4-Chlorophenylacetic acid (Standard) is the analytical standard of 4-Chlorophenylacetic acid. This product is intended for research and analytical applications. 4-Chlorophenylacetic acid is a halogenated phenylacetic acid derivative. 4-Chlorophenylacetic acid is a potent aromatase inhibitor and antagonizes estrogen signaling. 4-Chlorophenylacetic acid can provide carbon and energy for Pseudomonas sp. strain CBS3. 4-Chlorophenylacetic acid is effective against estrogen-induced mammary tumorigenesis[1][2].