Abstract
Aspartic α- and β-monohydrazides and aspartic α, β- and glutamic α, γ-dihydrazides were prepared and their qualitative separation has been performed by means of paper ionophoresis and chromatography. During ionophoresis in acidic medium, the dihydrazide partially decomposed into the isomers of monohydrazides liberating hydrazine. The hydrazinolysis products of whale and beef insulins were analyzed by the aid of elution chromatography on a Dowex 50 column and it was observed that the C-terminal positions were occupied by each one mole of alanine and asparagine in both cases. Furthermore, the present experiments suggested that all of the non-terminal carboxyl groups of the hormone belonged to only glutamic acid residues. Complicated reaction of the acidic amino acids or their amides with hydrazine was discussed.
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