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6,6′-bis(hydroxymethyl)-2,2′-bipyridine 5,5'-diMethoxycarbonyl-2,2'-bipyridine DIETHYL 2,2'-BIPYRIDINE-6,6'-DICARBOXYLATE 2,2'-Bipyridyl-5,5'-dialdehyde 4,4'-Dimethyl-2,2'-bipyridyl 6,6'-Dimethyl-2,2'-dipyridyl 4,4'-Bis(hydroxymethyl)-2,2'-bipyridine 2,2'-Bipyridine-4,4'-dicarboxylic acid 4,4'-Bis(methoxycarbonly)-2,2'-bipyridine 2,2'-Bipyridine-3,3'-dicarboxylic acid dimethyl ester