The easiest thing is to use \Q when interpolating the string into your regex operator.

But why does that work? It changes ( to \(, etc. You would write m/\(Right\)/ normally. When interpolating, it's confusing because the backslashes are used by both the quote and the regex, and parens are not special to quotes. You would have to get a backslash into the regex, and that would require escaping that out in the quote! $Symbol= "\\(Right\\)".