1 H - NMR ( 300 MHz , CDCl 3 ) : δ = 7 . 63 ( d , J = 6 . 6 Hz , 1 H ) , 7 . 58 ( d , J = 8 . 1 Hz , 1 H ) , 7 . 42 - 7 . 37 ( m , 4 H ) , 7 . 36 - 7 . 09 ( m , 14 H ) , 2 . 55 - 2 . 39 ( m , 1 H ) , 1 . 98 - 1 . 20 ( m , 51 H ) .