1H NMR (400 MHz, CDCl3) δ 7.73 (d, J = 8.3 Hz, 2H), 7.27 (d, J = 8.1 Hz, 2H), 5.86 (s, 1H), 5.62 (s, 1H), 3.52 (s, 2H), 2.52 (s, 3H), 2.12 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 196.0, 145.4, 143.8, 133.5, 130.1, 124.8, 124.7, 35.6, 15.5, 14.8. HRMS (EI): calcd for C12H14OS2: 238.0486; found: 238.0481.