 108.28, 108.13, 106.41, 104.15, 101.29. HRMS (EI): calcd for C₁₂H₁₀N₂O₂: 214.0742, found: 214.0746。