1 H - NMR ( 400 MHz , CDCl 3 ) δ = 2 . 49 - 2 . 61 ( 8 H , m , 4 CH 2 ) , 2 . 71 ( 2 H , s , CH 2 ) , 3 . 48 ( 2 H , s , CH 2 ) , 3 . 98 - 4 . 02 ( 2 H , m , CH 2 ) , 4 . 07 - 4 . 11 ( 1 H , m , CH ) , 6 . 97 - 6 . 99 ( 2 H , d , J = 8 . 7 , Ph ) , 7 . 24 - 7 . 30 ( 4 H , m , Ph ) , 7 . 52 - 7 . 55 ( 2 H , d , J = 8 . 7 , Ph ) .