1H NMR (500 MHz, DMSO‑d 6) δ 8.47 (d, J = 1.7 Hz, 1H), 8.32 (s, 1H), 8.28 (s, 1H), 8.15 (d, J = 8.3 Hz, 1H), 8.12 (s, 1H), 8.11 (s, 1H), 7.88 (dd, J = 8.6 Hz, J = 1.8 Hz, 1H), 7.36 (br. s, 2H), 7.31 (br. s, 2H), 5.90 (d, J = 5.2 Hz, 1H), 5.82 (d, J = 5.4 Hz, 1H), 5.61 (d, J = 6.0 Hz, 1H), 5.43 (d, J = 5.1 Hz, 1H), 5.38 (dd, J = 6.6 Hz, J = 4.8 Hz, 1H), 5.30 (d, J = 5.3 Hz, 1H), 4.65 (q, J = 5.4 Hz, 1H), 4.37 (t, J = 5.1 Hz, 1H), 4.31 (q, J = 4.7 Hz, 1H), 4.19–4.10 (m, 2H), 3.91 (q, J = 3.6 Hz, 1H), 3.87–3.63 (m, 4H), 3.61–3.45 (m, 4H).