1H NMR (600 MHz, CDCl3) δ 8.32 (s, 1H), 8.31 (s, 1H), 8.17 (s, 1H), 7.90 (s, 1H), 6.11 (d, J = 3.6 Hz, 1H), 6.02 (m, 5H), 5.45 (dd, J = 6.5 Hz, J = 2.2 Hz, 1H), 4.91 (dd, J = 6.6 Hz, J = 3.3 Hz, 1H), 4.51 (t, J = 5.3 Hz, 1H), 4.32–4.23 (m, 2H), 4.08 (dt, J = 6.1 Hz, J = 3.2 Hz, 1H), 3.99 (dd, J = 11.5 Hz, J = 3.6 Hz, 1H), 3.76 (dd, J = 11.5 Hz, J = 2.8 Hz, 1H), 3.71–3.60 (m, 5H), 2.77 (dd, J = 13.5 Hz, J = 6.9 Hz, 1H), 2.74–2.69 (m, 2H), 2.64 (dd, J = 13.5 Hz, J = 6.8 Hz, 1H), 2.51–2.44 (m, 2H), 2.32–2.18 (m, 2H), 1.69–1.61 (m, 2H), 1.58 (s, 3H), 1.37 (s, 3H), 0.92 (s, 9H), 0.90 (s, 9H), 0.13–0.04 (m, 12H).