1 H NMR ( CDCl 3 ) δ 8 . 61 ( 1 H , ddd , J = 4 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 49 ( 1 H , ddd , J = 7 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 28 ( 1 H , m ) , 7 . 22 ( 1 H , dd , J = 7 . 9 , 4 . 9 Hz ) , 7 . 11 ( 1 H , br ) , 6 . 98 ( 1 H , dt , J = 8 . 6 , 1 . 8 Hz ) , 4 . 60 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 55 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 3 . 29 ( 1 H , br s ) , 2 . 65 ( 1 H , m ) , 2 . 38 ( 1 H , m ) , 2 . 25 - 2 . 11 ( 2 H , m ) , 1 . 63 ( 3 H , s ) .