1 H NMR ( 399 . 9 MHz , CDCl 3 ) δ 1 . 75 - 1 . 79 ( 2 H , m ) , 1 . 88 - 2 . 02 ( 2 H , m ) , 3 . 29 - 3 . 35 ( 2 H , m ) , 3 . 92 ( 3 H , s ) , 4 . 03 - 4 . 16 ( 2 H , m ) , 5 . 14 ( 2 H , s ) , 6 . 72 ( 1 H , d ) , 7 . 36 ( 5 H , m ) , 7 . 66 ( 1 H , dd ) , 8 . 24 ( 1 H , d ) ; m / z = 343 [ M + H ] +.