2,7-Naphthalenedisulfonic acid, 5-4-chloro-6-4-2-(sulfooxy)ethylsulfonylphenylamino-1,3,5-triazin-2-ylamino-4-hydroxy-3-4-2-(sulfooxy)ethylsulfonylphenylazo-, tetrasodium salt

5-[[4-Chloro-6-[[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]amino]1,3,5-triazin-2-yl]amino]-4- hydroxy-3-[[4-[[2-(sulfooxy)ethyl]sulfonyl] phenyl]azo]-2,7-naphthalenedisulfonic acid tetrasodium salt