1 H NMR ( CDCl 3 ) δ 8 . 68 ( 1 H , ddd , J = 4 . 9 , 4 . 0 , 1 . 8 Hz ) , 7 . 61 ( 1 H , br dt , J = 7 . 9 , 1 . 8 Hz ) , 7 . 45 ( 1 H , d , J = 1 . 8 Hz ) , 7 . 40 - 7 . 35 ( 1 H , m ) , 7 . 29 - 7 . 15 ( 3 H , m ) , 6 . 19 ( 1 H , br d , J = 1 . 8 Hz ) , 5 . 35 ( 1 H , br d , J = 1 . 8 Hz ) , 4 . 67 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 59 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 3 . 58 ( 1 H , m ) , 3 . 12 ( 1 H , m ) .