1 H NMR ( 700 . 03 MHz , DMSO - d 6 ) δ 2 . 31 ( 6 H , s ) , 3 . 17 ( 4 H , t ) , 3 . 73 ( 4 H , t ) , 6 . 95 - 6 . 97 ( 1 H , m ) , 7 . 00 ( 2 H , d ) , 7 . 66 ( 1 H , d ) , 8 . 27 ( 1 H , d ) ; m / z = 377 [ M + H ] +.