An efficient method for the conversion of 2-bromo-5-tosylpyrroles to the corresponding 5-tosylpyrrolinones as the D-ring of phycocyanobilin derivatives

Article abstract of DOI:10.1246/cl.2001.590

2-Bromo-5-tosylpyrroles were efficiently converted to the corresponding 5-tosylpyrrolinones as the D-ring of phycocyanobilin (PCB) derivatives by treating with DMSO and Zn in TFA in the presence of a catalytic amount of iodine. PCB derivatives modified at the D-ring were prepared in free acid forms employing the resulting 5-tosylpyrrolinones toward structure/function analysis of phytochrome.