using System;
using System.Text.RegularExpressions;
public class Test
{
    public static void Main()
    {   
        string findPattern = "(?<=(?:, |^)\").*?(?=\"(?:, |$))";
        string parametersText = "\"parameter1\", \"parameter2\", \"parameter3\"";
        MatchCollection mc = Regex.Matches(parametersText, findPattern);
        foreach (Match match in mc)
        {
            Console.WriteLine(match.Groups[0].Value);
        }
    }
}