Pyridine Hydrochloride is the hydrochloride salt of pyridine, a basic six-membered heterocyclic ring. Pyridine is a base structure present in many biologically active compounds like the vitamins niacin and pyridoxal. Pyridine is used in dehalogenation reactions and can be used as a base in condensation reactions.Form:White to Off-White SolidMelting Point:138-142°CSolubility:Methanol, Water