Substituted iron-chlorins and their complexes with globin spectral comparisons with myeloperoxidase

• 1.1. The spectra of the iron complexes of mesochlorin, deuterochlorin, monoacetyldeuterochlorin, phaeophorbides a and b, 2″-formylcholine e₆, alone, in combination with globin, and as pyridine ferrohaemochromes, have been studied.
• 2.2. The spectra of the model iron-chlorin-globin compounds have been compared with corresponding forms of myeloperoxidase as guides to the nature of the haematin prosthetic group of the enzyme. Previous suggestions that myeloperoxidase haematin has a chlorin-like conjugation are supported by the above spectral evidence which, nevertheless, confirms that some forms of myeloperoxidase exhibit atypical spectra.