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4-Aminobenzoic acid (also known as para-aminobenzoic acid or PABA because the number 4 carbon in the benzene ring is also known as the para position) is an organic compound with the formula H2NC6H4CO2H. PABA, a white-grey crystalline substance.
A 1908 (OTTO) 4-Aminobenzoic acid, 99% Cas 150-13-0 - used in the following Covalent modification of glassy carbon electrode.