Wikipedia
Orthanilic acid
Orthanilic acid (2-aminobenzenesulfonate) is a biological acid with roles in benzoate degradation and microbial metabolism in diverse environments.
Orthanilic acid promotes reverse turn formation in peptides, inducing a folded conformation when incorporated into peptide sequences (Xaa-SAnt-Yaa), showing robust 11-membered-ring hydrogen-bonding.
Orthanilic acid is a structural component of some azo dyes which consequently have poor bacterial degradation.
Oorthanilic acids have also been found to affect cardiac tension.