1H NMR (400 MHz, CDCl3) δ 7.72–7.66 (m, 2H), 7.14 (t, J = 4.3 Hz, 1H), 5.87 (s, 1H), 5.82 (s, 1H), 3.52 (s, 2H), 2.10 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 188.3, 144.2, 143.4, 134.3, 134.0, 127.9, 123.4, 35.6, 15.3. HRMS (EI): calcd for C9H10OS2: 198.0173; found: 198.0170.