Compounds for Iron in Biological Systems

Model Compounds for Iron in Biological Systems.—There have been a number of publications concerned mainly with the nature of iron-sulphur-containing proteins, nitrogen fixation, and oxygen transport. Most of these are concerned with studies on cluster compounds of the type [Fe4S4(SR)4]2.  

van Tamelen, Abstract of 24th Congress of IUPAC, Hamburg, 1973, p. 152, 

Following previous work on the Raman spectra of rubredoxin and adrenodoxin, Scovell and Spiro have reported a detailed study of the vibrational spectrum of Fe2S2(CO)6 (syn- and anti-isomers), which they suggest may be used as a model compound.316 

Attempts to simulate oxygenation of haemoglobin have previously been thwarted by reaction (b) in the scheme  

Use of fatty acid monolayers as models for membrane catalysis has shown that the reactivity of iron(m) porphyrins in these surfactants is different from that in solution. A very ready formation of the p-oxo dimer was demonstrated and the suggested mechanism is  

It has been found that magnetic measurements, n.m.r., i.r., and electronic spectra 

MO calculations on FefPorjOj, FefPorjOjCNHj), FefPorXNHajj and Fe(Por)CO support an Fe -02 rather than an Fe -02 formulation. MO calculations have also been performed for Fe(Por)02(2-methylimidazole) and Fe(02)SMe systems. Oxygenation of cis-Fe(bt)2(NCS)2 (bt = 2,2 -bi-2-thiazoline) in non-aqueous solvents yields a product having properties consistent with a dinuclear structure. It 

299ii Tsuchida, K. Honda, and H. Sata, Inorg. Chem., 1976,15, 352. 

has been used to determine the conformation of substrate molecules bound to haemoproteins and a structure has been suggested for indolepropionic acid-horseradish peroxidase in which the indole ring is located 9—10 A above the haem iron atom.  

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