“…1 H NMR (CDCl 3 , 400 MHz) δ 8.48 (d, J = 4.1 Hz, 1H), 8.40 (s, 1H), 8.25 (s, 1H), 7.52−7.35 (m, 3H), 7.11 (dd, J = 7.6, 4.9 Hz, 1H), 6.03 (s, 1H), 5.98 (s, 1H), 5.68 (s, 1H), 5.30 (s, 1H), 5.12 (s, 1H), 3.83 (s, 2H), 1.36 (s, 9H). 13 (17). 1 H NMR (400 MHz, CDCl 3 ) δ 8.18 (s, 1H), 8.06 (s, 1H), 7.48 (s, 1H), 7.19 (s, 1H), 7.08 (s, 4H), 6.28 (s, 1H), 5.87 (s, 1H), 5.08− 4.99 (m, 1H), 3.83 (s, 2H), 3.33 (s, 2H), 2.78 (s, 1H), 2.54 (s, 1H), 1.33 (s, 9H).…”