“…1 H NMR (400 MHz, CDCl 3 , δ, ppm): 7.59-7.43 (m, 3H), 7.25 (d, 2H), 6.73 (dd, J = 15.8, 12.1 Hz, 1H), 5.35 (s, 1H), 3.62-3.40 (m, 1H), 2.95-2.90 (m, 1H), 1.00 (s, 3H), 0.63 (s, 3H). 13 C NMR (100 MHz,CDCl 3 ,δ,ppm): 199.7,150.9,140.8,140.1,131.7,127.7,126.3,125.3,120.7,71.0,61.2,58.3,56.5,50.2,49.4,48.8,45.4,44.2,41.5,38.4,36.5,35.8,34.8,33.4,31.3,31.1,30.9,25.4,24.0,23.5,22.0,20.4,20.3,18.7, White 2,71.7,62.0,57.3,50.1,45.1,42.3,39.1,37.3,36.6,32.1,31.9,31.7,24.8,22.8,21.2,19.5, White solid, yield: 92 %,mp 154.9-155.8°C. 1 H NMR (400 MHz, CDCl 3 ) δ 7.50 (d,…”