3-Chloro-4-[N'-(2-ethoxycarbonyl-1-methylethylidene)hydrazino]benzenesulfonic acid C??? ??, ??, ??

3-Chloro-4-[N'-(2-ethoxycarbonyl-1-methylethylidene)hydrazino]benzenesulfonic acid ?? ?? ? ???

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3-Chloro-4-[N'-(2-ethoxycarbonyl-1-methylethylidene)hydrazino]benzenesulfonic acid ?? ??