4,4'-(Dithiodimethylene)bispyridine dihydrochloride 4282-20-6 Bis(4-pyridylmethyl)disulphide dihydrochloride Pyridine, 4,4'-(dithiobis(methylene))bis-, dihydrochloride Pyridine, 4,4'-(dithiodimethylene)bis-, dihydrochloride