¹H NMR (400 MHz, CDCl₃): δ 7.53 (d, J = 7.5 Hz, 1H), 7.47 (t, J = 8.9 Hz, 2H), 7.39 (dd, J = 14.8, 6.8 Hz, 1H), 7.14 (s, 1H), 7.06-6.94 (m, 4H), 3.86 (s, 3H), 3.83 (s, 3H), 2.32 (s, 3H). ¹³C NMR (100 MHz, CDCl₃): δ 182.3, 157.5, 157.2, 153.4, 151.6, 132.2, 131.2, 130.7, 129.69, 127.8, 123.1, 120.4, 120.2, 120.2, 118.4, 111.6, 111.3, 55.8, 55.5, 17.8. HRMS (EI): calcd for C₂₀H₁₈O₄S: 354.0926; found, 354.0921.