13C NMR (150 MHz, CDCl3) δ 155.8, 155.5, 153.2, 153.0, 149.7, 149.5, 148.9, 145.4, 140.2, 139.5, 128.4, 123.8, 120.5, 120.2, 114.7, 90.7, 87.3, 85.0, 84.5, 84.2, 82.8, 82.6, 69.7, 69.6, 61.5, 50.7, 47.7, 27.3, 26.2, 25.9, 25.4, 18.6, 18.2, −4.4, −4.7, −5.2, −5.3.