¹³C NMR (176 MHz, CDCl₃) δ 166.11 (s, 1C), 151.81 (s, 1C), 147.86 (s, 1C), 138.71 (s, 1C), 134.48 (s, 1C), 132.35 (s, 1C), 128.93 (s, 1C), 127.45 (s, 1C), 120.02 (s, 1C), 114.47 (s, 1C).