¹H NMR (700 MHz, CDCl₃) δ 8.43 (s, 1H), 8.22 (q, J = 2.1 Hz, 1H), 7.71 (td, J = 7.9, 1.8 Hz, 1H), 7.32 (td, J = 7.9, 6.1 Hz, 1H), 7.09 (d, J = 7.6 Hz, 1H), 7.04 (m, J = 3.7 Hz, 1H), 7.00 (td, J = 8.5, 2.4 Hz, 1H), 3.74 (s, 1H).