1 H NMR ( CD 3 OD , 400 MHz ) δ 8 . 48 ( s , 1 H ) , 8 . 28 ( s , 1 H ) , 8 . 06 ( d , J = 9 . 5 Hz , 1 H ) , 7 . 54 - 7 . 49 ( m , 7 H ) , 7 . 38 - 7 . 29 ( m , 5 H ) , 7 . 19 ( d , J = 8 . 6 Hz , 2 H ) , 7 . 11 ( dd , J = 2 . 5 Hz , 9 . 5 Hz , 1 H ) , 6 . 86 ( d , J = 2 . 4 Hz , 1 H ) , 3 . 94 ( s , 3 H ) , 3 . 73 ( s , 3 H ) , 2 . 48 ( s , 3 H ) .