1 H NMR ( 499 . 802 MHz , DMSO ) δ 2 . 60 ( 4 H , t ) , 3 . 44 ( 3 H , s ) , 3 . 62 ( 4 H , t ) , 3 . 96 ( 2 H , s ) , 7 . 58 - 7 . 67 ( 3 H , m ) , 7 . 70 - 7 . 75 ( 1 H , m ) , 7 . 99 - 8 . 02 ( 1 H , m ) , 8 . 27 ( 1 H , d ) ; m / z = 441 [ M + H ] +.