Reactions of Hæmoglobin and its Derivatives with Phenyl Hydroxylamine and Nitrosobenzene

Abstract

ON addition of a small amount of phenyl hydroxylamine (C₆H₅.NHOH) to a fresh alkaline solution of hæmatin prepared from hæmin crystals, the colour of the solution turns rapidly from brown to bright red and its absorption band at about 630 mµ is replaced by two strong but somewhat diffuse bands at 562 mµ and 532 mµ. Two molecules of phenyl hydroxylamine per molecule of hæmatin are required for the complete formation of this new compound. Its instantaneous formation suggests in the first instance the view that in this reaction hæmatin combines directly with the phenyl hydroxylamine in the same way that it does with a variety of other nitrogenous substances. This view was not, however, supported by further experiments, which can be summarized as follows :