1 H NMR ( 600 MHz , CDCl 3 ) δ = 7 . 52 ( d , J = 8 Hz , 2 H ) , 7 . 34 - 7 . 31 ( m , 1 H ) , 7 . 17 ( d , J = 8 Hz , 2 H ) , 6 . 94 - 6 . 91 ( m , 1 H ) , 6 . 55 ( t , J = 6 Hz , 1 H ) , 4 . 91 - 4 . 84 ( m , 1 H ) , 4 . 12 ( t , J = 9 Hz , 1 H ) , 3 . 95 - 3 . 84 ( m , 4 H ) , 3 . 81 - 3 . 73 ( m , 3 H ) , 3 . 51 ( s , 3 H ) , 1 . 39 ( s , 6 H )