1 H NMR ( 499 . 802 MHz , DMSO - d 6 ) δ 1 . 81 - 1 . 92 ( 2 H , m ) , 2 . 65 - 2 . 70 ( 2 H , m ) , 2 . 77 - 2 . 83 ( 2 H , m ) , 3 . 70 ( 2 H , s ) , 3 . 71 - 3 . 76 ( 2 H , m ) , 3 . 76 - 3 . 80 ( 2 H , m ) , 7 . 18 - 7 . 27 ( 2 H , m ) , 7 . 34 ( 1 H , d ) , 7 . 41 ( 1 H , d ) , 7 . 49 ( 1 H , d ) , 8 . 21 ( 1 H , d ) ; m / z = 411 [ M + H ] +.