1H NMR (400 MHz, CDCl3) δ 7.58 (d, J = 6.9 Hz, 1H), 7.41 (s, 5H), 7.36 (d, J = 7.4 Hz, 1H), 7.31 – 7.26 (m, 1H), 7.18 (d, J = 7.6 Hz, 2H), 7.13 (d, J = 7.1 Hz, 1H), 7.08 (d, J = 7.6 Hz, 2H), 2.33 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 196.72, 154.62, 145.46, 137.66, 133.41, 132.96, 132.40, 130.81, 129.86, 129.18, 128.86, 128.78, 128.51, 127.77, 122.91, 121.10, 21.35.