1 H NMR ( 300 MHz , DMSO - d 6 ) δ 7 . 38 - 7 . 33 ( m , 1 H ) , 7 . 26 ( d , J = 10 . 5 Hz , 1 H ) , 7 . 09 - 7 . 03 ( m , 1 H ) , 6 . 98 - 6 . 95 ( m , 1 H ) , 6 . 46 ( s , 2 H ) , 5 . 77 - 5 . 71 ( m , 1 H ) , 4 . 31 - 4 . 16 ( m , 4 H ) , 3 . 08 ( s , 3 H ) , 1 . 23 - 1 . 15 ( m , 3 H ) .