15118-60-2

4-(4-Aminophenyl)butyric acid (4-APB) is an important organic compound derived from butyric acid, which is used as a synthetic intermediate for pharmaceuticals or the synthesis of various compounds. It is also used in drug mechanism studies and is thought to be an agonist for certain G-protein coupled receptors and may also interact with other proteins in the signal transduction pathway. In addition, 4-(4-aminophenyl)butyric acid has been found to inhibit monoamine oxidase, which plays a role in neurotransmitter catabolism.

4-(4-Aminophenyl)butyric Acid is a degradation product of Chlorambucil (C325050); an alkylating agent that is used as an chemotherapy drug in the treatment of chronic lymphocytic leukemia. Chlorambucil is also used to treat non-Hodgkin''s lymphoma (NHL) and Hodgkin''s disease.

reaction type: solution phase peptide synthesis

The general procedure for the synthesis of 4-(4-aminophenyl)butyric acid from 4-(4-acetamidophenyl)-4-oxobutanoic acid was as follows: 89 g of 3-(4-acetamidophenyl)propionic acid, 88 g of potassium hydroxide, 65 ml of 85% hydrazine hydrate and 450 ml of diethylene glycol were mixed and heated and refluxed for 1.5 hours. Subsequently, the reaction temperature was raised to 150°C to remove excess hydrazine hydrate and the reaction was maintained at this temperature for 4 hours. Upon completion of the reaction, it was cooled to room temperature, 400 g of water was added, and the pH was adjusted to 6 with 6N hydrochloric acid, and then adjusted to 5-6 with glacial acetic acid. at this point, the target product precipitated as crystals, and after filtration, washing and drying, 44 g of white or near-white crystals were obtained in 95% yield.

[1] Patent: CN104447376, 2016, B. Location in patent: Paragraph 0032-0033; 0043-0044
[2] European Journal of Medicinal Chemistry, 2018, vol. 146, p. 588 - 598