1 H NMR ( 400 MHz , 메탄올 - d 4 ) δ 8 . 81 ( s , 1 H ) , 8 . 74 ( d , J = 2 . 1 Hz , 1 H ) , 8 . 67 ( d , J = 2 . 2 Hz , 1 H ) , 8 . 01 ( d , J = 5 . 1 Hz , 1 H ) , 7 . 97 ( s , 1 H ) , 7 . 21 ( d , J = 5 . 1 Hz , 1 H ) , 7 . 20 ( s , 1 H ) , 4 . 28 - 4 . 08 ( m , 1 H ) , 2 . 14 ( s , 3 H ) , 1 . 44 ( d , J = 6 . 4 Hz , 6 H ) .