1 H - NMR ( CDCl 3 ) δ 8 . 62 ( 1 H , dt , J = 4 . 7 , 1 . 6 Hz ) , 7 . 48 ( 1 H , d , J = 7 . 6 Hz ) , 7 . 41 ( 1 H , t , J = 7 . 0 Hz ) , 7 . 08 - 7 . 24 ( 3 H , m ) , 6 . 99 ( 1 H , td , J = 8 . 3 , 2 . 6 Hz ) , 4 . 53 - 4 . 67 ( 2 H , m ) , 3 . 14 - 3 . 41 ( 6 H , m ) , 3 . 10 ( 2 H , br s ) , 2 . 83 ( 1 H , br d , J = 12 . 6 Hz ) , 2 . 49 - 2 . 76 ( 1 H , m ) , 2 . 13 - 2 . 37 ( 3 H , m ) , 1 . 43 ( 3 H , s ) .