1 H NMR ( 400 MHz , C 6 D 6 ) δ 7 . 42 - 7 . 35 ( m , 6 H ) , 7 . 30 ( d , J = 2 . 5 Hz , 2 H ) , 7 . 21 ( dd , J = 8 . 6 , 2 . 5 Hz , 2 H ) , 7 . 11 ( d , J = 2 . 3 Hz , 2 H ) , 6 . 95 ( d , J = 2 . 3 Hz , 2 H ) , 6 . 72 ( d , J = 8 . 6 Hz , 2 H ) , 5 . 43 ( s , 2 H ) , 3 . 81 ( br s , 4 H ) , 2 . 58 ( t , J = 7 . 8 Hz , 4 H ) , 1 . 66 - 1 . 56 ( m , 4 H ) , 1 . 38 - 1 . 22 ( m , 74 H ) , 1 . 17 - 1 . 08 ( m , 2 H ) , 0 . 90 - 0 . 84 ( m , 6 H ) , 0 . 76 ( d , J = 7 . 4 Hz , 12 H ) .