A Biomimetic Synthesis of a Porphobilinogen Precursor Using a Mukaiyama Aldol Reaction

Four steps suffice! A protected porphobilinogen was obtained in 25 % yield in a straightforward synthesis starting from a derivative of 5-aminolevulinate. The key was the use of a cyanide derivative instead of the azide. The synthesis imitates the mechanism proposed by Shemin for the biosynthesis of porphobilinogen. Phth = phthaloyl.