Dihydrogen (ethyl)[4-[4-[ethyl(3-sulphonatobenzyl)amino]-2'-sulphonatobenzhydrylidene]cyclohexa-2,5-dien-1-ylidene](3-sulphonatobenzyl)ammonium, dipotassium salt
Dihydrogen (ethyl)[4-[a-[4-[ethyl(3-sulphonatobenzyl)amino]phenyl]-2-sulphonatobenzylidene]cyclohexa-2,5-dien-1-ylidene](3-sulphonatobenzyl)ammonium, potassium sodium salt