Modified substrates for tetrapyrrole biosynthesis: analogues of porphobilinogen showing unusual inhibition of porphobilinogen deaminase

Abstract

Syntheses are described of two analogues of porphobilinogen (PBG), a fluoro derivative 10 and a phosphonate 13, which are the first known unnatural substrates of PBG deaminase; when they act as inhibitors of the reaction of PBG, these compounds produce unusual sigmoidal kinetics, explained by their involvement as poor substrates in the particular mechanism of this enzyme.