27926-72-3 4,4'-Bipyridine 4,4'-Bipyridyl 4,4'-DIPYRIDYL 4,4'-Dipyridine 4,4'-Dipyridyl hydrate 4,4-Bipyridyl 4,4-Dipyridyl 4-(4-Pyridyl)pyridine 5-23-08-00028 (Beilstein Handbook Reference) 553-26-4 AI3-00138 BRN 0113176 CCRIS 2363 EINECS 209-036-3 NSC 404423 gamma,gamma'-Bipyridyl gamma,gamma'-Dipyridyl