1 H NMR ( 600 MHz , CDCl 3 ) δ = 7 . 57 ( d , J = 9 Hz , 2 H ) , 7 . 31 ( d , J = 4 . 2 Hz , 1 H ) , 7 . 29 ( d , J = 9 Hz , 2 H ) , 7 . 04 ( d , J = 4 . 2 Hz , 1 H ) , 6 . 80 ( t , J = 6 Hz , 1 H ) , 4 . 92 - 4 . 86 ( m , 1 H ) , 4 . 14 ( t , J = 9 Hz , 1 H ) , 3 . 94 - 3 . 86 ( m , 2 H ) , 3 . 82 - 3 . 74 ( m , 2 H ) , 2 . 81 ( t , J = 6 . 6 Hz , 2 H ) , 1 . 30 - 1 . 22 ( m , 1 H ) , 1 . 02 - 0 . 96 ( m , 2 H ) , 0 . 64 - 0 . 58 ( m , 2 H )