“…Compound 3d was obtained as a red solid (mp: 216-218 1C) with 82% yield. 1 H NMR (500 MHz, DMSO-d 6 ) d 10.61 (s, 2H), 7.34 (d, J = 7.5 Hz, 2H), 7.27-7.23 (m, 4H), 7.17-7.14 (m, 1H), 6.81 (d, J = 2.0 Hz, 2H), 6.70-6.68 (m, 4H), 5.71 (s, 1H), 3.57 (s, 6H). 13…”