4-Aminobenzoic acid (also known as para-aminobenzoic acid or PABA) is an organic compound with the formula H2NC6H4CO2H. PABA is a white crystalline substance that is only slightly soluble in water. It consists of a benzene ring substituted with an amino group and a carboxyl group.
Industrially, PABA is mainly prepared by two routes: reduction of 4-nitrobenzoic acid and the Hoffman degradation of the monoamide derived from terephthalic acid.
Food sources of PABA include liver, brewer's yeast (and unfiltered beer), kidney, molasses, and whole grains.
