Hz, DMSO‑d 6) δ 8.37 (s, 1H), 8.33 (s, 1H), 8.14 (s, 1H), 8.13 (s, 1H), 7.38 (br. s, 2H), 7.29 (br. s, 2H), 5.97 (d, J = 6.3 Hz, 1H), 5.84 (d, J = 5.3 Hz, 1H), 5.52–5.32 (m, 3H), 5.19 (d, J