1 H NMR ( 400 MHz , CDCl 3 ) δ 9 . 35 ( s , 1 H ) , 8 . 25 ( d , J = 9 . 0 Hz , 1 H ) , 8 . 19 ( s , 1 H ) , 8 . 09 ( d , J = 2 . 3 Hz , 1 H ) , 7 . 66 ( dd , J = 8 . 8 , 2 . 3 Hz , 1 H ) , 5 . 02 ( tt , J = 12 . 0 , 3 . 8 Hz , 1 H ) , 4 . 30 ( ddd , J = 11 . 9 , 4 . 6 , 1 . 6 Hz , 1 H ) , 3 . 77 - 3 . 89 ( m , 2 H ) , 2 . 33 - 2 . 46 ( m , 2 H ) , 2 . 09 - 2 . 22 ( m , 1 H ) , 1 . 83 - 1 . 95 ( m , 1 H ) , 1 . 38 ( d , J = 6 . 3 Hz , 3 H ) .