1 H - NMR ( 400 MHz , CDCl 3 ) δ = 1 . 95 ( 2 H , m , CH 2 ) , 2 . 48 ( 2 H , t , J = 6 . 51 Hz , CH 2 ) , 2 . 53 ( 2 H , t , J = 6 . 10 Hz , CH 2 ) , 2 . 67 ( 4 H , t , J = 4 . 45 Hz , 2 CH 2 ) , 3 . 25 ( 4 H , t , J = 4 . 43 Hz , 2 CH 2 ) , 6 . 84 - 7 . 74 ( 7 H , m , Ph ) , 8 . 84 ( 1 H , bs , NH ) ;