1 H NMR ( CDCl 3 ) δ 8 . 61 ( 1 H , br d , J = 4 . 9 Hz ) , 7 . 48 ( 1 H , br d , J = 7 . 9 Hz ) , 7 . 26 ( 1 H , dd , J = 7 . 9 , 4 . 9 Hz ) , 7 . 23 ( 1 H , br ) , 7 . 12 ( 1 H , m ) , 6 . 98 ( 1 H , m ) , 4 . 75 ( 1 H , m ) , 4 . 65 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 57 ( 1 H , dd , J = 14 . 7 , 6 . 1 Hz ) , 4 . 40 ( 1 H , br s ) , 2 . 61 - 2 . 28 ( 3 H , m ) , 2 . 02 ( 1 H , m ) .