1 H - NMR ( 300 MHz , CDCl 3 , ppm ) : 9 . 14 ( s , 1 H ) 8 . 92 ( s , 1 H ) , 8 . 81 ( d , 1 H ) , 8 . 58 - 8 . 45 ( m , 3 H ) , 8 . 19 - 8 . 06 ( m , 4 H ) , 7 . 67 - 7 . 50 ( m , 2 H ) , 1 . 36 - 1 . 27 ( m , 21 H )