MySQL 5.6

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CREATE TABLE IF NOT EXISTS `products_cross` (
  `id` int(6) unsigned NOT NULL,
  `GRPCD` int(10) unsigned NOT NULL,
  `brand` int(5) NOT NULL,
  PRIMARY KEY (`id`)
) DEFAULT CHARSET=utf8;
INSERT INTO `products_cross` (`id`, `GRPCD`, `brand`) VALUES
  ('1', '33111', '107'),
  ('2', '33111', '103'),
  ('3', '44111', '105'),
  ('4', '44111', '101');

SELECT * FROM products_cross


id
GRPCD
brand


1
33111
107

2
33111
103

3
44111
105

4
44111
101


DELETE FROM `products_cross` 
WHERE GRPCD NOT IN (SELECT GRPCD FROM (SELECT * FROM products_cross ) pc WHERE brand=107) 
SELECT * FROM products_cross


id
GRPCD
brand


1
33111
107

2
33111
103