a bug and tar remover should do the trick, but you will need to wax afterwards.
If that doesnt get it out try a glaze/polish compound. I use mothers stage 2 sealant.
Failing that, bust out the clay bar.
<span style='color:gray'><span style='font-family:Courier'>1995 e36 3 Series RIP
1999 e46 3 Series BURN IN HELL
2000 MR-S Roadster= Current</span></span>