1 H NMR ( 399 . 9 MHz , DMSO - d 6 ) δ 1 . 76 ( 2 H , m ) , 2 . 14 ( 2 H , m ) , 3 . 51 ( 2 H , m ) , 4 . 01 ( 2 H , m ) , 4 . 95 ( 1 H , m ) , 7 . 37 ( 1 H , m ) , 7 . 66 ( 1 H , d ) , 7 . 81 ( 1 H , m ) , 8 . 27 ( 1 H , d ) , 8 . 55 ( 1 H , m ) ; m / z = 390 [ M + H ] +.