Beschreibung:
<jats:p>Infrared spectroscopy was used to evaluate the effect of non‐iron porphyrins (protoporphyrin IX and haematoporphyrin) on haematin polymerisation to β‐haematin at acidic pH. Both molecules effectively inhibited the reaction, with haematoporphyrin 6 times as active as protoporphyrin IX. We postulated that the interaction between the π electron system of porphyrin rings leads to the formation of π–π adducts, which inhibit polymer elongation in the same way as antimalarial drugs (e.g., chloroquine); the presence of hydroxyl groups able to bind haem iron enhances activity.</jats:p>