“…1 H NMR (400 MHz, CDCl 3 ): = 7.34-7.28 (m, 4 H), 7.24-7.20 (m, 1 H), 6.83 (d, J = 19.9 Hz, 3 H), 5.13 (s, 1 H), 4.22-4.17 (m, 4 H), 3.35 (s, 3 H) 13. C NMR (101 MHz, CDCl 3 ): = 143.5, 143.0, 142.3, 135.6, 128.5, 127.5, 126.8, 120.2, 117.2, 116.0, 85.0, 64.4, 57.1.The spectroscopic data match the literature 21. …”