¹H NMR (400 MHz, CDCl₃) δ 8.96 (s, 1H), 7.88 (d, J = 5.0 Hz, 1H), 7.44 (s, 1H), 7.41 (dd, J = 4.6, 2.8 Hz, 1H), 7.32 (t, J = 7.2 Hz, 3H), 7.27 (t, J = 7.5 Hz, 2H), 7.10 (d, J = 4.8 Hz, 1H), 7.01 (d, J = 7.3 Hz, 2H), 5.80 (s, 2H). ¹³C{¹H} NMR (101 MHz, CDCl₃) δ 176.6, 143.5, 140.8, 137.5, 136.2, 134.3, 129.3, 128.9, 128.8, 128.6, 127.9, 127.4, 126.7, 125.7, 125.0, 124.9, 49.5. HRMS (EI) m/z: calcd for C₁₉H₁₄N₂OS₂, 350.0548; found, 350.0543.