1 H NMR ( 400 MHz , CDCl 3 ) δ 9 . 10 ( s , 1 H ) , 8 . 39 ( t , J = 2 . 9 Hz , 1 H ) , 8 . 30 ( s , 1 H ) , 8 . 06 ( d , J = 3 . 0 Hz , 1 H ) , 7 . 93 ( dt , J = 14 . 6 , 3 . 2 Hz , 1 H ) , 7 . 80 - 7 . 69 ( m , 2 H ) , 7 . 68 - 7 . 50 ( m , 3 H ) , 7 . 37 ( d , J = 15 . 0 Hz , 1 H ) , 3 . 54 ( s , 2 H ) , 2 . 55 - 2 . 42 ( m , 4 H ) , 2 . 41 - 2 . 30 ( m , 4 H ) , 2 . 23 ( s , 1 H ) , 2 . 22 - 2 . 00 ( m , 4 H ) , 1 . 02 - 0 . 40 ( m , 4 H ) . LR - MS ( ESI ) m / z 577 ( M + 1 ) .