1 H NMR ( 399 . 9 MHz , CDCl 3 ) δ 1 . 76 - 1 . 79 ( 2 H , m ) , 1 . 94 - 2 . 08 ( 2 H , m ) , 3 . 26 - 3 . 37 ( 2 H , m ) , 4 . 12 - 4 . 27 ( 2 H , m ) , 5 . 16 ( 2 H , s ) , 5 . 17 ( 1 H , s ) , 7 . 32 - 7 . 38 ( 5 H , m ) , 8 . 05 ( 1 H , m ) , 8 . 79 ( 1 H , d ) , 8 . 90 ( 1 H , d ) ; m / z = 381 [ M + H ] +.