Phenylhydrazine hydrochloride is used in the examination of tyrosine phosphorylation of Janus protein tyrosine kinase (JAKs) in the EPO-responsive normal erythroblastoid cells of anemic mice.

Application

 Phenyl-hydrazine is used to prepare indoles by the Fischer indole synthesis, which are intermediates in the synthesis of various dyes and pharmaceuticals. Phenylhydrazine is used to form phenylhydrazones of natural mixtures of simple sugars in order to render the differing sugars easily separable from each other.