Phenylhydrazone

Hydrazones are a class of organic compounds with the structure R
1R
2C=NNH
2. They are related to ketones and aldehydes by the replacement of the oxygen with the NNH
2 functional group. They are formed usually by the action of hydrazine on ketones or aldehydes.

The formation of aromatic hydrazone derivatives is used to measure the concentration of low molecular weight aldehydes and ketones, e.g. in gas streams. For example, dinitrophenylhydrazine coated onto a silica sorbent is the basis of an adsorption cartridge. The hydrazones are then eluted and analyzed by HPLC using a UV detector.

The compound carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (abbreviated as FCCP) is used to uncouple ATP synthesis and reduction of oxygen in oxidative phosphorylation in molecular biology. Phenylhydrazine reacts with glucose to form an osazone.

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