Synthesis and coordination properties of superstructured iron-porphyrins
Superstructured iron (II)porphyrins have been designed to closely approach the properties of oxygen carrier hemoproteins and yield useful information concerning their biological structure and function. "Basket-handle" porphyrins and "hybrid" porphyrins allow one to modify the constraint exerted on a chelated "proximal" base as well as to alter the chemical and steric environment of the distal side of the heme which controls selectivity of 2 and CO binding. The presence of amide groups in the vicinity of the heme ring gives the possibility of forming a cavity to stabilize dioxygen or hydroxyl ion on iron (H) and carbon monoxide on iron (I).