1 H NMR ( 300 MHz , DMSO - d 6 ) δ 9 . 02 ( s , 1 H ) , 8 . 80 ( s , 1 H ) , 7 . 90 ( d , 2 H , J = 8 . 6 Hz ) , 7 . 63 ( d , 2 H , J = 8 . 6 Hz ) , 7 . 48 ( d , 2 H , J = 8 . 8 Hz ) , 7 . 35 ( t , 2 H , J = 7 . 7 Hz ) , 7 . 08 ( t , 1 H , J = 7 . 4 Hz ) , 6 . 97 ( m , 4 H ) , 3 . 13 ( t , 2 H , J = 7 . 2 Hz ) , 2 . 75 ( t , 2 H , J = 7 . 2 Hz ) , 2 . 38 ( m , 4 H ) , 1 . 44 ( m , 4 H ) , 1 . 35 ( m , 2 H ) ; LC / MS : 484 ( M ++ 1 ) .