Sythetic and biosynthetic studies of porphyrins. Part 1. Synthesis of the ‘S-411’ porphyrin obtained from meconium

Abstract

S-411 porphyrin is shown to be 2-(2-carboxyvinyl)-1,3,5,8-tetramethylporphin-4,6,7-tripropionic acid by synthesis via the b-oxobilane and MacDonald routes. The isomeric 4-(2-carboxyvinyl)porphyrin was also prepared by the MacDonald route. In each case the acrylic acid side chain was introduced at the porphyrin stage. The two isomeric porphyrins were clearly distinguished from one another by m.p., n.m.r. spectra, and steady-state counter-current distribution. The role of the S-411 porphyrin in relation to porphyrin biosynthesis is discussed.