1H NMR (400 MHz, DMSO-d6) δ 7.90 – 7.84 (m, 1H), 7.83 – 7.76 (m, 1H), 7.66 – 7.57 (m, 2H), 3.94 (s, 3H), 2.74 (s, 3H), 1.51 (s, 6H). 13C NMR (101 MHz, DMSO) δ 196.50, 142.50, 142.02, 129.83, 129.31, 123.70, 115.53, 54.39, 35.01, 22.13, 14.39. LCMS m/z: 174.2 [M – I-].