1 H - NMR ( 400 MHz , CDCl 3 ) δ = 1 . 95 ( 2 H , m , CH 2 ) , 2 . 46 ( 2 H , t , J = 6 . 82 Hz , CH 2 ) , 2 . 51 ( 2 H , t , J = 6 . 56 Hz , CH 2 ) , 2 . 64 ( 4 H , t , J = 4 . 94 Hz , 2 CH 2 ) , 3 . 22 ( 4 H , t , J = 4 . 93 Hz , 2 CH 2 ) , 6 . 90 - 7 . 48 ( 9 H , m , Ph ) , 8 . 51 ( 1 H , bs , NH )