1H NMR (600 MHz, DMSO‑d 6) δ 8.32 (s, 1H), 8.29 (s, 1H), 8.22–8.18 (m, 2H), 8.14 (s, 1H), 8.13 (s, 1H), 7.96–7.91 (m, 2H), 7.32 (br. s, 2H), 7.26 (br. s, 2H), 5.89 (d, J = 5.4 Hz, 1H), 5.79 (d, J = 5.6 Hz, 1H), 5.73–5.20 (m, 4H), 4.70 (t, J = 5.4 Hz, 1H), 4.34 (t, J = 5.1 Hz, 1H), 4.30–4.26 (m, 1H), 4.15 (t, J = 4.6 Hz, 1H), 4.09 (dt, J = 8.5 Hz, J = 4.3 Hz, 1H), 3.89 (q, J = 3.6 Hz, 1H), 3.75–3.70 (m, 2H), 3.66–3.63 (m, 1H), 3.60–3.29 (m, 5H).