13C NMR (125 MHz, CDCl3) δ 157.1, 155.8, 155.5, 153.2, 152.9, 150.9, 149.5, 148.9, 139.7, 139.6, 134.2, 131.5, 120.4, 120.2, 114.7 (2C), 106.7, 90.5, 87.5, 84.5, 84.4, 84.4, 82.8, 82.6, 70.7, 69.6, 61.5, 56.8, 50.2, 47.1, 27.2, 26.2, 25.9, 25.4, 18.6, 18.2, −4.3, −4.8, −5.2.