Zur Chemie des Blutfarbstoffes. 6. Mitteilung. Über die Beziehungen zwischen Hämin, Hämochromogen und Porphyrin.

Abstract

The combination of FeCl3 with porphyrin to form hem-ins succeeds only in the presence of the reducing agent, glacial acetic acid. If butyric or valeric acid are used in place of acetic, the Fe combines only as FeCl2. Therefore hemin contains dibasic Fe; one NH group of the porphyrin being replaced by FeCl, the other NH group remaining unchanged. This corresponds with the findings that hemin forms a tri-Ca salt (Kuster); that it contains 3 active H atoms instead of 2; and that hemin-dimethylester gives off HC1 to form des-HCl-hemin-ester, the HC1 being split off from the FeCl and NH. Hemochromogen is derived from hemin by giving off Cl or OH, not by taking up H, for it is formed from Cl-hemin even in the absence of H or O, e.g., by treating with pyridin + Na.