1,3-Naphthalenedisulfonic acid, 6-(4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)- 335149-63-8 6-(4,5-Dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)naphthalene-1,3-disulphonic acid 7277-87-4 EINECS 230-692-1