4-Acetylphenoxyacetic acid is a phenoxyacetic acid derivative. It has been synthesized by employing para-acetyl phenol as starting reagent.4-Acetylphenoxyacetic acid is suitable as a test compound in the study of phenylacetic acid transport system (PATS) of Pseudomonas putida U by the aerobic catabolism of phenylacetic acid derivative used as the sole carbon source. 4-Acetylphenoxyacetic acid is a phenoxyacetic acid derivative. It has been synthesized by employing para-acetyl phenol as starting reagent.