21563-97-3 | (Benzyl)[4-[[4-[(benzyl)ethylammonio]phenyl](2,4-disulfonatophenyl)methylen]cyclohexa-2,5-dien-1-yliden](ethyl)ammonium | (benzyl)[4-[[4-[(benzyl)ethylammonio]phenyl](2,4-disulphonatophenyl)methylene]cyclohexa-2,5-dien-1-ylidene](ethyl)ammonium |