1 H NMR ( 300 MHz , CDCl 3 ) δ 1 . 79 - 2 . 03 ( 3 H , m ) , 2 . 05 - 2 . 19 ( 1 H , m ) , 3 . 24 - 3 . 33 ( 2 H , m ) , 3 . 40 - 3 . 53 ( 2 H , m ) , 3 . 82 - 3 . 99 ( 3 H , m ) , 6 . 88 - 6 . 97 ( 2 H , m ) , 7 . 13 - 7 . 19 ( 2 H , m ) , 7 . 24 ( 1 H , d , J = 1 . 5 Hz ) , 7 . 34 ( 1 H , dd , J = 8 . 3 , 1 . 5 Hz ) , 7 . 58 ( 1 H , d , J = 8 . 3 Hz ) .