1 H NMR ( CDCl 3 ) δ 8 . 62 ( 1 H , ddd , J = 4 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 57 ( 1 H , dd , J = 7 . 9 , 1 . 2 Hz ) , 7 . 45 ( 1 H , d , J = 1 . 8 Hz ) , 7 . 35 - 7 . 31 ( 2 H , m ) , 7 . 27 ( 1 H , dd , J = 7 . 9 , 4 . 9 Hz ) , 7 . 19 ( 1 H , br d , J = 4 . 9 Hz ) , 4 . 62 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 573 ( 1 H , s ) , 4 . 566 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 3 . 55 ( 1 H , d , J = 16 . 5 Hz ) , 3 . 51 ( 1 H , d , J = 16 . 5 Hz ) , 3 . 14 ( 3 H , s ) , 3 . 07 ( 1 H , m ) , 2 . 63 ( 1 H , m ) , 2 . 40 ( 1 H , m ) , 2 . 18 ( 1 H , m ) .