Synonyms: 2,3,5,6-Tetrachloro-4-(methanesulfonyl)-pyridine;2,3,5,6-Tetrachloro-4-(methylsulfonyl)pyridine;4-(Methylsulfonyl)-2,3,5,6-tetrachloropyridine;Algophase;Algophase PH025/d;Densil S;Densil S 100;Densil S 25;Dowco 282;Dowicil S 13;SA 1013;TCMS pyridine;