1 H NMR ( 300 MHz , CDCl 3 ) δ 8 . 17 ( s , 1 H ) , 8 . 06 ( d , 2 H , J = 8 . 4 Hz ) , 7 . 81 ( d , 2 H , J = 8 . 4 Hz ) , 7 . 77 ( d , 2 H , J = 8 . 4 Hz ) , 7 . 43 ( d , 2 H , J = 8 . 1 Hz ) , 3 . 14 ( t , 2 H , J = 7 . 5 Hz ) , 2 . 89 ( t , 2 H , J = 7 . 6 Hz ) , 2 . 48 ( m , 4 H ) , 1 . 58 ( m , 4 H ) , 1 . 45 ( m , 2 H ) ; MS ( m / z ) : 410 ( M +).