1H NMR (400 MHz, CDCl3): δ 8.18 (d, J = 8.5 Hz, 1H), 7.99 (s, 1H), 7.47 (s, 1H), 7.39 (d, J = 8.6 Hz, 1H), 2.41 (s, 3H). 13C NMR (100 MHz, CDCl3): δ 174.8, 156.3, 153.3, 139.9, 127.5, 126.3, 122.6, 121.6, 118.1, 16.0. HRMS (EI): calcd for C10H7ClO2S: 225.9855; found, 225.9859.