1 H NMR ( CDCl 3 ) δ 8 . 60 ( 1 H , ddd , J = 4 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 59 ( 1 H , br d , J = 6 . 1 Hz ) , 7 . 45 ( 1 H , ddd , J = 7 . 9 , 1 . 8 , 1 . 2 Hz ) , 7 . 26 ( 1 H , m ) , 7 . 18 ( 1 H , dd , J = 7 . 9 , 2 . 4 Hz ) , 7 . 08 ( 1 H , dd , J = 8 . 6 , 2 . 4 Hz ) , 4 . 87 - 4 . 71 ( 3 H , m ) , 4 . 65 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 3 . 77 ( 1 H , br ) , 3 . 62 ( 1 H , br ) , 3 . 20 ( 1 H , d , J = 17 . 1 Hz ) , 3 . 06 ( 1 H , d , J = 17 . 1 Hz ) , 2 . 73 ( 1 H , m ) , 2 . 43 - 2 . 37 ( 2 H , m ) , 2 . 18 ( 1 H , m ) .