1 H - NMR ( 500 MHz , CDCl 3 , δ ) : 7 . 96 ( d , J = 1 . 5 Hz , 4 H ) , 7 . 59 - 7 . 55 ( m , 12 H ) , 7 . 45 ( t , J = 7 . 5 Hz , 8 H ) , 7 . 35 - 7 . 31 ( m , 12 H ) , 7 . 07 - 7 . 01 ( m , 4 H ) , 7 . 00 - 6 . 94 ( m , 8 H ) , 6 . 76 - 6 . 74 ( m , 2 H ) , 6 . 58 - 6 . 54 ( m , 1 H ) , 6 . 45 ( t , J = 8 . 0 Hz , 2 H )