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system
Provide the molecular formula for the IUPAC named substance 2-[(Z)-2-(4-nitro-2-sulfophenyl)ethenyl]-5-[[4-[(E)-2-(4-nitro-2-sulfophenyl)ethenyl]-3-sulfophenyl]diazenyl]benzenesulfonic acid .
user
C28H20N4O16S4
assistant