1 H NMR ( 399 . 9 MHz , DMSO - d 6 ) δ 1 . 67 ( 2 H , m ) , 1 . 88 ( 2 H , m ) , 2 . 81 ( 1 H , m ) , 3 . 07 - 3 . 14 ( 4 H , m ) , 3 . 79 ( 3 H , s ) , 4 . 18 ( 2 H , t ) , 4 . 41 ( 2 H , m ) , 6 . 14 ( 1 H , d ) , 6 . 89 ( 2 H , d ) , 7 . 19 ( 2 H , d ) , 7 . 30 ( 1 H , d ) , 7 . 66 ( 1 H , d ) , 8 . 24 ( 1 H , d ) ; m / z = 472 [ M + H ] +.