ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Novel and facile process for the preparation of Brexpiprazole an antipsychotic drug

Deekonda Satheesh, Bhavanam Sekhara Reddy, Keloth Basavaiah, Vaddi Pandu Ranga Rao, Ramadas Chavakula, B. Sreenivasulu, and Anil Kumar Guduri

Chemical Research and Development Department, APL Research Centre-II, Aurobindo Pharma Limited, Telangana State, Sangareddy District, India

E-mail: satheesh.deekonda@gmail.com

Received: 21 November 2022  Accepted: 21 December 2023

Abstract:

A novel and industrially viable process was developed to synthesize Brexpiprazole an antipsychotic drug. This process involves using 1,4-butanediol as a key starting material, which is then diprotected and subsequently reacted with 7-hydroxy-2(1H)-quinolinone and piperazine-l-benzo[b]thien-4-y1 hydrochloride using potassium carbonate as a base, resulting in a novel intermediate, the spiro-tosyl salt, with a good yield and purity. Various conditions, solvents and bases were evaluated to optimize the coupling reaction of tosyl salt with 7-Hydroxy-2-(1H)-Quinolinone. Finally, we have chosen Sodium carbonate as a base and selected N,N-dimethylacetamide as a solvent. The reaction was carried at an elevated temperature, resulting in the production of Brexpiprazole with good yield and excellent purity. The product is fully characterized by using analytical methods like ¹H NMR, ¹³C NMR, HPLC and HRMS analysis.

Graphical abstract

Keywords: Brexpiprazole; 7-Hydroxycarbostyril; Benzothiophenepiperazine hydrochloride; Spiro-tosyl salt; Active pharmaceutical ingredient

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03289-y

Chemical Papers 78 (5) 3017–3022 (2024)