4,9-Dihydroxyphenazine-1,6-dicarboxylic acid dimethylester and the 'missing link' in phenazine biosynthesis

4,9-Dihydroxyphenazine-1,6-dicarboxylic acid dimethylester, the ester form of a proposed 'missing link' in the biosynthesis of phenazines, has been isolated from a strain of Pseudomonas cepacia.