sed with special characters

I have this line that I want to use sed on:

--> ASD = $start ( *.cpp ) <--

where $start is not a varaiable, I want to use sed on it and replace all this line with:

ASD = $dsadad ( .cpp ) 

How can I make sed ignore special charactars, I tried adding back slash before special characters, but maybe I got it wrong, can some one show me an example?

Here is what i want :

sed 's/CPPS = \$(shell ls | grep \*\.cpp )/somereplace/' Makefile