1H NMR (400 MHz, CDCl3) δ 7.59 (t, J = 8.1 Hz, 3H), 7.51 (d, J = 7.8 Hz, 2H), 7.47 – 7.39 (m, 7H), 7.36 (d, J = 8.1 Hz, 3H), 7.29 (dd, J = 16.6, 8.7 Hz, 2H), 7.16 (d, J = 7.0 Hz, 1H). 13C NMR (101 MHz, CDCl3) δ 196.59, 155.27, 145.36, 140.64, 140.36, 133.49, 132.83, 131.92, 130.81, 130.35, 129.75, 129.34, 128.98, 128.88, 128.75, 128.52, 127.37, 126.99, 126.76, 123.02, 121.27.