1 H - NMR ( 400 MHz , CDCl 3 ) δ = 1 . 98 ( 2 H , m , CH 2 ) , 2 . 52 ( 4 H , t , J = 6 . 66 Hz , 2 CH 2 ) , 2 . 64 ( 4 H , s , 2 CH 2 ) , 3 . 22 ( 4 H , s , 2 CH 2 ) , 8 . 13 ( 1 H , bs , NH ) , 6 . 76 - 8 . 24 ( 7 H , m , Ph ) ;