1 H - NMR ( CDCl 3 ) δ 8 . 56 - 8 . 65 ( 1 H , m ) , 7 . 50 ( 1 H , br d , J = 8 . 1 Hz ) , 7 . 45 ( 1 H , d , J = 2 . 2 Hz ) , 7 . 30 - 7 . 39 ( 1 H , m ) , 7 . 13 - 7 . 29 ( 3 H , m ) , 4 . 60 ( 2 H , dd , J = 10 . 0 , 5 . 9 Hz ) , 2 . 90 - 3 . 09 ( 2 H , m ) , 2 . 29 - 2 . 45 ( 2 H , m ) , 2 . 05 - 2 . 17 ( 2 H , m ) .