$re = '/,(\d+)\(([^)]+)\)/m';
$str = ',545(Users),66049(CONSOLE LOGON),11(Authenticated Users),4095(CurrentSession),66048(LOCAL)';
$subst = "'\2',\1\n";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php