using System.Text.RegularExpressions;

using System;

public class Program

{

    public static void Main()

    {

        string mainstr = "\"" + "Operational Metrics~Copper C1 Cash Costs (US$/lb) - Lalor~9999" + "\"" + "*" + "\"" + "Operational Metrics~Canadian Dollars (Canadian $/US$)~9999" + "\"";

        string replacesfrom = @"""Operational Metrics~Copper C1 Cash Costs \(US\$\/lb\) - Lalor~9999""";

        string replacesto = "A10";

        string afterreplace = Regex.Replace(mainstr, replacesfrom, replacesto);

        Console.WriteLine(afterreplace);

    }

}