“…1 g; 68% yield; 1 H NMR (DMSO, 400 MHz), δ 9.90 (s, 1H), 8.16 (dd, J = 8.0, 1.0 Hz, 1H), 7.90 (d, J = 8.8 Hz, 2H), 7.82 (ddd, J = 8.4, 7.2, 1.6 Hz, 1H), 7.63 (d, J = 7.6 Hz, 1H), 7.60–7.52 (m, 1H), 7.32 (d, J = 8.8 Hz, 2H), 5.45 (s, 2H), 3.62 (s, 3H). Spectral properties were in accordance with the literature 23 .…”