2,3,5,6-TETRACHLOROPYRIDINE 2402-79-1 5-20-05-00421 (Beilstein Handbook Reference) BRN 0129639 EINECS 219-283-9 HSDB 5874 NSC 2009 Pyridine, 2,3,5,6-tetrachloro- Tetrachloropyridine, 2,3,5,6-