2,2'-Dipyridyl disulfide 2,2'-Dipyridyldisulfide 2,2'-Dithiodipyridine 2-Dipyridyl disulfide 2127-03-9 2PDS Bis(2-pyridinyl) disulfide Bis(2-pyridyl) disulfide EINECS 218-343-1 NSC 677438 NSC 94055 Pyridine, 2,2'-dithiobis- (9CI) Pyridine, 2,2'-dithiodi- (8CI)