A SIMPLE DETERMINATION OF VITAMIN A IN MARGARINE: II. ON THE REACTION BETWEEN YELLOW AB OR OB AND ALDEHYDES

In the simple assay method of vitamin A in margarine which has been devised by the authors, yellow AB and OB were found by condensing with acetaldehyde to form phenylazo-acetaldehyde-β naphthylimide or o-tolylazo-acetaldehyde-β-naphthylimide which can be removed easily by acetic acid. Various phenylazo-aldehyde-β-naphthylimides and o-tolylazo-aldehyde-β-naphthylimides were prepared from yellew AB or OB and their chemical properties were described.