$re = '/https:\/\/domain\.com\/wp-content\/uploads\/.+-(?!(?:360x240|300x200|720x480))\d+x\d+\.jpg/';
$str = 'https://domain.com/wp-content/uploads/name-file-300x200.jpg
https://domain.com/wp-content/uploads/name-file-360x240.jpg
https://domain.com/wp-content/uploads/name-file-720x480.jpg
https://domain.com/wp-content/uploads/name-file-1200x768.jpg
https://domain.com/wp-content/uploads/name-file-1400x900.jpg';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
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