1 H NMR ( CD 3 OD , 400 MHz ) δ 8 . 34 ( s , 1 H ) , 7 . 98 ( t , J = 6 . 1 Hz , 2 H ) , 7 . 39 ( d , J = 8 . 6 Hz , 2 H ) , 7 . 19 ( d , J = 8 . 6 Hz , 4 H ) , 6 . 99 - 6 . 92 ( m , 5 H ) , 6 . 80 ( d , J = 8 . 8 Hz , 2 H ) , 6 . 53 ( t , J = 2 . 4 Hz , 1 H ) , 3 . 10 ( s , 6 H ) , 3 . 03 ( dd , J = 3 . 2 Hz , 5 . 6 Hz , 12 H ) , 2 . 95 ( s , 6 H ) , 2 . 38 ( s , 3 H ) .