1 H NMR ( 399 . 9 MHz , DMSO - d 6 ) δ 1 . 30 ( 3 H , t ) , 3 . 54 ( 4 H , m ) , 3 . 79 ( 4 H , m ) , 4 . 26 ( 2 H , q ) , 7 . 04 ( 2 H , d ) , 7 . 66 ( 1 H , d ) , 7 . 83 ( 2 H , d ) , 8 . 30 ( 1 H , d ) ; m / z = 421 [ M + H ] +.