Pyridoxine disulfide was synthesized by heating pyridoxine thiosulfate in acid solution containing thiourea, iodide or thiocyanate. It was also prepared either by acid decomposition of isopropylidene pyridoxine disulfide, obtained from isopropylidene pyridoxine chloride and Na_2S_2,or by alkali decomposition of pyridoxine thiocyanate.
