“…R F 0.5 (50:50 hexane/EtOAc). ν max /cm −1 (CH 2 Cl 2 ) 3405 (OH, NH), 2941, 1781, 1718, 1600. δ H (CDCl 3 , 300.1 MHz) 0.61 (d, J 6.9, 3H, CH 3 ), 1.94 (br s, 2H, OH and NH), 2.5 (m, 1H), 3.92 (dd, J 11.1 and 4.5, 1H), 4.18 (dd, J 11.1 and 9.6, 1H), 4.75 (d, J 15.6, 1H), 4.98 (d, J 15.6, 1H), 6.57 (d, J 8.1, 1H, Ar), 7.28-7.48(m, 7H, Ar). δ C (CDCl 3 , 75 MHz)11.59, 41.11, 64.65, 79.64, 104.78, 116.21, 122.11, 123.44, 127.01, 127.21 (2C), 127.89 (3C), 130.01, 132.39, 141.82, 196.58.…”