1 H NMR ( CDCl 3 ) δ 8 . 57 ( 1 H , ddd , J = 4 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 56 ( 1 H , dd , J = 7 . 9 , 1 . 8 Hz ) , 7 . 29 ( 1 H , dd , J = 7 . 9 , 4 . 9 Hz ) , 7 . 19 - 7 . 08 ( 3 H , m ) , 4 . 63 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 57 ( 1 H , dd , J = 14 . 7 , 5 . 5 Hz ) , 3 . 99 ( 1 H , s ) , 3 . 85 ( 1 H , d , J = 11 . 0 Hz ) , 3 . 76 ( 1 H , br s ) , 3 . 72 ( 1 H , d , J = 11 . 0 Hz ) , 2 . 50 - 2 . 40 ( 3 H , m ) , 2 . 03 ( 1 H , m ) .