H 1 - NMR [ CDCl 3 , 300 MHz ] 3 . 38 ( 3 H , s ) , 6 . 63 - 6 . 65 ( 1 H , dd , J = 1 . 44 Hz , J = 5 . 25 Hz ) , 6 . 92 ( 1 H , s ) , 7 . 31 - 7 . 33 ( 3 H , m ) , 7 . 51 - 7 . 54 ( 2 H , m ) , 7 . 56 - 7 . 63 ( 3 H , m ) , 7 . 97 - 8 . 03 ( 3 H , m ) 8 . 84 ( 1 H , s ) . 수율 = 41 %.