1 H NMR ( 700 . 03 MHz , DMSO - d 6 ) δ 2 . 47 ( 3 H , s ) , 3 . 56 ( 4 H , t ) , 3 . 79 ( 4 H , t ) , 7 . 03 - 7 . 04 ( 2 H , m ) , 7 . 66 ( 1 H , d ) , 7 . 84 - 7 . 86 ( 2 H , m ) , 8 . 30 ( 1 H , d ) ; m / z = 391 [ M + H ] +.