Synonyms: Ruthenate(4-),bis[[2,2'-bipyridine]-4,4'-dicarboxylato(2-)-N1,N1']bis(thiocyanato-N)-,tetrahydrogen, (OC-6-21)-; N 3; N 3 (dye); Ru 535; Ruthenium 535;cis-Bis(2,2'-bipyridine-4,4'-dicarboxylic acid)diisothiocyanatoruthenium;cis-Bis(4,4'-dicarboxy-2,2'-bipyridine)diisothiocyanatoruthenium;cis-Bis(isothiocyanato)-bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II);cis-Di(isothiocyanato)-bis(4,4'-dicarboxy-2,2'-bipyridine) ruthenium(II);cis-Dithiocyanatobis(N,N'-2,2'-bipyridyl-4,4'-dicarboxylic acid)ruthenium