1 H NMR ( 400 MHz , chloroform - d 1 ) δ = 7 . 94 ( d , J = 4 . 4 Hz , 1 H ) , 7 . 60 ( d , J = 8 . 8 Hz , 2 H ) , 7 . 45 ( d , J = 8 . 8 Hz , 2 H ) , 6 . 84 ( d , J = 4 . 4 Hz , 1 H ) , 5 . 01 - 4 . 98 ( m , 1 H ) , 4 . 13 - 4 . 04 ( m , 1 H ) , 3 . 77 ( t , J = 10 Hz , 2 H ) , 3 . 75 - 3 . 71 ( m 3 H ) , 3 . 38 ( t , J = 10 Hz , 2 H ) , 3 . 15 - 3 . 13 ( m , 1 H ) , 1 . 00 ( dd , J = 6 . 4 , 0 . 8 Hz , 6 H )