Arias-Gómez A, Macías MA, Portilla J. Synthesis of structural analogues of Reversan by ester aminolysis: an access to pyrazolo[1,5-
a]pyrimidines from chalcones.
RSC Adv 2023;
13:16377-16386. [PMID:
37266500 PMCID:
PMC10230348 DOI:
10.1039/d3ra02553e]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 05/17/2023] [Indexed: 06/03/2023] Open
Abstract
Reversan, a multidrug resistance-associated protein (MRP1) inhibitor described more than a decade ago, is a commercial drug (CAS: 313397-13-6) that has a high price and is six to eight times more potent than known drug transporter inhibitors. However, to date, a complete route for synthesizing pyrazolo[1,5-a]pyrimidine-based Reversan is yet to be published. Herein, the silica gel-mediated synthesis of Reversan and a novel family of its structural analogues (amides) via the microwave-assisted amidation reaction of 3-carboethoxy-5,7-diphenylpyrazolo[1,5-a]pyrimidine (ester) with primary amines is reported. Moreover, a set of this ester-type precursor was obtained using the NaF/alumina-mediated reaction of 5-amino-3-carboethoxy-1H-pyrazole with chalcones, implying a final removal of H2 using Na2S2O8. Both esters and amides were obtained in high yields using heterogeneous catalyst and solvent-free, highly efficient, and scalable synthetic protocols.
Collapse