
%0 Journal Article
%A Clezy, PS 
%A Fookes, CJR 
%T The chemistry of pyrrolic compounds. XLVII. The synthesis of a possible biogenetic precursor of haem <I>a</I> and its relationship to the prosthetic group ofmyeloperoxidase and to cryptoporphyrin <I>a</I>
%J Australian Journal of Chemistry
%D 1981/04/01
%V 34
%N 4
%P 871-883
%K 
%R https://doi.org/10.1071/CH9810871
%U https://www.publish.csiro.au/paper/CH9810871 
%X The synthesis of 18-demethyl-18-formylprotoporphyrin dimethyl ester is described and the role of this compound as an intermediate in the biosynthesis of haem a is considered. A possible relationship between a compound of this structure and the prosthetic group of myeloperoxidase is discussed. The cryptoporphyrin a fraction of ox heart extracts has been reexamined and shown to consist of a mixture of Spirographis porphyrin and its isomer which presumably arise from the in vitro oxidation of the vinyl groups in protoporphyrin. 
