130. Reaction of 5,6,7,8-Tetrahydropterin with Iron(III) Acetylacetonate. Detection of Radical Cations by Electrospray Ionization Mass Spectrometry

Article abstract of DOI:10.1002/hlca.19950780710

The experimental conditions developed for the detection of rather stable radical cations in solution by electrospray-ionization mass spectrometry (ESI-MS) of a Fe(II) complex of 2-amino-5,6,7,8-tetrahydro-5-methylpteridin-4(3H)-one (1c) are used to observe the formation of the more unstable radical cations formed from 2-amino-5,6,7,8-tetrahydropteridin-4(3H)-one (1a) and tris(pentane-2,4-dionato)iron(III) (; 4) and to monitor their oxidation to the corresponding p-quinonoid dihydropterin complexes.These results contribute to the understanding of the important role played by 6β-5,6,7,8-tetrahydro-L-biopterin (1b; a homologue of 1a) together with iron as constituent of some cofactors.The complexes obtained from 1a and iron may be considered, e.g. as a model of the cofactor of the phenylalanine hydroxylase.Moreover, we describe an improved synthesis of 1c.