$re = '/(<a href=\\\\"http:\/\/example\.com\/path-pattern-to-match\/)([^>]*)\\\\">/i';
$str = '<a href=\\"http://example.com/path-pattern-to-match/someArticle\\"> <a href=\\"http://example.com/path-pattern-to-match/subPath/onemoreSubpath/arbitrary-number-of-subpaths/someArticle\\">
';
$subst = "";
$result = preg_replace($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