using System;

using System.Text.RegularExpressions;

​

var output = Regex.Replace(

    "link: <http://www.google.com|www.google.com> link1: <http://www.jira.com|www.jira.com>\n\n\n",

    @"<[^|]*\|([^>]*)>",

    "$1");

​

Console.WriteLine(output);