Extract contents from a string using regex

Question

I have a big string , with this line specifically:

/CIP3AdmSeparationNames [(Cyan)(Magenta)(Yellow)(Black)(PANTONE 647 C)] def

 

I'm trying to extract ONLY the contents between Parentheses from that string with regex - but not being able to, tried a lot of combinations but none of 'em worked.

 

The string has many lines - i just need this content. I don't wanna use .Indexof or .Substring - they were giving me bugs all the time.

 

Thanks in advance for any help !