1 H NMR ( 399 . 9 MHz , DMSO - d 6 ) δ 1 . 66 ( 2 H , m ) , 1 . 91 ( 2 H , m ) , 2 . 02 ( 3 H , s ) , 2 . 84 ( 1 H , m ) , 3 . 13 ( 2 H , m ) , 4 . 42 ( 2 H , m ) , 6 . 95 ( 1 H , m ) , 7 . 22 ( 1 H , m ) , 7 . 41 ( 1 H , m ) , 7 . 49 ( 1 H , s ) , 7 . 67 ( 1 H , d ) , 8 . 25 ( 1 H , d ) , 9 . 84 ( 1 H , s ) ; m / z = 405 [ M + H ] +.